Has anyone installed a garage attic fan?

[tallhair]

I'm going to have my roof replaced soon along with some other work and I'm thinking of installing one of these to keep the garage and attic cooler.

Premise is it sucks hot air out of the garage and fresh air in through vents installed in the garage door and forces the hot air in the attic out of the ridge, soffit, etc vents. Benefit is supposed to be the attic is cooler which helps keep the garage cool and sucks hot air out of the garage and sucks in cooler outside air, and provides ventilation and moving air. Supposedly costs < $20 a year to operate and cools the garage by 20 degrees, and attic by 30 or 40 degrees.

The house/garage is 10 years old. Both have plastered drywall finished walls with insulation in the walls and ceiling. When it's below freezing outside it's comfortable for a short time in the garage with light jacket or sweater in the winter time .. so winter is not really a problem. However it faces West and is hot as hell in the summer time even when we keep the door down in the afternoon when the sun is blazing straight at it and I don't pull the cars in after driving them home after work etc. The garage is attached to the house and has a full ridge vent and metal ventilated soffit vents and a decorative but functional vent on the top front face that's about 1 1/2 ft in diameter. It also has an insulated garage door. I'm not trying to get it down to 70 but i'd like to have it at around 85 or below with some air movement when it's 95+ outside. At present it's at least as hot in the garage as it is outside if not hotter.

I'm hoping someone has done this or knows something about if it will work or not.

Thoughts? Opinions? Suggestions? Alternatives? Commentary?

http://www.coolmygarage.com/shop/gf-14-garage-ventilation-fan-attic-cooler/#!prettyPhoto

VIDEO HERE .. forward to 2:40 minutes .. the other thing may be worthwhile too or just snake oil :icon_smurfin:

[video=youtube_share;SzOmlw3LD8Y]http://youtu.be/SzOmlw3LD8Y?t=2m28s[/video]

 

[Cranky]

My shop is 52 feet long and have 3 turbine vents on top. Attic is open and my shop is never 20 degrees hotter than the outside temp....even when it's been closed up all day.

 

[tallhair]

Not saying the garage is 20 degrees hotter. The company claims it's supposed to cool the garage by up to 20 degrees. My garage is hotter than the outside though and has no air movement with the door down .. not really any with the garage door open either. However if I open the garage door and the man door it's cooler with air movement, but in the afternoon the sign shines straight in and heats up the concrete

 

[hunt2elk]

They were a lot more popular in my area 35 years ago. I'd say do a decent job on the ridge and soffit venting - blow in a good amount of insulation, and call it a day. They aren't worth the cost in my opinion.

 

[tallhair]

Post edited to add info .. house / garage has wall / ceiling insulation and ridge / soffit vents. Garage is still hotter than outside. It faces West and has minimal air movement and is hot as hell or at least hotter than outside where the air is at least fresh and moving.

 

[62MAX]

From Lowe's cheap and works great !

http://www.lowes.com/pd_85947-228-RV26ML_0__?productId=1102561&Ntt=attic+exhaust+fan

 

[hunt2elk]

From Lowe's cheap and works great !

http://www.lowes.com/pd_85947-228-RV26ML_0__?productId=1102561&Ntt=attic+exhaust+fan

This one would be far cheaper to experiment with - you could even add 2.

 

[Dako]

I bought and installed a couple 52" ceiling fans Lowes had on clearance for $29 a piece. They do wonders making it bearable. For the real hot days, I have one of those roll around A/C units that draws and dumps out air through flexible tubes to the outside. They can be set up to do this via a window or holes punched through a wall (comes with caps to close them off when not in use). Even with my unit being slightly undersized for the garge square footage, it does a good job of keeping things cool with the doors closed.

 

[tallhair]

Thanks Dako .. those A/C units you are talking about are actually very effective. We had some when i was in England since we had no plumbed in A/C in our building. They were very effective. Good idea.

 

[pushrod]

Try installing gable vents first. The soffitt vent provides the fresh( cool) air for the
attic and is pulled in as the hot air exits through the ridge vent. When installing a power vent you have to have proper cfm for the hot air to exit, thus the need for a
gable vent, or other means of handling the air flow.

 

[tallhair]

Thanks pushrod .. appreciate the feedback of everyone

 

[2059]

When I built My previous house house ~10 years ago I installed power vents in the gable ends of the attic, it was a metal roof and i didn't want a ridge vent. anyway I set the thermostats at 95 degrees when they would kick on . I would say they helped keep the main house cooler.

Here's something else you might want to consider; in our part of the country humidity is equally an issue along with temperature. In my shop, 30X60, I run a free standing small dehumidifier that has a drain hose plumbed through the wall. During the summer, I let it run and even though the shop is almost 80 degrees the humidity is about 15% and its very comfortable. even when it's 95 and 80% humidity outside (like it was yesterday). the key is keeping the doors shut as much as possible.

