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Michael Weber
04-24-2017, 3:01 PM
Want to lower my summer attic temps. Anyone have experience with these? Do these thing actually move the amount of air they claim? Thinking of installing one near the peak of my pyramid shaped roof. Have lots of soffit vents to supply make up air.

keith wootton
04-24-2017, 3:54 PM
made a big difference in my shop. one single solar vent in pyramid shaped roof of my 400 sqft shop. my roofer was none too happy to come back and add it after i wasnt happy with ridge vents that he thought were going to do the job. still does get warm in attic, but nothing like it did before. i live where 100+ is common and no shade over shop.

George Bokros
04-24-2017, 5:52 PM
Have lots of ridge vents to supply make up air.

You really need vents in the overhang to supply the intake air. IMO a ridge vent is too high.

Lee Schierer
04-24-2017, 6:30 PM
You really need vents in the overhang to supply the intake air. IMO a ridge vent is too high.

I was going to say the same thing. Many homes don't have adequate air inlet at the lower edges of the roof.

Malcolm McLeod
04-24-2017, 6:36 PM
I was going to say the same thing. Many homes don't have adequate air inlet at the lower edges of the roof.

Add another voice to the chorus. Ridge vents allow hot to rise and escape. They are not setup to pull air in.

Also, if there are ridge vents, there should be soffit vents. One is useless without the other.

Mel Fulks
04-24-2017, 7:27 PM
I see it differently ,pulling in a lot of air from a full sun exposure side with a dark color roof just made a lot of fresh hot air.
I loaded up on insulation and got rid of soffit vents. Now use attic gable fan ,much better results.

George Bokros
04-24-2017, 7:31 PM
I see it differently ,pulling in a lot of air from a full sun exposure side with a dark color roof just made a lot of fresh hot air.
I loaded up on insulation and got rid of soffit vents. Now use attic gable fan ,much better results.

Where do to you get intake air if there are no soffit vents? With no intake air your create a vacuum.

Mel Fulks
04-24-2017, 7:36 PM
Have louver gable vents on both ends.

James Baker SD
04-24-2017, 8:56 PM
Our house has soffit vents in a 4' overhang. Unfortunately the previous owner covered them all with insulation and there is no air flow through them. The roof gets so close to the soffit vents that reaching in to uncover them from inside the attic is essentially impossible until the next time I get a new roof.

I bought 2 AC fans with 1/8 HP motors. On one fan I reversed the blade and rewired the motor to rotate in the opposite direction, turning it into a sucking fan. The sucking fan is installed on the north end of the house near the interior ceiling (fortunately not visible from the ground due to the overhang) and the blowing fan on the south end of the house near the roof hip.

They are thermostatically controlled, so I ran enough wires between them that both are controlled by one thermostat and both on the same circuit breaker in the panel. So either they are both on or both off. I installed the single thermostat about 18" or 2' from the roof so it would not measure just the trapped heat under the hip.

Occasionally they run quite late into the night and it bothers my wife's sensitive ears. So I also added a wall switch in the master bedroom which will force them off. She has used the switch multiple times.

I am pretty happy with the result. Temp measured halfway between the fans dropped from 130F to 100F (August measurement).

Mel Fulks
04-24-2017, 9:09 PM
James your experience sounds a lot like mine. If it's not easy to take out that insulation blocking the vents ,then it wasn't easy to put it in. But I'm betting it made an improvement.

Michael Weber
04-24-2017, 10:41 PM
Okay, I did a boo-boo. I meant to say soffit vents and not ridge vents. I have a Lot of insulation and the soffits are clear. I rejected ridgevents as outlets due to the roofs configuration. Like James I have 4 foot overhangs and his idea is appealing but wanted to do as low an energy solution as I could. Was worried the air movement claims of the solar powered vents are unrealistic based on the wattage specifications. If Keith's experience is typical, I'll try it. Anyone else happy with their results of a solar powered vent? Sorry about the confusion caused by my mistaken description.

Jim Andrew
04-27-2017, 11:21 AM
If insulation is blocking your soffit vents, the lumberyards offer a simple part designed to open up the air to the attic. It is just a sort of corrugated piece of thin foam that you slide in between the roof sheathing and the insulation. You can staple the top corners to hold it in place.

Lee Schierer
04-27-2017, 5:50 PM
If insulation is blocking your soffit vents, the lumberyards offer a simple part designed to open up the air to the attic. It is just a sort of corrugated piece of thin foam that you slide in between the roof sheathing and the insulation. You can staple the top corners to hold it in place.

When I added insulation to our attic, I noticed that there were some rafter cavities blocked by the existing insulation and that the new insulation would add to that problem. The foam devices sold t keep airways open don't have enough strength to push away the insulation blocking the vent, so I purchased some 4" SD pipe from the local big box store and cut it into 2 foot lengths. These were strong enough and long enough to get past the insulation blockage and allow air flow. I placed one pipe in each rafter space and have no more air flow problems. On a warm day you can actually feel the cool air flow through those pipes.

Allowing attic air flow in the winter in northern climes also prevents or at least significantly reduces icicles and ice dams during the winter months. Deep snow can defeat ridge vents.