Hot attic

[mmojbafan]

I inspected a house yesterday, 2000 construction mid size home, no major problem or anything, only the attic was extremly hot (55 C) outside temperature about 28, shingles are black, One Maxxima 301 at the correct location and all the soffits are open. About 8 inches of cellulose insulation with the proper vapor barrior.
Everything seemed to be normal...but why the attic was soo hot..the only thing I could think of is that perhaps the vent is not strong enough for proper ventilation..anyother thoughts??
Ohh..by the way, the house is located in montreal canada..thanx

[James H. Bushart]

Ventilation is to remove moisture. If there were no signs of moisture, there is no need to recommend additional ventilation, IMO.

[Tom Leahy]

http://www.nachi.org/forum/f18/attic...06/index3.html

[David A. Andersen]

Originally Posted by jbushart

Ventilation is to remove moisture. If there were no signs of moisture, there is no need to recommend additional ventilation, IMO.

How do you figure?

[James H. Bushart]

Originally Posted by dandersen

How do you figure?

If your asking from an energy conservation standpoint, "attic ventilation is less important than roof reflectance, radiant barriers and attic insulation in retarding solar heat migrating through the roof and attic."*

Removing solar heat and humidity is a plus but in hot and dry climates, some codes allow, when properly sealed against any moisture entry, for no ventilation at all. In wetter areas like my state, we need the ventilation in the summer to remove the heat and the humidity.

During the heating season especially, attic ventilation serves to allow the moisture that is generated from within the home (perspiration, respiration, condensation, showers, cooking, etc) to have a way out after it has been drawn in to the attic.

I could be wrong, but I am considering that the lack of a substantial heating season and relative moisture buildup is why the codes in these hot, dry areas do not require ventilation.

*(Residential Energy, J. Krigger & C. Dorsi, 5th Edition, 2009)

[Larry J. Michael]

Great info James

[Brian E. Kelly]

Originally Posted by jbushart

If your asking from an energy conservation standpoint, "attic ventilation is less important than roof reflectance, radiant barriers and attic insulation in retarding solar heat migrating through the roof and attic."*

Removing solar heat and humidity is a plus but in hot and dry climates, some codes allow, when properly sealed against any moisture entry, for no ventilation at all. In wetter areas like my state, we need the ventilation in the summer to remove the heat and the humidity.

During the heating season especially, attic ventilation serves to allow the moisture that is generated from within the home (perspiration, respiration, condensation, showers, cooking, etc) to have a way out after it has been drawn in to the attic.

I could be wrong, but I am considering that the lack of a substantial heating season and relative moisture buildup is why the codes in these hot, dry areas do not require ventilation.

*(Residential Energy, J. Krigger & C. Dorsi, 5th Edition, 2009)

I still see Bathroom vent fans into attics here in older homes....years and years of venting and no visible adverse effects whatsoever.

[Marcel R. Cyr]

Brian, that is because it is so stinking hot and dry over there and the tumble weeds in the attics are absorbing all the moisture.

[James E. Braun, CMI]

I inspected a year old condo, Monday, when I removed the attic access cover my glasses fogged up immediately. The builder told the owner that he has no idea why there is mold on the ceilings.