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Building Science |
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GOAL: Perfecting the "Building Envelope":
-the "building envelope is defined as: a total system of
construction materials and design components that
control the temperature, movement of air and moisture
both in and out of the building." |
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Challenge: "The Stack Effect"
- Sometimes called the “chimney effect”—is a problem
most homes have. Basic science tells us that warm
air will rise and cooler air will sink. In summer,
your attic temperature routinely can hit 140
degrees. This warm air builds up and pushes all of
your conditioned air down through the home and out
through the floor of the lowest level. In winter,
all of the heated conditioned air generated is
slowly rising through each level of the home via
ductwork, plumbing penetrations, recessed lighting,
poorly insulated ceilings, etc. and then can easily
escape through openings in your attic, ridge vents
and soffits. Of course the air in the house below
must be replaced, and in older homes the leakage can
be as high as two air exchanges per hour. This is
the primary contributor to your energy loses, and
can affect your comfort levels (bodily and
financial). |
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Problems Associated With "The Stack Effect" |
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Heating and cooling systems work much harder than
they need to in order to maintain the desired level
of comfort (thus leading to excessive utility bills)
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High temperatures in attic spaces can lead to
condensation/moisture build up on equipment
(reducing lifespan on that equipment)
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Ductwork in the attic will experience excessive
energy losses due to the high temperature
environment
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In homes with a crawl-space, up to 50% of your air
on the first level of your home comes from the
crawlspace—often laden with high humidity, mold and
bacteria.
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SOLUTION: "Attic & Crawl Space Encapsulation" |
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Attic Encapsulation - |
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1. We apply Open-cell spray polyurethane foam
directly to the underside of the roof decking, from
the peak of the roof all the way to the soffits. In
addition, we unplug all attic fans and seal around
them, seal all vents, extend any necessary plumbing
stacks to the top of the attic (for required
ventilation) creating an "Attic Encapsulation". We
now prevent the heat (that would normally rise up
through the ceiling and go out the roof vents) from
escaping thus backfilling the home with precious
heat that previously would have been lost. Even in a
relatively well-sealed home about half of the air
escapes each hour out of the upper levels. The
problem is endemic because the standard design of
homes is to vent air out the top. |
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This creates suction on the lower levels, pulling
air from the lower part of your house into the attic
and out of the house. In the summer time, (after
attic encapsulation) the attic space will now be no
more than 10 - 13 degrees difference from the floor
below it. The Attic space now becomes a
semi-conditioned, usable space. This step is perhaps
the single biggest contributor to lower your utility
bills! |
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Crawl Space - |
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2.We apply Closed-cell spray foam directly to the
ceiling of the crawl space. By sealing every crack,
nook, crevice, we are stopping contaminated air from
moving up into the home, preventing ground vapor,
mold, humidity, bacteria and gases from being drawn
up through the floor into the living space. The
closed cell foam dramatically improves the
structural integrity (up to 300%) of the floor
joists and eliminates the creaking of the floor that
you find in older homes and is impervious to
moisture while like at the same time allowing the
home to breath (similar to GORTEX). |
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In the summertime, we now prevent the air
conditioning that normally is being pushed down
through the home out through the crawl
space/basement, from escaping. Building scientists
say that in homes with a crawl-space, up to 50% of
your air on the first level of your home comes from
the crawlspace— By sealing the attic and crawl space
we now have enhanced the building envelope |
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