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A Good Perch Is Important
Substantial scaffolding is a must for optimum production in prep and painting. We combined standard 5'-wide frames with aluminum and plywood platforms, screw-jack base plates, and horizontal braces. Adding outrigger brackets to the platforms created a continuous surface that was a boon to painting. Scaffolds with 7'-long platforms are easier to erect than 10'-long platforms and more versatile around window bays and other façade protrusions.
We kept enough frames on hand to assemble at least two scaffold bays so that we could "leap frog" the setup along the façade by disassembling and assembling adjoining bays. Although some people prefer pump-jack scaffolds that suspend planks from 4x4 posts, they're prone to swaying, movement that can drastically affect the quality of the final surface when working with paint shavers.
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Getting Under Second Skins If you apply tools and materials with a production-minded approach, it's possible to restore exterior paint and woodwork with like-new results. By Gregory Macneil

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Before removing vinyl or aluminum siding, assess what's underneath. While ovecladdings can stabilize historic exteriors, when they're gone there's still the effects of their installation to deal with, as well as any original paint problems.
Photo Courtesy of Gregory MacNeil
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Back in 1997, when I bought some woodlands on the
southern Atlantic shore of Nova Scotia, I also became the
owner of a small 1916 farmhouse and its little outbuildings.
Though the balloon-framed house was structurally
stable, it had been covered in the late 1970s with vinyl
siding and aluminum storm sashes, and like many preservationminded
folks might do, I discounted it at first. Surely, the historic
siding was decaying from the inside out because of the moisture
trapped behind the vinyl veneer and, no doubt, any decorative
details had been ruined beyond repair by the installers. In fact, I
was so positive that the building was secretly self-destructing that
I ordered two pallets of replacement wood shingles and proceeded
to peel off the siding before it could do any more damage.
To my surprise, many of my assumptions proved largely
untrue. I found no rot under the plastic second skin, just the reason
for the installation in the first place: a shingled exterior in need of
a thorough prep-and-paint job.What's more, the damage from the
siding installers was substantially less than I expected (after all,
they do no more than what's needed to flatten walls for speedy
residing). Ultimately, restoring the shingles, windows, and other
parts of the farmhouse became a six-year preservation experiment
and a source of techniques and ideas that can be applied to many
old-house exteriors.
Stripping Decades of Paint
Removing paint from shingles is tricky. If you eliminate power
washing, sandblasting, and open flame, all of which are inappropriate
for stripping shingles, you're left with four paint-removal
methods: hand-scraping, chemical strippers, power paint shavers,
and infrared heating technology. I find that power paint shavers
combined with hand scraping can do the vast proportion of the job.
Traditionally, shingles installed with a 4 1/2" exposure are
scraped by hand. Considering that the most natural stroke for
hand-scraping is 12" to 18", scraping a third of this distance-the
traditional amount of shingle "to the weather"-is laborious, timeconsuming,
and inefficient. If you try to improve efficiency by
scraping wood shingles horizontally across their grain, you risk
tearing the shingle faces and edges, or even splitting the shingles,
especially if they're old and fragile.
Removing the vinyl siding revealed wood shingles-
surprisingly intact, but still due for repainting.
The siding installers' legacy included window sill
ends cut back to the casings (above) and headers
completely lost but for their paint ghosts (below).
If handled correctly, power paint
shavers can be very productive tools for
removing decades of paint with minimal
damage to the surface. Though some models
are best designed for working on surfaces
6" or wider, such as clapboards, others
are well-adapted to the smaller widths
of shingles. Then, by working horizontally,
you can remove a full 24" of paint from the
shingles with a single, efficient pass. In
fact, using two or three tools, with each
adjusted for progressively less aggressive
cuts, speeds production while remaining
sensitive to the wood.
For instance, we used two Metabo
724S shavers-one adjusted for an initial
rough cut and the other for a shallow,
cleaner cut-with the tool operators following
each other along the façade. The
objective was to remove only the bulk of
the paint with a pass of the first tool, and
then return for a pass with a second tool
to strip most of the remaining paint.
Although these tools are readily adjusted,
the cutting head depth marks become
harder to see as you use the tool, so
we set the depth once and labeled the
tools accordingly.
We practiced our technique first on a
nearby barn and found it was best to hold
the first tool horizontally and the second
tool either vertically or horizontally as
the undulations in the shingle surfaces
demanded. With a two-person crew, production
rates can exceed 450 square feet
per day.However, if you attempt to remove
all of the paint with these tools, you'll
invariably remove an excessive amount of
substrate.At this point we switched to hand
scrapers for any paint left within concave
surfaces, followed by a sash chisel and specialty
scraper to address shingle butts.
Another paint-stripping method we
employed was "wooding," an idea we borrowed
from the shipbuilding and repair
industry. Traditionally, a wooding tool is
made from a worn-out 10" or 12" mill file
that is heated, bent, tempered, and sharpened
to form a heavy ship scraper. The tool
is struck or tapped along the paint surface
to either scar or chip off multiple layers at a
time. We assembled our wooding tool by
attaching a common plane iron to the handle
of a carpenter's bench axe, thereby
improving balance and scraping power.
