7. preservation-brief-45-wood-porches

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45 PRESERVATION
BRIEFS
Preserving Historic Wood Porches
Aleca Sullivan and John Leeke
National Park Service
U.S. Department of the Interior
Few architectural features evoke more romantic notions
or do more to define a building 's historic character than
the American porch. The size, style, detailing, and
location of a porch can tell volumes about the age and
use of a building. Each component, from handrail or
baluster to column or post, enhances the architectural
character of the porch. Alter or remove the porch and
a historic building or streetscape can lose its visual
integrity and historic authenticity (Fig 1).
Functionally, a porch protects an entrance from the
weather. Yet open porches are constantly exposed
to sun, snow, rain, and foot traffic, and thus subject
to deterioration, perhaps more than other parts of a
building. Wood porches are particularly vulnerable.
Deferred maintenance and neglect account for the
decay and loss of countless numbers of historic porches
each year. Deterioration from moisture and resultant
wood rot, and damage caused by wood-eating insects
are common problems that, when left unaddressed
too long, can lead to the loss of significant historic
fabric. Inappropriate repairs or insensitive alterations,
such as the enclosure of a front porch, can be equally
destructive and negatively affect the porch's appearance.
All these things can alter a building's historic character.
To preserve the character of the porch, as well as the
historic building itself, it is essential to plan carefully
before undertaking any work on a historic porch.
This Preservation Brief provides guidance for the
everyday care of wood porches on older buildings.
It focuses primarily on the maintenance and repair
of wood porches, but acknowledges other, often
challenging, work as well. This publication provides
a brief history of the American porch and identifies
its basic structural and decorative elements.
It outlines how to assess the condition of
a wood porch, how much work may be
needed, and how to develop a specific scope
of work. Detailed guidance on each level of
work is provided, beginning with routine
maintenance, followed by general repairs for
various porch components, and concluding
with replacement of parts that are beyond
repair. Recommendations are provided for
work that may require professional assistance.
Although the Brief primarily addresses
residential buildings, much of the information
can be applied to wood porches on any
structure.
Evolution of the Porch
Figure1. Distinctive yet different,thesefront porchesare importantfeatures along
the street. The rhythm would be diminishedif thefront porchfrom one of the houses
was dramaticallyalteredor removed. Photo: A lecaSullivan.
In colonial America, buildings in the northern
colonies tended to echo British precedents
with small gable-roofed extensions to protect
main entrances . Whether open or enclosed,
these extensions were called porches (from
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Figure2. Porches not only help define the architecturalcharacterof
a building but alsoserve as living areas. They can be designedto
takeadvantageof surrounding views. CedarGrove,the homeof the
nineteenth-century landscapepainter ThomasCole, has an L-shaped
veranda on thefront and a two-storyporch011 the rear,providing an
enviableview of the CatskillMountains. Photo: Marilyn Kaplan.
Medieval English and the French word porche,which
stems from the Latin, porticus). Also known as porticos
when supported by columns, these covered entrances
were sometimes designed to respect classical order and
details, especially on more stylish buildings. Hooded
doors or small covered entryways flanked by benches,
often called stoops (from the Dutch stoep for step) that
served as short covered transitions to and from the
outdoors were common features, especially in New York
and the mid-Atlantic colonies.
During the late 1700s and early 1800s as longer shed-
roofed porches became more common, they were
typically called piazzas,as they were then called in
England. This term, still popular in some areas of North
America, is adapted from the Italian word for open
space or plaza. An alternate term for a long open porch,
veranda,reflects British colonial design influence from
the Indian sub-continent.
In French colonial areas, such as the Louisiana Territory,
houses were often built with broad roofs extending well
beyond the exterior walls to form surrounding porches,
known as galleries. Porches were also important
features of Spanish colonial buildings. In California,
for example, many adobe ranches featured a portal
with the roof supported by wooden posts. African
and Caribbean influences can also be found in North
American porch traditions.
By the late eighteenth and early nineteenth centuries,
porches became more common in larger, wealthier areas
such as Philadelphia, Boston and Charleston. In both
the North and the South, formal colonnades with tall
columns dressed in classical orders were sometimes
added to help dignify public buildings, hotels, and
mansions. This trend continued through the 1830s
and 1840s, as the Greek Revival became the dominant
architectural style in many areas of North America .
The social role of porches as a transition space between
indoors and outdoors and as a link between private and
public realms evolved during the 1800s. By offering
grand entrances and sheltered landings with views of
the surroundings, prominent porches became expected
features of inns, hotels and resort spas, where they could
serve as promenades, social gathering spots, and refuges
for more private retreats. Porches were also added to
private homes to serve many of these same functions
(Fig 2). As the country began to thrive and expand,
porches became more than just covered enh"ances or
ceremonial features; they became an integral part of
domestic social life
Some of the most significant factors that aided
this shift were America's industrialization and
later suburbanization. As improvements to mass
production methods helped spur industrial growth,
many Americans had more money to spend and more
leisure time. Meanwhile a growing middle class was
moving to new suburban neighborhoods. Inspired by
the pattern books of Andrew Downing and George
Woodward and the published designs of such architects
as Alexander Jackson Davis and Calvert Vaux, the
homes of these mid-1800s suburban neighborhoods
were typically ornamented by elaborate porches dressed
with fancy millwork. By this time, millwork catalogues
and builders' pattern books offered a wide variety of
designs for porch parts. With mass production, these
fancy brackets and other ornamentation became less
expensive, making it easier and more affordable to
construct decorative porches (Fig 3). With mechanized
wood turning lathes, the cost of posts, balusters and
decorative spindle work also decreased to a level
affordable by many. Adding a porch with wood
ornamentation could enhance even the smallest
and simplest of houses. Even older homes could be
modernized with a fancy porch addition, stylized to
the latest fashion trends. Such changes culminated in
the large, highly decorated wrap-around porches of the
Queen Anne style.
The second half of the nineteenth century was the golden
era of porches. The social role of the porch increased as
it evolved into an outdoor parlor, a true extension of the
house into the landscape. Often partially screened by
shrubs, porches could provide occupants with discreet
opportunities for social contacts that might otherwise be
difficult to achieve in an age obsessed with manners and
proprieties. For many, sitting on the porch became an
important part of their daily routine. Perhaps President
Rutherford B. Hayes best summed up the love that
Victorian-era Americans felt towards their porches when
he recorded in his journal in 1873: "The best part of the
present house is the veranda. But I would enlarge it. I
want a veranda with a house attached."
By the early twentieth century, the hygiene movement,
which stressed that access to fresh air could help prevent
or remedy such diseases as tuberculosis, contributed to
the development and proliferation of the sleeping porch.

