Attic Fan

NoBozo · 04-12-2011, 10:45 AM

We have a typical 24'x44' raised ranch with a "Hip Roof" with two 8'' box vents ..one on each end and no soffit or ridge vents... = Hot attic.

We also had a remote reading thermometer in the attic before and after we had a Master Flow attic fan installed. Before the fan, the temp in the attic in the afternoon would typically be 145+ degrees on sunny days in August. Without the forced ventilation that temp would pretty much remain until 5:00 AM the next morning. It was like a Hot Blanket above all the rooms in the house.

After we added the fan AND 16 soffit vents under the wide roof overhangs, the temp rarely goes over 107 degrees on the hottest days. The fan was less than $100 at Home Depot. We had the fan installed when the roof was re-shingled in 2003. The fan has a thermostat in the attic which turns the fan on at about 90 degrees and there is a manual shutoff switch in the utility room.

BTW: The old 8" box vents were Eliminated and we Did Not have "Ridge Vents" installed as they would interfere with the airflow with the new fan. NB

Hip Roof: http://en.wikipedia.org/wiki/Hip_roof

Master Flow: http://www.gaf.com/Roofing/Residenti...entilator.aspx

chipj29 · 04-12-2011, 11:37 AM

Thanks jmen and campguy.
I have ridge vents running the length of the roof line, which is about 50'. There are gable vents on each end, and another gable vent over the overhang.
I think the prob with the gable vents is that they are very small. Just some slits in the aluminum siding. I have been wanting to install some bigger gable vents, now that I know it will help, I have the motivation!

Thanks again!

04-12-2011, 11:37 AM	#2
chipj29 Senior Member Join Date: Apr 2004 Location: Bow Posts: 1,874 Thanks: 521 Thanked 308 Times in 162 Posts	Thanks jmen and campguy. I have ridge vents running the length of the roof line, which is about 50'. There are gable vents on each end, and another gable vent over the overhang. I think the prob with the gable vents is that they are very small. Just some slits in the aluminum siding. I have been wanting to install some bigger gable vents, now that I know it will help, I have the motivation! Thanks again! __________________ Getting ready for winter!

04-12-2011, 10:45 AM	#1
NoBozo Senior Member Join Date: Jun 2008 Location: Portsmouth. RI Posts: 2,231 Thanks: 400 Thanked 460 Times in 308 Posts	We have a typical 24'x44' raised ranch with a "Hip Roof" with two 8'' box vents ..one on each end and no soffit or ridge vents... = Hot attic. We also had a remote reading thermometer in the attic before and after we had a Master Flow attic fan installed. Before the fan, the temp in the attic in the afternoon would typically be 145+ degrees on sunny days in August. Without the forced ventilation that temp would pretty much remain until 5:00 AM the next morning. It was like a Hot Blanket above all the rooms in the house. After we added the fan AND 16 soffit vents under the wide roof overhangs, the temp rarely goes over 107 degrees on the hottest days. The fan was less than $100 at Home Depot. We had the fan installed when the roof was re-shingled in 2003. The fan has a thermostat in the attic which turns the fan on at about 90 degrees and there is a manual shutoff switch in the utility room. BTW: The old 8" box vents were Eliminated and we Did Not have "Ridge Vents" installed as they would interfere with the airflow with the new fan. NB Hip Roof: http://en.wikipedia.org/wiki/Hip_roof Master Flow: http://www.gaf.com/Roofing/Residenti...entilator.aspx