Is a roof vent an acceptable ventilation source point?
capnkent
| Posted in Mechanicals on
We have a builder who has their fresh air source coming from the low profile roof vent. The ventilation system is an “air cycler” via the gas furnace on the return side with a mechanical motorized damper. The roof is asphalt composition shingles. This seems to be a bad idea but I am not finding code or good data that would either promote or deny this practice. Any suggestions about this subject?
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Replies
Kent,
You don't want a ventilation air inlet to be near hot asphalt shingles. Among the programs that addresses the question is Energy Star Version 3, which requires "Ventilation air inlets > 2 ft. above grade or roof deck in Climate Zones 1-3 or > 4 ft. above grade or roof deck in Climate Zones 4-8."