John
Leeke's Historic HomeWorks™
Issue #34
Copyright 2007 John Leeke
Exterior
Paint & Clapboards
I live in an
old farmhouse in
Vermont
. The oldest part of the house still has it's original clapboards
that date to about 1830. The
paint was in fairly rough condition here (peeling) as it gets
afternoon direct sun. We
had the wall scraped thoroughly, then primed and painted the wall.
Much to my dismay, the new paint is already peeling rather
dramatically on this wall. Do
you have an idea of why this particular wall doesn't seem to hold
paint? – Mike in
Vermont
The cause of
your peeling paint appears to be heavy paint buildup, exacerbated
by moisture. It looks like your fine old clapboards are not the
cause of the problem. The main source of moisture is probably
rain, seeping into the cracks in the paint film and at joints
between wooden parts. Moisture from inside the wall or house may
also contribute.
The only low-cost solution is spot paint maintenance. For a more
costly long-term solution there are two approaches:
complete paint removal down to bare wood then starting over
with re-painting; or
replacement of the woodwork.
Spot Paint Maintenance Program
This treatment "goes with the flow" in that the
paint is allowed to peel off, mostly at its own rate. Full coating
is not done since this would further shorten the cycle of coating
and peeling. Appearance will be "variable," but is not
usually consider "shabby". Every three to five years the
paint surfaces are cleaned, loose paint is knocked off and the
bare wood in these spots is primed and painted. There is no
attempt to feather the thick edge of heavy paint buildup since it
will do little to extend the life of the work. Relatively weak
"oil-based" primers and paints are used. Matching the
color and sheen of the surrounding paint is important. This is a
relatively low cost treatment, but it must be repeated for as long
as there is heavy paint buildup that is peeling off. Lead
containing waste material does not usually require costly special
handling and disposal since relatively smaller amounts are
generated, although you will still want to handle and dispose of
them responsibly. The continuing cost of this treatment over the
long-term might be higher than complete removal. Typical costs are
$5. - $11./sq.ft. with only 10-30% of the exterior needing
treatment.
Complete Paint Removal and Recoating
All paint is removed down to bare wood. The surface is
prepared and oiled if needed, primed, and painted with two top
coats. "Oil-based primer is used and top coats are so-called
"latex" with 100% acrylic binders. This is a very high
cost treatment, but is only done once. Since it removes the basic
cause of the problem (excessive paint buildup) the cost of
continuing maintenance is much lower than the spot paint
maintenance approach. Typical costs are $16. - $26./sq.ft.. This
includes access, removal, consolidating oil, primer, 2 top coats
paint, but does not include the cost of disposal of special or
hazardous lead paint waste. In recent years the rising costs of
safely removing and disposing of lead paint has made complete
removal a choice of last resort. Usually Steam Paint Removal or
chemical methods are used since grinding the paint off with
sanders or “shavers” creates large volumes of lead dust, and
dry-heat removal methods are a fire risk. We often limit complete
paint removal to areas with difficult access such as towers where
long-term performance is needed and on areas where appearance is
important such as at front doorways. And then we do spot paint
maintenance on the rest of the place.
Clapboard Replacement
If you go this route, use vertical-grain radial-sawn clapboards,
which hold paint better than ordinary flat-sawn clapboards. The
difficulty with replacing the woodwork is that you will have to
pay top dollar for the best quality clapboards and knowledgeable
carpenters to install them. Even then you may not get clapboards
as good as the ones you have now. Old wood is often much better
quality and more durable than new wood. Saving your old clapboards
by doing spot paint maintenance or complete paint removal could
cost less in the long run.
Clapboard
Suppliers:
Ward Clapboard Mill
Moretown
,
Vermont
· 802-496-3581
Patten,
Maine
· 207-528-2933
www.wardclapboard.com
Stephen Jeffery
269 France Road
Barrington
,
NH
03825
603 664-9002
sjeffery.nh.ultranet@rcn.com
Learn more
about clapboards and paint at John’s three-day workshops on
exterior woodwork repairs and painting
. Details at: www.HistoricHomeWorks.com
Contact
Leeke directly for answers to your questions and more information
on techniques for restoring and maintaining your historic
building. Write to John Leeke, Preservation Consultant at
26 Higgins St.
,
Portland
ME
04103
, 207 773-2306; or by E-mail at johnleeke@HistoricHomeWorks.com
or visit his Internet Web Site at www.HistoricHomeWorks.com.
Live Video Conferences &
Replays:
http://historichomeworks.com/hhw/conf/vidconf.htm
Historic HomeWorks Forum:
http://historichomeworks.com/forum/
© John Leeke
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