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Cooling Energy Measurements of Houses with Attics Containing Radiant Barriers
Abstract
Tests were conducted by Oak Ridge
National Laboratory (ORNL) to determine
the magnitude of the energy savings
brought about by installing radiant
barriers in the attics of single-family
houses. The radiant barrier used for
this test was a product with two
reflective aluminum surfaces on a kraft
paper base. The radiant barrier has the
potential to reduce the radiant heat
transfer component impinging on the
fiberglass attic insulation. Working as
a system in conjunction with an air
space, the radiant barrier could
theoretically block up to 95% of far-infrared
radiation heat transfer.
The experiment was conducted in three
unoccupied research houses that are
operated by ORNL. One house was used as
the control house (no barrier was
installed), while the other two were used
to test the two different methods for
installing the radiant barriers. In one
house, the barrier was laid on top of the
attic fiberglass batt insulation, and in
the other house, the barrier was attached
to the underside of the roof trusses.
The attics of all three houses were
insulated with kraft paper faced nominal
R-19 fiberglass batt insulation.
The results showed a savings in the
cooling loads of 21% when the radiant
barrier was laid on top of the attic
fiberglass insulation and 13% with the
radiant barrier attached to the underside
of the roof trusses. The savings in
electrical consumption was 17% and 9%,
respectively. The electrical consumption
data and the cooling load data indicated
that the most effective way of installing
the foil was to lay it on top of the
fiberglass batt insulation. The radiant
barriers reduced the measured peak
ceiling heat fluxes by 39% for the case
where the barrier was laid on top of the
attic fiberglass insulation. The radiant
barrier reduced the integrated heat flows
from the attic to house by approximately
30-35% over a 7-day time period.
Citation
Levins, W. P.; Karnitz, M. A.; Knight, D. K. (1986). Cooling Energy Measurements of Houses with Attics Containing Radiant Barriers. Energy Systems Laboratory (http://esl.tamu.edu); Texas A&M University (http://www.tamu.edu). Available electronically from https : / /hdl .handle .net /1969 .1 /6871.