These porches were usually located on the second
floor next to bedrooms. This era also saw the rise in
use of insect screening on porches to guard against the
discomfort of mosquitoes and the diseases they spread,
such as yellow fever and malaria.
While innovations fostered the proliferation of porches
in the nineteenth century, new inventions helped lead
to its decline in the twentieth. As the automobile
boom of the early twentieth century made it easier for
people to get out of the house for entertainment and
relaxation, porches began to lose popularity, especially
as architectural styles and social attitudes changed . With
the telephone, neighbors and friends could chat without
personally meeting. And housing styles popularized
in the construction boom after World War II often
omitted front porches all together as backyard patios
became the focus of private outdoor activities. Finally
in the mid-twentieth century the broad availability of
air conditioning and television enticed many people to
stay inside at night and brought the golden era of the
American porch to an end.
Figure3. Throughoutthe late nineteenthand early twentieth
centuries,millwork cataloguesoffereda wide variety of designsfor
porchparts, including columns, newels, balusters,spindles and
brackets. As extolled in the CedarRapid Sash & Door Company's
Standards Design Book, stockparts made embellishments to porches
affordablebothfor new construction and "updating" existing homes.
Courtesyof CharlesFisher.
Understanding the History and Significance
of a Porch
In preserving historic buildings, it is important to
understand the history and evolution of a particular
structure and what features contribute to its historic
character. This is especially applicable when working
with historic porches since they usually are prominent
features, significant to the character of a building.
Answers to the following questions will help establish
the significance of a porch.
What has the porch looked like in the past?
Early photographs, insurance maps, or tax records can
provide useful information. These may be found at city
or county offices, historical societies, libraries or even
from former owners or neighbors. Such documents may
indicate the footprint of the building or show long-lost
details of the building's appearance. Physical evidence
of historic porch footings may exist. Paint shadows of
a former roofline or moldings can provide clues about
details now missing . Old porch parts may have been
"stored " under the deck during past repairs.
What, if any, changes have taken place to the historic
porch over the years? On many porches elements such
as columns, balusters, and finish details correspond with
the design and detailing on the rest of the house. With
other porches, the style of these features may differ from
the rest of the building, but may reflect an important
chapter in its history. Sometimes, parts of porches
may have been lost due to neglect or remodeling.
Questions about what historic fabric remains, what has
been altered over time, and whether earlier changes
are now an integral part of the historic character
should be resolved before planning major porch work.
Determining the historical evolution of the house may
require both physical and archival research and in some
cases the professional eye of an architectural historian.
What are the character defining features of the porch?
The open qualities are one of the key features of most
historic porches. Overall size, shape and design are
obviously important components as well. There are
numerous other contributing features which may exist,
including the shape of the porch roof, the way a large
porch is divided into distinct bays as with columns, the
nature of the supporting foundation, the style and size
of columns and balustrade, and whether the porch is
raised or largely at grade. The simplicity of a porch or
its richness in detail will also help define it. Materials
are usually important as well, not just the wood features,
but also whether other materials exist such as masonry
columns and steps (Fig 4).
How does the porch contribute to the building's
overall appearance? The size and location of a porch
and how much of the historic features survive will help
define its significance. A highly ornate porch across
much of the front facade may be the most distinctive
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Drawing courtesy of ThomsonEducation Direct.
k
4
a - Pier, penetrates ground, supports floor structural
system and columns
b - Fascia covering floor framing
c - Floor (or deck)
d - Bed Molding covering joint between fascia and floor
e - Column supporting entablature above
Entablature (f, g, h)
f - Architrave of entablature
g - Frieze of entablature
h - Cornice of entablature
Roof Railing (i, j, k, 1)
i - Newel (or Pedestal ) of roof railing
j - Balusters of balustrade
k - Top rail of balustrade
1- Bottom rail of balu strade
Balustrade around floor (m, n, o)
m - Top rail of balustrade
n - Balusters of balustrade
o - Bottom rail of balustrade
Structural system of deck (p, q, r)
p - Girder rests on piers and ledgers , support joists
q - Ledger fastened to house sill, supports girder
r - Joist fastened to girder, supports floor
Roof Structural System (s, t, u)
s - Beams inside the entablature span from column to
column, support plate
t - Plate of the entablature rests on beams, supports
roof rafters and ceiling beams
u - Rafter of the roof structural system
The Anatomy of a Porch

feature of the entire house, while a small simple
porch on an otherwise plain cottage may be equally
significant. The architectural style of a porch may
relate to the building and may help define its character.
Sometimes a later style porch may have been added to a
building or may have replaced an earlier porch. In such
cases, the later porch may have acquired importance in
its own right. On the other hand, a later porch may be
of such poor quality that it detracts from the building's
historic character. Because porches are so diverse in
terms of style, size, shape and detail, their significance
should be assessed on a case-by-case basis with an
understanding of the overall importance and evolution
of the building.
Assessing the Condition
Before undertaking most repairs, it is important to
assess the condition of the porch. The assessment
is greatly facilitated if the porch has been regularly
maintained and a record of past work is available.
In most cases, however, a condition survey must
rely almost exclusively on the physical examination
of the porch, documenting the findings with notes,
photographs or sketches.
Many older porches were constructed using good
construction practices and materials. As a result,
porches that are over 100 years old are not uncommon.
Most porch deterioration can be attributed to the lack
of proper maintenance. Important questions to address
in assessing the condition of the porch include the
following:
How is the porch constructed? A porch is rarely an
independent, unattached structure. It may, however,
have its own foundation, attached to the house only
along the deck and the roof. Alternatively, it may be
an included or engaged porch that is integrated with
the actual structure of the house. The relationship
between the porch and the house is important. If
the outer support posts are decayed or if foundation
piers are sinking, the roof structure may be pulling
away from the house. Many porch decks are fastened
to the main building on a ledger, a horizontal board
along the house's foundation. A decaying ledger may
compromise the structural integrity of the porch and
can represent a major safety issue.
Are the foundation and structural members of the
deck sound and providing adequate support for
the deck, posts and roof above? The porch structure
needs to be sound at every level. Therefore, a visual
inspection of the underside of the porch is necessary
to determine its condition. Major cracks in structural
members, failed joints, significant wood rot, or evidence
of widespread insect infestations (termites, carpenter
ants or powder post beetles, for example) are usually
signs of serious structural damage. Such conditions
may require consultation with a professional architect,
Figure4. Celebratingthe 4th o!July in 1912, this gatheringof
family andfriends reflectsthe popularityof the porchas a social
gatheringplace. While not overly ornate,eachdetailof the porch
from the roofbalustradeto the turned columns to the simple lattice
workfacing the deckcontributesto its character,creatingin effect
the dominant architecturalfeature of the building. Photo:© Utah
State HistoricalSociety
engineer or building contractor familiar with old
buildings. For an adequate assessment, it may be
necessary to remove facing boards to check for potential
decay in the structural sill behind (Fig 5).
What is the condition of the porch? Porch foundations
may be a continuous wall of masonry, a series of
masonry or wood piers or metal pipes, or a combination
of these. Missing sections of the foundation, crumbling
masonry mortar joints, or areas where the sill or
joists no longer fully rests on the foundation may
represent serious deficiencies. What appear to be deep
foundation footings may only be stones or cement
blocks sitting on top of the ground. The footings must
be stable enough to adequately support the porch
in its current or intended use. The smell of mold or
appearance of fungal growth on wood beneath the
porch is an indication of deficient air circulation and
that conditions exist for wood decay. Recent changes
that can contribute to deterioration should be identified
for correction, such as a clothes dryer vent dumping
warm moist air underneath the deck. The enclosure of
original air vents in crawl spaces or the boarding up of
latticework between piers are other changes that will
usually promote an unwanted moist environment.
Are the porch posts providing adequate support?
Posts, pillars or columns usually help support the porch
roof or an upper deck. Establishing what the posts
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Figure5. Even historicporchesthat appearto be in total disrepairmay be repairable.While the roofneededreplacement,much of this porchwas
repaired,including suchfeatures as the decorativecolumns,ornamentalbrackets,and balustrade. Photos:John Leeke.
are made of and how they are constructed will aid in
understanding how they function and may deteriorate
over time (Fig.6). Although the posts on a wood porch
are commonly made of wood, they may be of masonry
or metal or a combination of materials. Large round
columns usually are made of wood staves similar to the
way barrels are constructed; smaller diameter columns
may be solid. A sag in the deck below or a faltering
foundation can impact the supporting role of a column
or post above. Wood columns and posts are prone to
water seeping into open joints, particularly in the base
and the lower end of the shaft. It is not uncommon
to find that older columns have had patches and
replacement bases.
Is the roofing and drainage system keeping the water
away from the porch? Porches were designed to shed
water. This means water will move away both from
the building and the porch and not pond and saturate
the wood. Continuously high moisture levels promote
fungal growth that eventually causes wood to decay.
Peeling paint on ceiling boards in a specific location
is a sign of a possible roof leak. Clogged or missing
downspouts and gutters can cause erosion at the
foundation and can contribute to reverse-grade draining
that is directing water under the porch instead of into
the yard. Inadequately sloped porch floors can result
in improper drainage and promote deterioration as
exhibited, for example, by cupping floorboards.
What is the flooring condition? The porch component
most subject to decay is the flooring. Often decay
starts at the exposed ends of the boards or where
cracks, checks or open joints have occurred and are
exposed to the weather. Flooring should be checked
frequently for peeling paint, rotted wood, and for loose,
cupping or splintery boards. Where water is ponding,
there is insufficient slope away from the building, a
condition that should be corrected. Floor deterioration
can also start in unlikely places such as the result of
frequent hose washing to remove dirt or the placement
of plant stands directly on the floor without proper
moisture barriers. Firewood stored on a porch may
trap moisture on the floor and harbor active insect
infestation that can be ruinous to a wood porch. Thick
floor mats and carpeting also may trap moisture,
leading to premature decay.
Is there evidence of general wood decay?
Wood deterioration may take different forms such
as fungal decay, insect infestation or even sunlight
degradation of exposed unfinished wood. Decay may
be present where two wood surfaces meet and are not
adequately protected from water, such as along open
joints or behind moldings. Dark streaks, discoloration,
and widespread peeling paint on a finished ceiling
suggest excessive moisture or water leakage. It may be
necessary to remove several finished boards to properly
identify the cause of the problem and to insure damage
has not extended to structural members behind. Trails of
carpenter ants are another sign of potential decay since
they will infest moist decaying wood. Where inadequate
painting has left wood exposed for a long time, damage
to the wood surface from light itself will occur, typically
indicated by wood discoloration. Without sanding or
scraping back to a sound wood surface, repainting will
result in premature failure of the paint film.
Figure6. A traditionalway to extend the life of porchposts was to
placeposts on metalfeet, therebyprovidinga separationbetweenthe
woodpost and wood deck. This helpedto prevent the woodpostfrom
rotting at the base.Early postfeet weresimple iron barsbent unto a
stirrup shape. By the late nineteenth century manufacturedcast-iron
feet were common,consistingof a pair of disks separatedby a short
pipe. Postfeet arestill availabletoday. Courtesyof Old-House
Journal/BrianMcNeil.

