Project
2.1 - Attic Ventilation
Objective
To compare performance of different passive non-mechanical methods for ventilating
attics in HfH and manufactured housing to evaluate the relative effectiveness
and costs of the methods in reducing space conditioning loads and energy use.
Examples of the methods to be examined include the following:
- Sealed attic construction
with no venting
- Ridge vents with soffit
vents
- Radiant barrier systems
- White reflective roofs
- Enhanced attic ventilation
and roof tiles
Prior Research
Attics in houses in California's Central Valley can be brutally hot during a
summer day. When walls and ceilings absorb heat, attic temperatures can climb
to over 150 degrees. The high heat conditions in attics can affect air conditioning
loads in two ways: through ceiling heat transfer from the attic to interior
space and through heat transfer to ducts in the attic space.
Tasks
- Review prior research
- Prepare monitoring plan
- Select sites and construct
eight homes
- Implement ventilation
methods
- Instrument eight homes
- Data collection, modeling
and ventilation effectiveness
Projected Outcomes
- Quantified comparison
of costs and effectiveness of different methods of attic ventilation when
applied to houses built by HfH affiliates and manufactured housing builders.
Costs will specify installation labor time and rates (when applicable), and
retail and wholesale equipment and materials costs.
- Quantitative results
expected from this project are electricity savings of 70 kWh per household.
- The penetration rates
for the HfH ventilation systems recommended as a result of this work are 7
percent in the first year and 35 percent in the fifth year. For manufactured
housing, the penetration rates are 5 percent in the first year and 25 percent
in the fifth year.
Please visit the Project
News and Public Documents page to view
updates for this task, and current research activities.
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