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Durable Exteriors
ABOVE: The
yellow-mesh rain
screen under the
cedar shingles at
the 2018
Jamestown Net-
Zero House
provides an easy
way for water
to escape.
BELOW, FAR LEFT:
The 2017 Newton
GenerationNEXT
House is covered
with lap siding and
shingles made of
low-maintenance
fi ber cement.
LEFT: At the 2017
TOH Idea House,
the exterior trim
around the doors
and windows, and
over the beams
and columns, may
look like painted
wood, but it’s
actually rot-proof
cellular PVC.
Drainage planes The airspace
established by the dimples on Dorken’s
below-grade foundation membrane
halts the migration of water from soil
into concrete. Delta-MS; dorken.com
No-leak fl ashing Rubbery
membranes—both stick-in-place
sheets like Ice & Water Shield and
brush-on liquids—form a barrier
that keeps water off roof sheathing
and the framing around windows
and doors. Ice & Water Shield;
gcpat.com
Fiber-cement siding Pioneered
by James Hardie, this mix of wood pulp,
sand, and cement resembles wood
siding but doesn’t have wood’s high
cost, tendency to decay, or need for
frequent repainting. HardiePlank
lap siding; jameshardie.com
Rain screens When installed over
wall sheathing, a mesh like Slicker HP
creates a naturally ventilated air gap
that allows wood siding—both lap and
shingles—to dry out after it gets wet.
Slicker HP; benjaminobdyke.com
Rot-free wood Decking that can
withstand the elements doesn’t have to
be soaked in toxic metals, made of
plastic, or grown in a rain forest.
Thermory’s thermally modifi ed white
ash—from U.S. and European forests—
is cooked until it’s unpalatable to
insects and rot fungi, a process that also
makes the boards more stable than
untreated ones. Benchmark White
Ash Decking; thermoryusa.com
Forever trim Cellular PVC, brought
to the U.S. market by AZEK, looks and
cuts like painted pine, but doesn’t
decay, warp, or get chewed up by
insects. And it’s not just for trim; the
material is also fashioned into
handrails, moldings, fences, and
pergolas.
AZEK ; azekexteriors.com
The key to a low-maintenance,
long-lasting exterior is to use
building materials that can
withstand the elements, and to
install them in a way that always
allows moisture a means of
escape. Some products sit unseen
beneath siding or soil. The more
visible, man-made trim and
siding offer unmatched durability
without compromising aesthetics.
“ I have cellular PVC trim
and fi ber-cement siding
on my Victorian-era
house, and most people
can’t tell it isn’t wood.”
—TOM SILVA
40 YEARS SEPTEMBER/OCTOBER 2019 THISOLDHOUSE.COM 69