Are there open cracks or joints in the woodwork?
Tightly sealed connections keep water out. Where
individual boards come together, cracks in woodwork
and joints can eventually become a major problem
(Fig.7). Cracks are primarily caused by movement and
water penetration. Movement of structural members
beneath the finished woodwork can shift the position
of individual boards and trim, breaking open the
thin coating of paint over joints. This condition is
common on porches with shallow foundations that are
subject either to annual winter frost heaving or where
soil conditions undergo major seasonal changes in
moisture content. Changes in the moisture content of
the wood itself due to repeated wetting and drying or
changes in seasonal humidity can also cause noticeable
expansion and shrinkage across the width of a board.
This provides opportunities for water to penetrate
unprotected areas.
Does peeling paint indicate deeper problems?
An unbroken layer of paint covering all wood surfaces is
the first line of defense against moisture causing decay.
Over time, even hairline paint cracks can allow water
to penetrate, causing paint to peel down to bare wood.
Such peeling occurs near breaks in the film, at opened
joints, or where the paint has been scratched or scraped.
Peeling can also occur over large areas where there is
high moisture and insufficient ventilation. Areas of
particular concern include the crawl space beneath the
porch deck, inside columns that lack ventilation, and
in a roof structure that has a finished ceiling and lacks
ventilation. If heavy paint build-up exists on columns,
floors and trim, moisture can be trapped within the
wood, resulting in the loss of paint adhesions and
eventual wood decay.
Are trees, shrubbery and flowerbeds threatening the
porch? Shade trees can make the porch a cool oasis,
but the branches of a nearby tree rubbing on the roof,
gutters or wood trim often will cause damage. Tree roots
may destabilize porch foundations or supports. Bushes
growing against the porch and not trimmed back on a
regular basis may block wood porch components from
drying breezes, thereby letting moisture build up in the
woodwork. Flowerbeds and mulch around the porch
that are not properly sloped downward in a grade away
from the house will promote moisture problems.
Defining the Scope of Work
Once the historical and physical assessments are
complete, it is important to define the scope of work.
How much and what kind of work will need to be
done to make the porch structurally sound while
preserving its historic character, or to recover its historic
appearance if portions are extensively deteriorated,
altered or missing? Any part of the porch that defines
its historic character should be repaired or replaced
to match. Since the porch may display varied levels
of deterioration, the spectrum of work in one project
Figure7. Commonproblemswith porchesthat can contributeto
seriouswood decayinclude cracksin woodworkand joints that have
openedup. Both providean easypathfor water seepage. Trapped
moisturecanfoster peelingpaint, wooddecayand insect infestation.
Openjoints and cracksshould be checkedfor evidenceof moreserious
decayand markedfor caulkingor repair. Photo:John Leeke.
can include maintenance, repair, and replacement.
When laying out the scope of work for the project, each
individual component and decorative element of the
porch should be identified, and linked with the work
needed for that item.
Undertaking the Work
The highlighted work approaches in this section are
based on The Secretaryof the Interior'sStandardsfor the
Treatmentof Historic Propertiesand the Accompanying
Guidelinesfor RehabilitatingHistoricBuildings. The
Standardsand Guidelinesprovide a sound philosophical
and practical framework for achieving the highest
retention of historic materials and character possible.
Thus, the familiar hierarchy is applied: maintain, repair,
and then replace only if necessary. Contemporary
alterations are discussed in a separate section.
Preservation and Maintenance
There are a variety of tasks that can be done on a regular
basis to extend the life of a porch. In addition, a visual
inspection of the porch should be made every spring
and fall to determine if more in-depth repairs
are necessary. Fortunately, ongoing maintenance
significantly reduces both the need and cost for later
repair work and represents good preservation practice.
When properly maintained, a well-constructed porch
can last for decades.
Routine Cleaning and Other Surface Work
Since many porches are essentially another living space,
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extending housekeeping to this space makes practical
sense. Regular maintenance includes sweeping the
wood porch decking, and, if needed, an occasional
damp mopping. Removing dirt and leaves by sweeping
is preferable to frequent hosing off the deck with
water. The latter can saturate the woodwork , thereby
promoting decay. Frequent sweeping will reduce the
accumulation of abrasive materials, such as dirt and
sand. While visually pleasing to some, vines and plants
should be kept trimmed away and not be trained to
grow onto or allowed to grow beneath porches. Plants
and vines unfortunately reduce ventilation, promote
a moist environment for insects and decay, accelerate
open wood joints and impede cyclical maintenance . As
an alternative, traditional freestanding trellises can be
used to support plant growth away from the porch.
There are certain precautions that are recommended
for wood floors. Rubber mats, rugs or indoor/outdoor
carpeting can trap moisture and condensation on their
underneath side and should not be used on a wooden
porch floor. Keeping flower pots up off the wooden
deck will help prevent moisture buildup and decayed
spots - wood, clay or metal "trivets" that hold the
pots an inch or more off the wooden deck are helpful,
but the pots should be moved to different locations
periodically . In colder climates, light snow can be swept
off the porch. Snow shovels with a hard rubber leading
edge or plastic shovels cause less damage to wood than
metal, while paint in good condition helps ice to release
more easily. Sand or clean kitty litter can be sprinkled
on ice to prevent slipping; however, they should be later
swept off the porch, as they are abrasive . Salt (sodium
Figure 8. Decaycan start when wood is left exposed to the weather
or where joints open up. An inexpensive way to extend the life of the
existing porchpaint without jeopardizing the historicmaterial is spot
paint and caulk where neededevery year or two. This cost-effective
procedure is particularlyeffective in maintaining woodporches where
the exposure to weatheringis high. Photo: John Leeke.
chloride) is not recommended for ice removal on older
porches as it can promote corrosion and failure of nails
and other fasteners. Magnesium chloride is an alternate
de-icing salt that is less corrosive and less damaging to
masonry and plants. If any de-icing salt is used, be sure
to scrub and rinse off the porch deck in the spring. Boot
scrapers and brush-mats at the bottom of the stairs are
recommended for muddy areas.
Painting
Spot painting and resealing of open joints should be
undertaken at least every other year (Fig. 8). Heavily
used stair treads may require more frequent paint
touchup . When peeling paint or bare wood is evident,
inspect to ensure it is not signaling deeper problems,
such as decay. With sound wood, scrape off the loose
paint, sand, prime, and repaint the area. Where lead
paint is present, appropriate lead hazard precautions
and procedures apply. Only top-quality exterior primers
and paints are recommended, selecting for the deck and
stairs specially formulated paints. Where wood porch
steps are exposed to moisture, grit added to the wet
paint during application will help improve safety.
Repair
Many repairs may be successfully undertaken
by property owners, while major projects often
require the special knowledge and equipment of an
experienced contractor. Repairs generally include
patching and reinforcement of historic materials. The
roof and foundation are particularly important to the
preservation and the structure of a historic porch yet
they often receive much less attention than ornamental
features. Their neglect will usually lead to more costly
work. Repairs to features such as a balustrade or
flooring can encompass limited replacement in kind
when the porch part is severely deteriorated or when
a part of a repeated feature is missing altogether. Some
common porch repairs are discussed in this section.
Filling Open Cracks or Joints
To seal open cracks or joints, start by scraping off
the paint back a few inches from the opening and
removing old caulk to expose bare wood. The opening
should be examined for any signs of wood decay,
and to determine if the joint is loose due to a loss of
connection, such as rusted nails. After correcting any
problems, apply a water-repellant wood preservative
that can be painted . Such preservatives are either an
oil-based or waterborne solution of oils or waxes with
mildewcide, fungicide and pesticide added. Then
apply a high quality exterior wood primer to the wood
surfaces where a sealant or caulk is to be used. Most
open cracks or joints then can be filled with a sealant
or caulk, while larger ones may need the addition of a
backer rod. In some cases, small metal flashing over the
crack or open joint may be more effective and longer
lasting but , when used, care should be taken with
proper installation. The final step is painting.

