Extremely High Attic Temperatures
Recent client of a BP installer has a complaint that her “attic temps are well over 100F” in Summertime after spray foaming roof deck 3 yrs ago.
Very typical 22 x 38 attic layout, 9 or 10 pitch roof over a 150 y/o 2 story gable end New Englander. The typical old New England house. Southern New Hampshire location.
Attic space is intended to be a fully insulated space but is not purposely conditioned w/ heat or cooling. No venting.
5-6″ closed cell spray foam, on roof deck, 3-4″ on gable triangles.
The previous gable end attic vents were spray foamed over.
1 masonry chimney through the attic and roof but it doesn’t run in Summer, is just a space heating boiler, DHW is electric.
No gable end glazing nor Skylights.
Not much shade on the roof, it’s Summer.
I think the summertime attic temps s/b within about 15F, give or take, of the 2nd floor rooms.
We just visited for the 1st time to take a look, but it’s April, ext. temps were 55F, the 2nd floor bedroom and hall temps about 70F and 5 points measured in the attic were all about 71F. All seemed fine at the visit. Client insists it is impossible to enter during Summer and she is wary is storage up there.
We’ll be returning 1st of June to see what sunnier days and higher ext. temps may do.
1) Am I right expecting the attic space should be pretty close to the 2nd floor space and 2) if it truly is over 100F in the attic, any suggestions about the likely causes?
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