Page 27 - The Homeowner's Handbook 2017

Exteriors / Roofing / Structure / Insulation / IAQ / Windows & Doors / Heating & Cooling / Lighting / Appliances / Plumbing / Finishes / Cabinets & Tops / Alternative Energy

Cladding Considerations Some claddings,

E such as stucco and
XTRA-THICK LAYERS of exterior insulation can greatly
adhered stone
improve the energy performance of homes, but installation
veneer, may
require additional
requires some special techniques.
support between
For thinner insulation, the cladding can often be attached directly
the structural
through the rigid insulation back to the structure. The practical limit furring strips to
of this approach is around 1-½” of rigid insulation, due to the limited facilitate the
installation. Wood
fastener lengths for many pneumatic nail guns. shingles require a
For thicker insulation, vertical wood furring strips can provide continuous nail
a cladding attachment location. This approach also provides a base, which is best
drainage and ventilation gap behind the cladding, which helps provided by
installing another
manage water. To adequately support the cladding, the furring strips CREDIT: BUILDING SCIENCE CORPORATION layer of structural
should be attached back to the structure using #10 or larger wood sheathing directly
screws that are sized to maintain a 1-¼” minimum embedment into over the insulation
the structural framing. in place of wood
furring strips.

CELLULOSE
Paper Trail Fixing a Hole
Cellulose has a good green story to tell, especially from the
manufacturing side. It’s made primarily with recycled paper, typically with Attic Caps
newspapers, and most brands are treated with boric acid as a fire
retardant. Research on the health effects of boric acid suggest that
it is a minor irritant in small doses. Cellulose can be installed wet
or dry. If installed wet, it should be allowed to dry properly before
covering with drywall (typically less than 48 hours). The insulating
value of cellulose is about the same as blown fiber glass (roughly
R-3.7 per inch).

MINERAL WOOL
Nothing to Burn
Although mineral wool looks like fiberglass, it’s made from basalt CREDIT: OWENS CORNING
rock and slag, not glass. The resulting product, either batts or loose

Easy-to-Use Options. Using a reflective material to cover
stair openings, the Attic Stairways Insulator by Owens
Corning helps to reduce seasonal heat loss and gain.
While no one seems to have exact figures, third-party testing
suggests that some brands cut attic air infiltration by 70 percent.
The ready-made systems, such as Owens Corning’s foil-covered
Attic Stairway Insulator (R-10; $54), are almost effortless to install.
Systems like those offered by Owens Corning work well in attics,
where traffic is infrequent. In homes where the homeowner
trucks in and out of the attic every day, however, other products
offer more flexibility. For example, a rigid foam system such as
the Energy Guardian (R-38; $185) has a removable foam top.
The lightweight Attic Tent (R-3.2; $200) seals tightly with zippers.
So, how much energy do attic caps really save? Attic Tent
Bayseal Insulation estimates about a 20 percent annual heating/cooling reduction.
Covestro’s Bayseal insulation provides a high R-value and reduces air
intrusion, accumulation, radiative heat transfer and air movement. A The products also reduce unwanted air infiltration, offering other
spray polyurethane foam expands, filling cracks, crevices and voids “green” benefits, such as keeping dust and pollutants out of living
to create a seamless air barrier system that provides high building areas and reducing drafts.
envelope performance. http://bit.ly/2dM2Rty

www.greenbuildermedia.com The Homeowner’s Handbook 2017 GREEN BUILDER 25

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