Patching with a Dutchman Repair
This traditional technique is often
used to repair localized cases
of decayed wood and, when
undertaken with skill and care, will
serve as a permanent repair (Fig. 9).
If the damaged area has a structural
function, temporary bracing or other
support will be necessary. Otherwise
the first step after removing any
paint around the damaged area is
to chisel or mechanically remove
the decayed wood. It is best to
use the same type of wood being
replaced and the new or recycled
wood should be seasoned to avoid
shrinkage. The repair procedure
involves cutting a piece of wood,
called a dutchman, slightly larger
than the area of damage that has
been cut out. The dutchrnan then
is laid over the damaged area and
an outline scribed into the original
wood surface below. Next, a chisel
or router is used to follow the
scribed line to form an opening in
the existing wood for the new piece.
Figure 9. The ends of porch roofrafters are often susceptibleto moisturedecay. When concealed
by a soffit or ceiling, rafters can be repaired by adding new sister boards. Whereroofrafterends
areexposed, splicing new wood onto the old (dutchmanrepair)and use of epoxy consolidantsand
fillers both preserve sound historicfabric while retaining the historicappearance.
Photo: Paul Marlowe, Marlowe Restorations.
As a preventive measure, an appropriate fungicide
should be applied to the surrounding old wood and
allowed to dry. The dutchrnan is then glued into place
with waterproof adhesive, such as an epoxy formulated
for wood . The repair is finished by trimming or sanding
the surface of the new wood down flush with the
surrounding existing surfaces, priming and painting.
Patching with Epoxy or Wood Fillers
There are a variety of commercial wood fillers . Cellulose
based fillers consist of wood fiber and a binder and have
been available in stores for many years. Only those
suitable for exterior applications should be used and
they will require a protective finish. Epoxies are a more
contemporary product, commonly used by experienced
contractors and woodworkers . Epoxies are petroleum-
based resins created by mixing two components in
accurate proportions that result in a chemical reaction .
The result is durable, moisture-resistant consolidants
and fillers that bonds tenaciously with wood, and can
be sawn, nailed or sanded. Epoxies are for use only
in areas that will be painted, as they do not take stain
and deteriorate under sunlight. Since epoxies are more
difficult to work with than other wood fillers, experience
working with epoxies is needed for successful repairs.
Repairing Railings and Balustrades
Balustrades and railings are not only practical and safety
features, they typically are highly visible decorative
elements . Unfortunately, balustrades and balusters are
frequently altered, covered, removed or completely
replaced even though in most cases they can be repaired
in a cost-effective manner. To preserve historic fabric,
the repair of old balustrades and railings is always the
preferred approach. A broken baluster usually is one
need of repair, not replacement.
in
Loose railings and balustrades present unsafe
conditions and need to be repaired as soon as possible.
Start by examining the points of attachment to
determine exactly why the railing or balustrade is loose.
Common reasons include rusted fasteners, decayed
wood, or physical stress that has broken the fasteners
or split the wood. Paint and decayed wood must be
removed . Where fasteners are broken yet the wood is
sound, the balustrade can be re-fastened using hot-
dipped galvanized or stainless steel nails or screws,
setting the heads of the fasteners below the surface of
the wood and using a wood filler to cover and seal.
Next repair deteriorated wood by using a dutchrnan
or wood-epoxy repair . The repaired joints then can be
sealed and painted.
Replacing Missing Balusters
The balusters help comprise a wood balustrade and
come in three general styles: simple rectangular shape;
flat, pattern-sawn (usually a board with some decorative
edge or cutout); and turned. It may be necessary to
replace certain balusters that are beyond repair or
missing altogether. Some are easy to replace with new
matching balusters while others can be more challenging
in terms of both design and costs. Finding or affording
replacement balusters may take time since they should
match the historic baluster as closely as possible. In
the meantime, unsafe balustrades can be temporarily
stabilized, introducing temporary new material that
soon will be replaced.
9

10
In replacing individual balusters, simple, rectangular
balusters should not be replaced with pattern-sawn
or turned ones unless physical or pictorial evidence
survives which indicate they previously existed
historically on that particular porch. Such an alteration
can change the historic appearance of the porch or be
incompatible with the character of the building.
Determine the size and shape of the missing balusters
either by examining adjacent ones or temporarily
removing an existing baluster as a sample. Heavy
paint buildup should be removed so that the original
dimension can be established. Scrape and clean the joint
locations and make repairs to any deteriorated areas.
A new baluster is then fabricated to match the original
in design and material, either on site or by taking a
drawing or sample to a local woodworking shop. The
new baluster should be made one-half inch longer than
needed on both ends. Measurements are taken from the
bottom surface of the top rail to top surface of the
bottom rail. Joints on the new baluster can be laid
out with a pencil, using a sliding bevel to transfer any
angles, and the new baluster trimmed to fit with a
handsaw . After test fitting, the ends and any exposed
end-grain of the baluster need to be sealed with a
high-grade primer or epoxy. Next, apply a paintable
water-repellant coating to all exposed wood surfaces,
and apply a primer. The baluster can then be fastened in
place with hot-dipped galvanized or stainless steel nails,
and the nails set. Finally, seal joints and fastener holes
and paint the baluster.
Repairing Column Plinths and Bases
Columns not only enrich the historic character of the
porch, they provide support for the roof structure above.
Because of their detail and complex construction they
can be costly to repair or replace, making maintenance
and minor repairs important. Column plinths and bases
tend to deteriorate because of their exposed location
on the outer edge of a porch (Fig. 10). Leaking gutters
can result in water draining into the entablature and
down into hollow columns, while clogged or capped
gutters can allow water to pour down and splash
back onto the column bases. Open joints and limited
wood decay can be repaired using methods previously
discussed . Column repairs usually are undertaken by
an experienced carpenter, since it may involve structural
support of the roof above .
Repairing Floorboards and Ceiling Boards
Floors should slope down toward the outer porch edge
for proper drainage. If drainage is inadequate, moisture
buildup will cause deterioration of the floorboards.
Flooring can also deteriorate due to movement in the
supporting structure below . If a floorboard is soft or
broken, the extent of decayed or split wood can be
determined by probing gently with an awl. The existing
floorboard can then be removed, cutting the length if
needed so that the end will center on the next nearest
joist or girder. Once the board has been removed,
the structural framing beneath should be examined
for deterioration and to ensure it is sound. A new
floorboard is then cut to length, and the outer edge
shaped to match the adjacent boards. After priming the
replacement board, nail it in place and repaint.
If a section of the ceiling is deteriorating, it is likely
that there is a roof or gutter problem . To determine the
cause of deterioration, inspect the ceiling, gutters and
roof, including the internal roof structure. After making
necessary repairs, the ceiling boards can be repaired in
much the same manner as a deteriorated floorboard.
Repairing the Porch Roof and Gutters
With roof leaks, the entire porch is at risk. Leaks can
promote decay in roof rafters, ceiling joists, and columns
as well as in areas more easily to detect such as the
ceiling and fascia. Inspect the roof covering, gutters and
flashing for deterioration and improper performance.
They can then be repaired or replaced, as needed, to
keep water out of the structure. Avoid having the
gutters and downspouts on the main roof drain onto a
porch roof.
Repairing the Foundation
Unstable foundation supports can cause serious damage
Figure 10. This nineteenthcentury porchcolumn is made of woodstaves, similar to the way a woodbarrel is put together. After replacingthe torus
and making dutchman repairsto the apophyge along the base, the column and pedestal are ready to be reinstalledon the porch. Photos: NPS files.

