Painting and Stripping Old Wood Siding
Step-By-Step
Here are the step-by-step procedures in painting original wood
siding on an historic house as discussed in our Painting and Stripping Old Wood Siding—Overview page.
Strip the old paint using an infrared
paint stripper for large areas and a heat gun for hard
to reach areas.
More information on our paint
removal page.
Remove any caulk between the boards of
the siding. In old houses, caulking between boards
will trap in moisture that can cause the paint to peel.
In the photo on the right, you will see wooden plugs
use to cover the holes drilled to blow in insulation.
We reset all of the plugs by removing them, applying
polyurethane glue (Gorilla Glue), and resetting them
in the siding so that they were flush. Even better is to
use a wood epoxy like Abatron LiquidWood. What doesn't
work is to use a regualr wood glue or wood filler. |

Using an infrared heat paint stripper
|
| Scraping. We used a good carbide blade triangular scraper
we purchased from the firm selling the infrared paint remover
we use. |

Scrape and then sand to removed any
weathered surface. On our siding, the wood actually weathered
under the peeling paint. Paint will not hold to weathered
wood. |
Nail any loose boards. We removed the old
cut nails from 1860 because they no longer gripped well.
We replaced them with stainless
steel siding nails.
Sand. We used a palm sander with
course 40 grit cloth backed sand paper. |
Modern paints, on the other hand, are primarily bonding
paints with little ability to penetrate a substrate. For
this reason, surface preparation is extremely important for
today's paints.
Before preparing the interior for repainting, all moisture
penetration from failing roofs or gutters or from faulty
plumbing or interior heating elements should be identified
and corrected. A paint job is only as good as the preparation
that goes before it. The surface to be painted, old or
new, wood, plaster, masonry, or metal must be made sound
and capable of taking the paint to be applied.
National
Park Service Preservation Briefs |
| Patch any surface holes with an exterior wood filler.
We used Dap
Wood Dough for small holes and surface cracks. We now use
an epoxy filler for all holes, large or small (See
below). You want to use Epoxy filler that has
the same expansion properties as wood and doesn't shrink
when it cures.
Do a final sand with course
60 grit cloth backed sand paper.
Because older wood framed homes are not rigid, wood fillers
can work loose over time. For this reason, we were careful
to use the epoxy filler on large holes and to caulk
thin cracks using the flexible, paintable silicone caulk.
Note: Use
an epoxy filler designed for use
on wood (two are recommended below)
so that it will have the same expansion characteristics
as the siding. We don't think it is cost effective to use
cheaper auto or marine epoxy fillers. |
Wood putty filled hole.
The nail hole will be primed and caulked over.
Damaged board first stabilized
with liquid epoxy, e.g., on soft wood, cracks, and edges
that will contact water. Epoxy filler is then added to
cracks and large holes. Regular wood filler is used for
small indents. |
Prime exposed nails. If rusted, use the correct rust primer,
or better, use a rust converter. This is a chemical that
converts rust into a neutral coating.
Another option is to replace original nails with stainless
steel nails. |
|
Apply a coat of wood preservative on any wood sections
not coated with the liquid epoxy. We used Wolman's
Zinsser Woodlife Classic .
To use a preservative, the siding must be free of paint
so that the preservative can be absorbed by the wood.
Use an epoxy consolidant instead of the preservative
where the wood is soft (See
below). We painted all of the the window trim using
the epoxy consolidant as this provides the best water
protection and paint bonding. The epoxy
consolidant is too expensive to coat all the siding.
We have also learned of Smith and Co's epoxy primer, MultiWoodPrime
Note: Be sure to paint on the epoxy consolidant
before painting on the wood preservative. Don't bother
to use the preservative on any painted or epoxy consolidated
wood. It won't be absorbed. |

Paints containing linseed
oil are very susceptible to mildew. Of
the available water-base paints,
acrylic latex is the most mildew
resistant. Porous latex paints applied
over a primer coat with linseed oil will
develop severe mildew in warm,
damp climates. |
Caulk cracks after the preservative has dried. We used GE
XST Extreme Paintable Silicone II (We
are now uinsg GE
Groov caulk ). It is important
to either caulk any large open crack or use the epoxy
filler. Don't use regular wood filler as it may not
hold up as the siding moves over time. We also caulked
over the primed nail heads.
Don't caulk the bottom of
the siding so that moisture coming out of the house can
escape. |

Long cracks also can be caulked instead
of using an epoxy filler. |
Apply one coat primer. We are using ZINSSER 1-2-3 primer
as it dries faster and looks like it has better properties
than regular oil based primers.
Tip: Have the paint
store tint the primer to the same color as the top coat. |
- Don't let the primer
sit more than a few weeks before painting. Soap-like
compounds can form on oil primers in as little as two
weeks.
- Use a brush when painting
old siding. It allows the paint to be worked into
the siding's imperfections more effectively than a roller
or spray.
- Don't prime or paint in
direct sunshine, when it is dry and breezy, or is very
hot (over 90 degrees F)
- Paint should not be
applied when the air temperature is below the stated
figure for the product, nor if the temperature is forecasted
to drop below that minimum during the next 24 hours,
nor if the surface being painted is below that temperature:
Oil-based paints should be applied when the temperature is at least 40 F;
for latex paints, the temperature should be at least 50 F.
When pretreating
the wood with a paintable water-repellent preservative (a recommended practice),
best results are achieved if it is applied when temperatures are greater
than 70 F.
- Don't paint if it is
too humid (between 20% and 80% is ideal). When water-based
paints cure, the water should evaporate as fast or faster
than the solvents. After the water has evaporated, the
paint will shrink to nearly its final shape. As the solvents
evaporate, the paint chemically reacts to form a hard
material. When it is too humid, water cannot evaporate
and the solvents may evaporate first, causing the paint
to cure while still in a water-filled state. You cannot
recover from this type of disaster. Oil-based paints
will also fail if conditions are too humid.
|
Apply two coats of Pratt
& Lambert Exterior Acrylic Latex Eggshell .
When I buy paint, I try to use the top rated on in Consumer
Reports figuring at least there is a test behind the
paint.
We were lucky to fine a local supplier of California
Paint's 2010 100% Acrylic latex exterior which we just used for
the final side of our house. This paint has been top rated
by Consumer
Reports for years. |
Epoxy fillers and consolidants
Abatron's
LiquidWood and WoodEpox
These products restore rotted,
severely damaged windows, columns, frames, broken furniture,
structural and decorative wood components. They are especially
valuable for parts that cannot be replaced because of size,
shape or other reasons. The objects restored with these products
become fully functional parts often stronger and far more durable
than the original.
The consolidants (penetrants). Reinforces, rebuilds, water-
and insect-proofs wood by hardening after penetrating. Regenerates rotted windowsills,
frames, structural and decorative parts, furniture, boats, columns, floors.
Epoxy fillers are a structural adhesive putty and
wood replacement compound. They are a high-strength no-shrink adhesive paste
to fill, repair and replace wood and other materials in structures, walls, floors,
furniture, sculptures. They are unaffected by water and insects.
Rot
Doctor's Penetrating Epoxy and FILL-IT™ Epoxy Filler
Smith
and Co's MultiWoodPrime epoxy primer
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