The key to the tool's success in both its traditional
form and our design was that its
weight dampened vibration and aided in
cutting and chipping. The tool excelled at
removing thick paint films from dense
wood substrates. In addition, because a
wooding tool can be used with only one
hand, your free hand can hold a cordless
vacuum next to the surface to easily move
around a building for small-scale, localized
paint removal.
After removing the paint, we finishsanded
the shingles using a random-orbit
sander equipped with soft contour hookand-
loop backer pads. Though the edges
of these soft pads degrade if you allow
them to touch the shingle butts, their
advantage is they conform well to the shingle
surface. (It's better to lose a few easily
replaceable pads than the shingles themselves.)
When used with only light pressure,
40-grit sandpaper leaves a good surface
for paint adhesion. For all our methods,
we made sure any tool operated with
two hands had built-in dust collection. For
single-handed tools, the user held a
vacuum hose with his free hand.
If you are removing vinyl or aluminum
siding from a building constructed
before 1978, you must assume that you'll be
dealing with lead-based paint underneath
until tests prove otherwise. With that in
mind, we worked with Tyvek suits, nitrile
gloves worn under standard work gloves,
and other personal safety equipment. The
latter included a positive-pressure, air-supplied
breathing apparatus equipped with
HEPA filtration, protection that is the next
step up from a half-face respirator.
Making Missing Parts
We initially expected that reconstructing
damaged or missing stylistic elements
would require a large volume of material,
especially given the appearance of the
house once we removed the vinyl siding.To
our surprise, the new material for missing
bed moulds, soffit brackets, window caps,
and the ends of window sills amounted to
less than half the payload of a compact
pickup truck. In fact,we restored all exterior
façades with lumber from a single tree
felled on the property, sawed on site with a
chainsaw mill, and then air-dried for a year
before use.
Like many vinyl-clad houses, the ends
of the 40 window sills on my house were
knocked off years ago so that siding could
be placed right over the window casing.
Rather than restore each end individually
with a hand-fit Dutchman patch,we developed
a jig that clamped to the sill face so
we could cut back the sill to a uniform
shape with a 1/2" plunge router. We set the
plunge cut to a depth just behind the window casing so that the joint was
almost completely weather protected. We
designed the jig to handle both left and
right sill ends and sized it for the narrowest
window in the house. We prepared in
advance replacement side overhangs for
the window sills to uniform dimensions.
With a two-person crew, we were able to
fit, install, and prime the 40 replacement
window sill ends in less than 14 hours.We
secured the precut replacement window
sill ends with two countersunk Spax
screws (fasteners that bore their own pilot
holes and come in lengths up to 7"), and
concealed the heads with epoxy plugs. One
pass with an electric planer along the sill
face and a few passes with a sanding block
was all that was needed for final cleanup
before priming and painting.
We documented many different
examples of 2 1/2"-wide window backband
profiles, both contemporary and period,
from nearby houses.However, finding consistent
examples of backband moulding
profiles on our house proved problematic.
Unlike crown mould and soffit brackets
that are full-bodied, backband mouldings
are finely detailed and the examples were
damaged from years of scraping and overpainting.
So, opting for some conjectural
restoration, we examined the shadows
associated with the historic profiles we collected
and then created a moulding profile
with a historically compatible shadow line
using an ogee raised-panel router bit along
with a 1/4"core box bit.
Preparation and Paint
To ensure consistent paint color and compatibility
between coats, it pays to choose a
reputable manufacturer and supplier.
When you purchase paint on an as-needed
basis for a multi-year project, you can
sometimes find minor color discrepancies
over time.Where possible, we primed and
top-coated the millwork made during the
winter months.We used an alkyd oil-based
primer with a 100 percent acrylic waterbased
top coat.
Because most substitute siding is
installed with 3"-long nails, it leaves the
original exterior peppered with nail
holes 16" to 24" apart in horizontal
courses about 8" above each other. We
filled these holes with exterior-rated,
two-part wood filler that sands and
scrapes easily, takes paint well, and does
not bleed through paint.
To paint the shingles we used a rolland-
brush method, first applying the paint
with a 4"- or 6"-wide "hot dog" roller,
before smoothing it out with a quality 4"-
wide brush. The long, 27" handle of the
roller reduces back strain, and the 1"
diameter roller is ideal for wetting the
butts and faces of the shingles. Plus, if you
can find Whiz brand rollers (originally
made in Germany), they are fully covered
on one end so that you can roll either vertically
or horizontally and still provide
good shingle butt coverage.We find that a
6" roller just about matches the output of a
painter following up with a 4" brush, so
that no member of a two-person team gets
ahead of the other.
In historic restoration projects we
like to date-stamp all new work with a
branding iron. Although we manufacture
our own branding irons, it's not hard to
find electric- and torch-heated branding
irons from woodworking supply houses
at reasonable prices. We typically brand
the work before applying the top coat of
paint. Though these branding marks are
not visible at a distance, upon close
examination they provide an in situ
record of all the repairs that helped give
an exterior a second life after being freed
of its second skin.
Gregory J. MacNeil is a partner in Jerry
MacNeil Architects Ltd. in Halifax, Nova
Scotia (902-445-3720).
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