to a historic porch. There are numerous causes and
solutions. If the posts supporting the porch deck rest on
stones or brick set directly on the ground, there can be
seasonal shifts due to the changing moisture content of
the soil or freeze/thaw conditions that will require regular
attention. Under certain conditions, it may be advisable
to extend footings for the posts below the frost line.
Where moisture problems exist, improved drainage may
be necessary. It is not uncommon to find that masonry
joints in the foundation wall or piers have deteriorated
as a result of rising damp, where moisture from the soil
percolates up through mortar joints. This condition may
lead to the eventual breakdown of the mortar and even
old brick and soft stone. In such cases, it will be necessary
to replace the areas of damaged masonry and repoint the
mortar joints.
With wooden posts, insect damage or rot may necessitate
corrective measures to strengthen the foundation.
Techniques can include one or more of the following:
epoxy consolidation; dutchman repair; or the addition of
supplemental supports to the foundation posts and joists.
In some cases damage may be extensive enough that the
only real solution is rebuilding the foundation.
Repairing a Porch Apron
The apron, skirt, or latticework is a highly visible and
functional porch feature. An apron keeps animals out
from under the porch, while at the same time allowing
air to circulate, preventing unwanted moisture buildup.
Aprons typically are made up of a wood frame ,
surrounding either a simple lattice or a repetitive pattern
of decorative sawn boards. Because the frame is so close
to the ground, decay is common. Other causes of decay
include plantings around the house that are growing too
close to the latticework and improper water drainage. An
apron may require partial or complete disassembly for
proper repair. One or more of the apron frames should
either be hinged or secured with turn buttons for easy
access to under a porch for inspection and maintenance.
Replacement
When individual porch parts are deteriorated beyond
the point of repair or missing altogether, replacement
is necessary. To retain the historic character of the
porch , the replacement parts should match the historic
component as closely as possible in material, design,
color, texture, and other qualities . To achieve this,
existing evidence of the historic design, such as a baluster
or column detail, or a tongue and groove floor design,
should serve as a pattern for the replacement part . When
replacing an element, it may provide a good opportunity
to upgrade the wood to another species that is more
decay resistant, or to one with a vertical grain that is
more resistant to cupping or splintering . In limited
cases, it may be appropriate to use a substitute material
for the replacement material as long as it conveys a
close visual match . Before replacing a deteriorated
historic porch component, it is important to understand
how it was constructed and installed, and what lead
to its deterioration. If the replacement part does not
sufficiently match the historic part, the character of the
porch may be diminished, or even lost. If the cause of
material failure is not addressed, the replacement will
also fail.
Replacing Porch Floorboards
If a large section of the porch floorboards is deteriorated,
the framing beneath may also be damaged and should
be assessed. Replacing floorboards can often expand
into repairing the structural sills, girders, and joists
beneath. Complete floor replacement will likely require
the removal of floorboards that are under structural posts
or columns. This may necessitate the careful stabilizing
in place or the removal of the posts or columns and the
installation of temporary support for the roof structure.
If the floor failure was caused by inferior wood, the wood
quality can be improved at this time. However, the new
wood flooring should match the existing in thickness,
width, shape and texture. The slope of the floor should
be maintained, or a slope may need to be created if none
exists. A slope of ¼ inch per foot or greater, away from
the house, is needed for adequate drainage. Boards are
usually laid in the direction of the slope, sloping down to
the outer edge of the floor.
Replacing Steps
Porch stairs receive heavy usage and are close to the
ground, making them predictable candidates for
deterioration. Stairs should be repaired or, if necessary,
replaced by an experienced carpenter who understands
the safety codes and is experienced in fabricating custom
stair parts to match original detailing without depending
only on store-bought parts.
Replacing Column Plinths and Bases,
or Entire Columns
When plinths and bases are deteriorated beyond repair,
they can be replaced without replacing the column
shaft, which may still be in good condition or require
only minor repairs at the bottom. Such replacement
will involve temporary shoring for the roof. One-story
columns and shafts are often more easily removed
during this work, while taller columns are sometimes
supported in place. If only a few plinths or bases are
deteriorated, it is often economical to have new ones
made of wood to match. If numerous plinths and bases
are deteriorated, replacing with bases made of rot-
resistant materials can make economic sense; however,
care must be taken to ensure that all the visual qualities
including design, size, shape, color and texture of the
historic part are matched (Fig. 11).
Entire columns may need to be replaced, but an owner
should first consider all repair alternatives. Some
contractors routinely recommend complete replacement
of one or all columns due to the challenge of a clean
repair (particularly with stave-built columns), or because
they see the potential for more profit in complete
replacement. If a contractor recommends complete
11

12
Figure11. The lowershaft of the porchcolumns had decayedas
water wicked up through the end grain (top). The column shafts were
repairedin placeby cutting out the deterioratedwood and making
repairsusing epoxy consolidantsandfillers. (bottom). The column
bases were replaced.Photos:Paul Marlowe, Marlowe Restorations.
replacement, other opinions should be sought to ensure
repair is truly not feasible. Preserving the historic
appearance of old columns is not the same as preserving
historic columns.
Where a replacement turned or staved column is
needed, a local millwork may be able to match the
profile or pattern. Alternatively, the Internet is helpful
in identifying potential sources of replacement columns
that can match the appearance of the remaining ones.
Replacement Materials
Wood
When selective replacement is necessary, the key to
success is the selection of suitable wood. Dimensional
stability, decay resistance and paint holding ability are
wood characteristics that effect durability. Wood that
expands and shrinks too much can cause paint to crack.
Substances found naturally in certain kinds of wood
repel fungi and insects that destroy wood. Selecting
wood that is relatively stable and naturally decay
resistant helps avoid problems.
The wood from trees cut one and two centuries ago was
much different than most wood available today. The
mature trees in older forests grew very slowly and, as a
result, the annual growth rings were very close together .
Today, trees grown by commercial companies for their
lumber are fast growing so they can be harvested
sooner. As a result, commercially farmed trees have
annual growth rings much further apart, resulting in the
cut lumber being less strong and decay resistant than
older timber. These differences in quality are one of the
reasons it makes sense to save old wood when possible.
Wood Selection: When choosing wood for repair
and replacement work, the species, grade, grain
and environmental impacts should be taken into
consideration. This is especially applicable to historic
porches because of their high exposure to the weather
and vulnerability to decay. The best species are
those with good natural resistance to decay, such as
redwood, cypress, cedar or fir. A clear (knot free)
grade of wood is best; however, if clear wood is not
readily available or too expensive, a grade with small
or tight knots is acceptable. Finally, the use of more
stable vertical grain lumber is preferable to flat grain
boards. Vertical grain lumber expands and contracts
less with changes in moisture content, resulting in
reduce warping and checks. Paint thus will hold better.
The downside to using vertical grain boards is the
cost, which tends to be as much as two to three times
the price of flat grain lumber in the same grade and
species. However , this expense is typically recovered
through lower maintenance costs over the years. Thu s,
a decay-resistant, high-grade, vertical grain lumber
is the best choice for the replacement of deteriorated
porch elements, particularly flooring, stairs and milled
elements such as balusters and moldings.
The best species to choose will vary depending on the
region the house is located. For example, in the South,
cypress is more available, making it the selection of
choice in the region. Because of this wood's relative ease
with which a carpenter can shape it, cypress is a good
choice for replacing brackets and trim boards on a porch .
In contrast, vertical grain Douglas fir is less workable,
but is a very good choice for the replacement of porch
floorboards in most climates. Although Douglas fir is
from the Northwest, it is generally available throughout
the country. For most protected trim boards on porches,
white pine is a good choice as it is easy to work and
is moderately decay resistant, especially if the wood
is back-primed before installation. Availability of any
specific wood will change annually based on market
suppl y and demand.

Wood Characteristics
Species
Redwood
Cut or Grade
Clear, Vertical-grain,
all-heart
"B" Select, flat-grain
Resistance to
Decay
Resistance to
Cupping
Paint Holding
Ability
Cost Workability
$$$ Fair Excellent Excellent Excellent
$$ Fair Excellent Good Good
Cedar Clear $$ Fair Excellent Good Fair
Cypress Clear $$ Fair Excellent Fair Good
"C" & better ,
Vertical-grain $$ Fair to Poor Good to Fair Excellent FairDouglas Fir
"D" Select, flat-gra in $ Fair Fair Good Fair
Southern
Yellow Pine Vertical-gra in $$$ Fair Fair Excellent Fair to Good
Poplar Firsts and Second s $ Good Poor Good Fair
American
Mahogany Clear $$$ Excellent Excellent Excellent Good
This table summarizes the characteristics ofjust afew of the different species available,includingthe workabilityof the wood(indicating
a better woodfor decorative porch pieces),the resistance to decay (an importantfeaturefor all porchcomponents), resistanceto cupping(a
wood highly resistant to cupping is a better choicefor floor board replacement)and paint holdingability. The Cut or Gradeis alsolisted,as a
low-grade woodcan perform very differently than a higher grade in the samespecies. Costwill vary dependingon regionand marketsupply
and demand. In general, it is best to contact two or three local lumberyards tofind the availablewoods with the characteristicsneededin the
local market. Source:PracticalRestoration Report, ExteriorWoodwork Details.
Chemically Treated Wood : Chemical wood preservative
treatments are available to resist insect and fungal
attack, but care should be taken to avoid using ones
that may cause environmental or health risks. Borate
preservatives can be applied to surfaces or injected to
penetrate and protect the entire volume of the wood.
Preservatives with zinc napthenate can be applied to
the wood surface, where necessary, especially to protect
hidden joinery and the end grains of wood. Water-
repellants can also be used to help seal out moisture.
Finally, primers and paints should be applied to both
protect the wood and to maintain the historic character
of the porch. Note that these treatments are different
than those used on most pressure-treated wood, which
is typically a plantation-grown southern pine of lower
quality that is impregnated with chemicals. Pressure-
treated lumber can be effective when used for hidden
structural members like posts, joists and sills. However,
because typical pressure-treated wood is very susceptible
to the deterioration of checks, warping and splitting,
especially when left unpainted, it is not a good substitute
for the better quality wood that is needed for visible
finish porch parts.
Stock Components
For over a century, prefabrica ted architec tu ra l par ts have
been sold through catalogues or at home imp rove ment
stores. Some companies still make generic, stock
architectural componen ts in the same general sizes
and designs as those that were first man ufactu red .
These componen ts can be available in both wood and
substitute ma terials. Thus, it may be possi ble to replace
a historic stock component, such as an archi tectural
grade column, with a new prefa bricated column that
matches the original. Unfortuna tely, these rep lacement
parts are not designed to ma tch the historic p arts of
any particular porch. Becau se tradi tionally there were
many differen t porch elemen ts, a wide range of styles
and considera ble regional variations, stock replacement
parts available tod ay are no t often found to m atch what
is needed in a specific porc h repair project. When faced
with deteriora tion of a few porc h par ts, all the his toric
material should not be removed in favor of a readi ly
available stock design that does not ma tch the his toric
appearance. The expressed goal may be to crea te a porch
with a "consis tent look," bu t this approach diminishes
the building's his toric character and authen ticity.
1 'l

14
Plastic and Composites
A variety of modern materials are marketed today as
a substitute for wood. They are usually composite
materials typically in the form of plastic resins ,
including vinyl (PVC), fiber-reinforced polymers and
polyester resin. There are other products on the market
as well, including medium density wood fiberboard
and composite fiber-cement boards. The market is
ever changing with the introduction of new synthetic
materials and the re-formulation of existing ones. The
more costly synthetic products tend to offer the best
potential for matching historic features while offering
good durability . This means that potential cost savings
over new wood tends to be more long term than
immediate. Such products generally are not carried in
local home improvement stores but rather are available
from building supply companies or direct through
catalog sales.
The historical significance of a particular property and
its porch influences decisions regarding possible use
of substitute materials. In general, greater emphasis
is placed on authenticity and material integrity when
maintaining and repairing individually significant
historic properties. However, a front porch that is
repeated on rowhouses may be one of the defining
characteristics of the historic district and thus of
importance to the entire streetscape. So, too, can the
location and appearance of a porch influence material
decisions, as with, for example, a prominent front porch
with ornate detailing as opposed to a small porch over a
rear door.
Thus, when the historic porch contributes to the historic
character of a building, the particular substitute material
that is being considered should accurately match the
appearance of the wooden feature being replaced.
Composite materials that can be routed or shaped in the
Figure12. This old porch
enclosure, locatedon the backside
of a house, has acquiredsignificance
over time and is remarkableboth in
the appropriatenessof its detailing
for use by others today, as well as
its high degreeof maintenance.The
enclosureis set behind the columns;
the balustradehas been retained;
and the light divisions and the size
of the glass panes echothat of the
windows above. Within eachbay
thereare two well-crafted, inward
swinging doors, providingfor
greaterseasonaluse of the porch.
Photos: Charles Fisher.
field to match specific pieces being replaced have greater
potential for use in repairing a historic porch . Materials
that cannot be shaped to match the visual appearance of
the historic pieces being replaced usually are not suitable
for use on historic buildings.
Substitute materials need to be finished to match the
appearance of the historic elements being replaced. In
nearly all cases, this means that the material should be
painted, or where historically appropriate, stained as
with some porch ceilings. While there are substitute
materials being marketed as pre-finished with either a
plain flat surface or generic wood-grain texture, select
those that can be painted or stained in the field.
When a substitute material is to be used in conjunction
with existing or new wood material, it is important to
consider the differences in expansion and contraction
due to temperature and moisture changes. Before
making a decision, it is also important to understand
how a particular substitute material will age, what its
maintenance requirements are, and how the material
will deteriorate. For example, sunlight can break
down exposed surfaces of plastic resins, so painting
the surfaces is needed just as with wood. Low and
medium density plastic foam parts are easily damaged
by abrasion and physical damage, exposing the interior
foam to weathering.
Wood porches are just that, porches made out of wood,
just as a brick houses are made of brick and cast-iron
porches are made of cast-iron. The type of materials
used historically in the construction of a building helps
define its character. Limited use of substitute materials
that closely match missing or deteriorated features
may not endanger this historic character, but wholesale
replacement with substitute materials usually will.

Considerations for Contemporary
Alterations
Enclosures
Much of the character of a historic open porch is clearly
its openness. Therefore, in most cases, a historic open
porch should not be enclosed. If a porch enclosure is
being considered, its significance and location-as well
as the nature of the planned enclosure-play key roles
in whether it can be done without changing the porch's
and building's historic character. While it is almost never
appropriate to enclose a front porch on a historic building
to create interior space, enclosing a less prominent
porch on a less visible elevation could have less impact.
In addition, an enclosure should retain as many of the
historic porch features as possible (Fig 12).
Insect Screening and Awnings
Traditionally, the seasonal use of porches was extended
with screens and awnings . Screened porches have
been popular since the advent of inexpensive and
durable wire insect screening in late 1800s. Screens were
often set unobtrusively behind railings and columns
so the decorative components of the porch remained
prominent and visible. Since screens can be damaged
easily, the screening material was often set in slender,
easy to repair, removable wood frames that could be
installed during the warmer months, and stored in the
winter . When screening a porch today, this historic
precedent is recommended. Screened panels should
have minimal wood framework painted either to match
the porch or in a darker color to make the framing less
visible . Decisions on whether screens should be installed
inside the porch railings and posts, between the posts, or
on the outside will depend on local traditions and on the
design of the porch and trim. Screen doors on porches
should be sized to fit proportionately with the porch,
made of wood, and hung to swing out so insects are not
brought inside with use.
Awnings, drop curtains, and valances were common
porch accessories during the nineteenth and well into
the twentieth centuries. Both functional and decorative,
these canvas features helped shield porches from the
sun's direct rays, while their colorful stripes embellished
and complemented the house's exterior. Some awnings
were fixed in place; others were of a roller assembly that
allowed owners to easily lower or retract the awning,
depending on weather conditions.
Today, modem solution-dyed acrylic fabrics-materials
that resemble, but are more durable than canvas-are
often used on porch awnings and drop curtains.
When new awnings are installed on a historic porch,
the selected awning should be appropriate in shape ,
material, size and color. Care should be used not to
damage existing historic porch features such as columns
or cornices .
Temporary Enclosures
Temporary enclosures allow a porch to be used in colder
months while not permanently altering its appearance.
In fact some have become historic features of buildings.
Particularly in New England, there is a continuing
tradition of installing relatively substantial glass and
wood panels on porches during the winter, especially
around an entrance door. These tended to have small
divided lights. Sometimes porches were fully enclosed
with a divided light glass door for entry, creating an
enclosed vestibule that reduced the amount of cold air
entering the house when the door was opened. Others
consisted of simple sidewalls perpendicular to an existing
entrance door, serving as a windbreak. Such enclosures
were generally removed in the spring (Fig. 13).
In recent years, some porches have been enclosed during
the winter with plastic sheeting (polyvinyl) for perceived
energy conservation or for creation of an enclosed space.
Such a treatment generally diminishes a building's
historic character and is not recommended for highly
visible porches.
New Permanent Enclosures
Enclosure of a historic porch can result in significant
changes in the appearance and character of the building.
When considering the possible enclosure of a porch, a
number of questions and concerns should be successfully
addressed.
Is the porch on a significant elevation of the building?
A porch on a prominent elevation was there to be seen
and its open qualities are visually important. Enclosing
such a space should be avoided.
Figure13. Particularlyin New England, thereis a coldweather
traditionof installing temporaryglass and woodpanelsat entrance
doors,therebycreatingan enclosedvestibule. Theseenclosureswith
their small dividedlights weregenerallyremovedin the spring.
Photo: John Leeke.
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16
Figure14. The enclosureof a prominent porchcan dramaticallychangethe historiccharacterof a building. The L-shapedporchon this 1896
Shingle-sti;leNew England residencewas laterenclosedwith aluminum windows and screens. Recent owners electedto reopenthe historicporch.
Among the other work, it was necessaryto correctstructural damage,as with this post, wherebeneaththe wood casingcarpenterants had done
seriousdamage. In reopeningthe porch,the historiccharacterof the residencehas beenbroughtbackand the traditionaluse of the porchis once again
enjoyed. Photos:Mark Landry,LandmarkServices.
Is the enclosure necessary? An enclosure will
undoubtedly change the porch as a historic feature
and may result in damage or loss of historic materials.
Depending on the significance of the porch and the
nature of the building, a new porch enclosure may
also change the historic character of the building.
Consideration should be given to alternate solutions
such as recapturing underutilized space in an attic or
basement (Fig 14).
Is the porch a highly distinctive feature of the
building? Even porches on secondary and rear
elevations can be distinctive, such as a two-story porch
on the side ell of a farmhouse. Porches ornamented
with decorative trim that embellishes the house can also
be distinctive. Enclosing these features should also be
avoided whenever possible.
Is the porch a feature repeated on a row of buildings
in a historic district? Open front porches on a block of
row houses can be not only important to an individual
building but can also make up a significant feature
of the streetscape. Enclosing such a porch usually is
inappropriate even if a porch on an adjacent building
already has been enclosed.
Will the proposed enclosure encompass the entire
porch? History has shown that the enclosure of a
portion of a porch on a secondary elevation does not
always alter the character of a building. In the past
as indoor plumbing was introduced to old buildings,
the partial enclosure of a one or two-story porch
on a secondary elevation was a convenient means
of providing new bathroom space while limiting
disruption to the building's interior. Since early
bathrooms were traditionally small in size, most of the
existing porch could be retained as open space. It was
common to create new walls set either between columns
or behind them, since the columns usually served a
structural as well as decorative purpose. Where sleeping
porches with full-length louver shutters were present,
the new wall could simply be set behind and the shutters
retained and fixed in place. In both cases the resulting
effect minimized the impact of the partial enclosure
on the appearance of the building. This also provides
us with an approach that may be appropriate for a
particular project today.
Will the enclosure result in the loss of considerable
historic fabric? Unless the historic porch is so
deteriorated that it is beyond repair, any consideration
of enclosing all or part of a porch should incorporate
retention of historic fabric. This may mean that the
existing structural system needs to be augmented but
generally not replaced. Distinctive features such as
columns, brackets and balustrades should be retained
and the new wall set behind them.
Is the foundation adequate for the enclosure of the
porch and the new use of the space? Porches were often
built on simple posts or piers, some with only minimum
footings. Such structural supports may be inadequate
to carry the added load of the proposed changes and
the typical low space beneath a first floor porch may
make installing a new porch foundation difficult and
expensive. Such installations may result also in an
extensive loss of historic fabric.
How will the proposed enclosure be viewed from the
outside once the interior space is furnished? One of
the approaches to enclosing a porch is to utilize near
full glazing set behind existing columns in an attempt
to retain a feeling of transparency. Whether such a
treatment is successful depends on how it will look
once it is constructed and how will the appearance
on the outside be impacted by interior lighting,

mechanical systems and furnishings. The traditional
use of plantings and porch awnings for shade also
provided extended privacy. If historically appropriate,
an existing or new awning and plantings may help to
reduce the impact of a porch enclosure on a secondary
but visible elevation.
Is the design of the proposed porch enclosure in
keeping with the historic character of the building?
Where the enclosure of all or part of a historic porch
is appropriate, the selection of a compatible design
and materials is important. Windows, doors, and wall
material selection, along with how the new infill fits
within the existing porch, are all factors to consider. A
traditional technique of porch enclosures still used today
involves the insertion in each column bay of one or more
glass enclosures set in wood frames. The enclosures
are located between or behind the columns, depending
upon the nature of the porch, and mimic the pattern or
size of glass panes found in historic windows on the
building (Fig 15). An alternate treatment involves the
use of much larger sheets of clear, non-reflective glass
recessed behind the porch supports, balustrade and
railing. This more contemporary treatment may be
appropriate, depending upon the historic character of
the building, location of the porch, and other factors (Fig
16). Windows, doors, and wall material selection, along
with how the new infill fits within the existing porch, are
all factors to consider .
Safety and Building Codes
There are many building codes used by states and
municipalities across the nation, with a majority of their
requirements being very similar and focused on new
construction. Building codes such as the International
Figure 15. A traditionaltechniqueof porchenclosuresstill used
today involves the insertion in eachcolumn bay of one or moreglass
enclosuresset in woodframes. This enclosureis properlyset backan
entire porchbayfrom thefront of the house and utilizes traditional
light divisions and woodframes. The balustrade,added herefor
illustrationpurposes,shows the importance of retaining this linear
feature within the enclosedbays. Photo:CharlesFisher.
Figure16. The use of nearfull glazing to enclosea porchmay be
appropriatedependingupon the historiccharacterof the building,
locationof the porch, how the interiorspaceis to be treated,and
otherfactors. This enclosureof a rearporchto createa conference
roomsuccessfullyutilizes largeexpansesof glass and narrowmetal
framing set behindexisting porchelements(a throughe). Wherean
additionalhorizontalsupport was needed(J),theframe was placedat
a locationthat is found in many traditionalinsect screenenclosures.
Photo:CharlesFisher.
Building Code and its companion, the International
Existing Building Code, have been developed in recent
years that are generally much more sensitive to existing
and historic buildings, emphasizing the retention of
historic fabric without jeopardizing life safety. These
"proportional codes," as they are called, allow building
inspectors greater flexibility to make decisions based on
the specific circumstances of each building, and the type
and extent of work planned.
Successful rehabilitation work achieves a balance
between building and safety code considerations and
the retention of historic design and materials. The porch
is no exception. The most common porch elements
affected by code requirements are railing/balustrade
height, baluster spacing, stair geometry, and structural
system. When a historic porch is so deteriorated
that a substantial portion must be replaced, modern
building code requirements are usually triggered. These
requirements are often more stringent for multi-family
or commercial structures than single-family houses.
17

18
Figure17. The porch's structural system must be capable
of supporting today's loads. In this casemoisture led to the
deteriorationof the woodgirderat the corner,creatinga major
structural deficiency(top). A new solid timberwas installedto
replacethe girder (middle);alternativelya built-up girder couldhave
beenused since afascia boardwould concealit. The column base was
repairedand portions replacedand the balustradeand column reset
and secured(bottom). Photos: Paul Marlowe,MarloweRestorations.
It is important to ensure that the code-required work
be done in a manner that is sympathetic to the historic
character of the building. If building code requirements
threaten the historic character of the porch, alternatives
that reconcile the two should be explored. Many local
jurisdictions issue waivers or variances for historic
buildings, allowing for historic elements to be retained,
when it can be demonstrated that safety will not be
compromised.
In the event that an alteration to a historic porch is
required to make the porch safe to use, care should
be taken in planning and undertaking the work.
Fortunately, there are usually a number of options
that are possible, although one is usually the most
appropriate preservation solution.
Structural Loads
Ensuring that the structure's foundation can support
the specified load is a primary safety issue for porches.
Fortunately, repairs and upgrades to improve structural
stability are generally made to the foundation at or
below grade, and can usually be concealed under the
porch or behind finish details. Weakened joists can often
be strengthened with the addition of sister joists, epoxy
structural repair, or the insertion of new concealed
structural members (Fig. 17).
Stairs
Historic stair risers are sometimes too steep and treads
too shallow to meet contemporary building codes or
the special needs of the occupants. In the latter case,
the addition of a simple handrail that meets code may
suffice. In instances where there is another stairway that
meets code, for example a side stair, it may be possible to
retain the existing non-conforming historic stairway.
Modifications to bring porch stairs into conformance
with code can be difficult. Where buildings are set close
to the street, it may not be possible to rebuild the stairs
in the same direction to meet code if they will have to
extend onto a public sidewalk. Unless a variance is
obtained, it may be necessary to turn the stairs to be
parallel rather than perpendicular to a building. Where
wood stairs need to be rebuilt, the historic finish details,
such as moldings, cut work and edge detailing, should
be reflected in the new construction. One common
mistake is the replacement of wood stairs or brick steps
with concrete, a material that may not be in keeping
with the historic building.
Where a porch must be used as a wheelchair accessible
entrance, two general issues arise. If there is an elevation
difference greater than ½- inch between the porch deck
and the front door threshold, a simple threshold ramp
may suffice. In cases where the elevation difference is
larger than can be accommodated by a simple threshold
ramp, a level platform with sufficient turning radius at
the door for a wheelchair may be necessary. The other
issue is devising a means for wheelchair access from
the grade to the porch deck when the porch is the only

Figure18. When a porchis used as a wheelchairaccessibleentrance,it may be possibleto retain the historicstairs by addinga ramp parallelto the
building. Throughplantings and some re-grading, the new ramp built parallelto the building (left) allowsretentionof the historicstairs and does
not impact the historiccharacterof the entrance(right). Photo:Iowa State Universih;Extension.
entrance alternative . It may be possible to retain the
hlstoric stairs by adding another entrance to the porch
with the construction of a ramp parallel to the building
(Fig. 18).
Baluster Spacing
Codes generally require for children's safety that new
balusters are spaced such that a four-inch sphere cannot
fit through. Vertical balusters on older porches are
often spaced farther apart than thls. If modifications
are required, inserting narrow metal rods between
the existing balusters may be a compatible and
inconspicuous solution, particularly if painted flat black
or another dark color. This is generally preferable to
moving the balusters closer together or adding more
balusters to fill the gaps.
Railing/Balustrade Heights
Historic porches generally have handrails that measure
28 to 30 inches in height from the floor. Current code
requirements for new construction generally mandate
that railings be 36 to 42 inches in height (often 36 inches
for single family dwellings, and 42 inches for multi-
family dwellings and commercial buildings). Raising
the hlstoric railing by as much as 30% or more can
have a major impact on not just the proportions of the
balusters, but also on the overall appearance of a hlstoric
porch. Adding a simple rail above the hlstoric railing
and painting it to rude its presence as much as possible
is generally the least intrusive solution when thls safety
requirement must be met. Similarly, an existing bottom
rail is sometimes set too hlgh off the deck to meet
contemporary code requirements. The addition of a
simple wood rail or even a narrow metal pipe below the
bottom rail will usually suffice (Fig 19).
It is not uncommon to find historic porches with
decks only several steps off the ground and with no
railings. For owner-occupied residences undergoing
rehabilitation, local codes usually will not require the
addition of railings to these existing porches, provided
the porch deck is below a certain height off the
ground-typically from 18 to 24 inches. Where greater
safety is warranted even though no railing is required,
alternatives such as planting an adjacent hedgerow,
installing planter boxes between columns, or raising
the grade are worth considering. Where not practical
or acceptable, a railing might be added so as to not
noticeably impact the appearance of the historic porch.
Any solution, however, should be simple and based on
the character of a specific porch, and its appropriateness
considered on a case-by-case basis.
Figure19. Historicporchesgenerallyhaverailings that measure
28 to 30 inches in heightfrom thefloor. When additionalheight is
necessaryfor safeh;,a simple rail, addedfor illustrationpurposes
in this photograph, can usually be installedabovethe historic
railing. Not only does this treatmentallowretentionof the historic
balustrade, but it alsohas a minimum impact to the appearanceof the
porch. Photo:CharlesFisher.
19

Conclusion
Wood porches have made an enduring contribution
to our built environment. Porches are significant
because of the special character they impart to a historic
building and their role in our social and cultural
history . A porch is an open sheltered part of a building,
providing a covered entrance and, where larger,
serving as an outdoor activity room. It represents an
outward extension of a building, a place guests can
initially be shel tered from the weather, even welcomed
and entertained.
Like all historic building features, wood porches require
routine maintenance to prevent decay. Understanding
how a porch is put together and the factors that
cause deterioration will help considerably in carrying
out both maintenance and needed repairs. Regular
maintenance pays off not only with a good appearance
but also by reducing the need for future repairs . With
both main tenance and repairs, emphasis should be
placed on preserving the historic fabric and significant
features of a porch. Where components are deteriorated
beyond repair or missing altogether, new pieces should
be installed that match the historic ones. Fortunately,
good craftsmanship and the use of quality replacement
mater ials as needed will be rewarded with repairs that
last. Atten tive care will result in the historic porch
retaining its charm both in appearance and in function .
Acknowledgemen ts
Bibliography
Davis , John Michael. "Exterior-Trim Details That Last," Fine
Homebuilding, August/September 2001.
Fisher, Charles E. and Hugh C. Miller, eds., Caringfor Your
HistoricHouse, New York, NY: Harry N. Abrams, Inc ., 1998.
Kitchen, Judith L. Caringfor Your Old House:A Guidefor Owners
and Residents,Somerset, NJ: John Wiley & Sons, Inc., 1991.
Leeke, John C. PracticalRestorationReports Compendium,
Portland, ME: Historic HomeWorks, 2005.
Nash, George . "Renovating Old Porches: Common Problems
Can Be Solved With Simple Repairs," FineHomebuildi11g, July
1982.
Preservation Brief s, Washington, DC: National Park Service ,
Technical Preservation Services: 1978-present.
Preservatio11Tech Notes, Washington, DC: National Park Service,
Technical Preservation Services: 1984-present.
Reed, Douglas C. "Detailing Early Porches ," Old House Journal,
May/June 2001 and July -August 2001.
Visser, Thomas D. Porches, Piazzas & Verandas, forthcoming .
Weeks, Kay D., and Anne E. Grimmer . The Secretaryof the
Interior's Standardsfor the Treatment of HistoricProperties
with Guidelinesfor Preserving, Rehabilitating,Restoring&
Reconstructing Historic Buildings,Washington, DC : National
Park Service, 1995.
John Leeke is a Preservation Consultant in Portland, Maine; Aleca Sullivan is an Architectural Historian in Evanston, Illinois. Cover
illu stratio n: In diana Historical Society, Jay Small Postcard Collection , Standard Cottage, 1886, Bethany Park, Indiana, Collection No.
P0391, digi tal image C 2003.
Numerous individua l generously provided their time and shared their knowledge in making this PreservationBriefpossible. Thomas
D. Visser, Historic Preservation Program, University of Vermont, deserves special recognition for his insightful contributions . Also
gratefully acknowledge for their assistance in reviewing this publication are Neal A. Vogel, Restoric LLC and Judith L. Kitchen, Ohio
Sta te His toric Preservation Office. Thanks go to Marilyn Kaplan , Preservation Architecture, for her contributions to the code section
of this pu blication. Special thanks also go to the following staff of the National Park Service's Technical Preservation Services office for
their review and assistance: Sharon Park, FAIA, Michael Auer , Anne Grimmer , and particularly to former staff Kay Weeks. Thanks also
go to Chad Randl, Kaaren Staveteig and Liz Creveling of the National Park Service's Technical Preservation Service for their assistance
and to Peter de Paola, Mark Landry of Landmark Services, and Paul Marlowe of Marlowe Restorations.
This publication was under the technical and editorial direction of Charles E. Fisher of the National Park Service's Technical
Preservation Services whose considerable contributions , including that of the section on new permanent enclosures, helped made this
publication possible.
This publication has been prepared pursuant to the National Historic Preservation Act, as amended, which directs the Secretary of
the Interior to develop and make available information concerning historic properties. Comments about this publication should
be addressed to: Charles Fisher, Technical Preservation Publications Program Manager, Technical Preservation Services-2255,
National Park Service, 1849 C Street, NW, Washington, DC 20240. This publication is not copyrighted and can be reproduced without
penalty . Normal procedures for credit to the authors and the National Park Service should be provided. The photographs used in
this publication may not be used to illustrate other publications without permission of the owners. For more information about the
programs of the National Park Service's Technical Preservation Services see our website at www.cr.nps.gov/hps/tps
October 2006