 

[Richard Cranium]

I run a dehumidifier all year long but in the summer it does generate quite a bit of heat, but in the winter, it does help with keeping the garage warm. No matter, it's a big plus.

 

[tallhair]

Try installing gable vents first. The soffitt vent provides the fresh( cool) air for the attic and is pulled in as the hot air exits through the ridge vent. When installing a power vent you have to have proper cfm for the hot air to exit, thus the need for a gable vent, or other means of handling the air flow.

I don't understand what you are getting at pushrod. I have one gable vent on the face of the garage. I'm looking at a vent that is supposed to force garage air into the attic which is supposed to force the hotter attic air out of the ridge vent. Will adding the fan on the garage ceiling not force the air out the ridge vent?

When I built My previous house house ~10 years ago I installed power vents in the gable ends of the attic, it was a metal roof and i didn't want a ridge vent. anyway I set the thermostats at 95 degrees when they would kick on . I would say they helped keep the main house cooler.

Here's something else you might want to consider; in our part of the country humidity is equally an issue along with temperature. In my shop, 30X60, I run a free standing small dehumidifier that has a drain hose plumbed through the wall. During the summer, I let it run and even though the shop is almost 80 degrees the humidity is about 15% and its very comfortable. even when it's 95 and 80% humidity outside (like it was yesterday). the key is keeping the doors shut as much as possible.

My garage is pretty humid .. I'll get a guage though to measure it and see what it is compared to outside. I hadn't thought of the humidity yet .. thanks

I run a dehumidifier all year long but in the summer it does generate quite a bit of heat, but in the winter, it does help with keeping the garage warm. No matter, it's a big plus.

hmmm I wonder if the attic fan (same principal as a whole house fan) will work against the dehumidifier by moving air faster than the dehumidifier can work its magic

 

[Mooky]

is your garage classic white or a dark color?....I have a cut stone face on my house and garage and had a dark color roll door and no venting...added roof/can vent and soffit vents along the eve's and installed a bright white insulated roll door and blew in 9 inches of attic cellulose insulation and is a tad cooler than the outside temp...I have found like others have said that the humidity is the killer on the hot days....I also run a small stand alone dehumidifier and a osculating fan .... remember to keep a mini-fridge stocked full of beer and all will be well ;) gl

 

[2059]

Tallhair, you want to think about this as two separate areas. The attic as one and the living area (or in your case the garage) as two. as you know the idea behind ventilating the attic is two-fold; for the summer, via natural convection or fan forced, the hotter air will move out of the attic via soffit vents around the eaves of the house/garage with intake of "cooler" air thus exiting "hot" air through the higher gable vent or ridge vent, In the winter, you need air moving through the attic area in order to avoid moisture/condensation in the attic because of the temperature differential from inside the living area to the cooler attic area. No matter the method (natural convection or fan forced) , this is an isolated/sealed area.

The whole house fan will pull the air from the exterior, through the living quarters, to the attic and force the hot air out of the attic through the gable vents and/or ridge vent. here's the problem, as you pointed out; humidity. with whole house fans in our part of the country you will pull in humidity faster than any equipment can remove it. I used a whole house fan when I lived in California and it worked very well to cool the house through out the night, then closed up the house and turned it off during the day. Because the humidity was so low there it worked well and my AC would not come on until mid afternoon.

I think you'll be amazed at how comfortable you garage will be if you make sure your attic above the garage is properly vented and you're able to get that humidity down around 15%.

Good luck!!

 

[tallhair]

is your garage classic white or a dark color?....I have a cut stone face on my house and garage and had a dark color roll door and no venting...added roof/can vent and soffit vents along the eve's and installed a bright white insulated roll door and blew in 9 inches of attic cellulose insulation and is a tad cooler than the outside temp...I have found like others have said that the humidity is the killer on the hot days....I also run a small stand alone dehumidifier and a osculating fan .... remember to keep a mini-fridge stocked full of beer and all will be well ;) gl

The garage and house has rose colored brick on front and grey vinyl siding on the rest of the exterior. The garage has only 2 outside walls .. front west side is brick south side vinyl. The garage is finished with insulation in walls and on the ceiling. The attic is open to the rest of the first floor attic and has soffit and ridge vents. The garage door is insulated and is cream color.

I just put an humidity gauge out there and it's 80% right now .. very mild day and only about 78 outside / in the garage right now .. I'll consider the dehumidifier if I don't go with the attic fan as I would imagine their air wouldn't be in the garage long enough to get dehumidified if there air was flowing in and up into the attic, but adding humidity to the attic is a concern ??? Still researching and wondering.

thanks for the suggestions and yeah I should get me a garage fridge

- - - Updated - - -

Tallhair, you want to think about this as two separate areas. The attic as one and the living area (or in your case the garage) as two. as you know the idea behind ventilating the attic is two-fold; for the summer, via natural convection or fan forced, the hotter air will move out of the attic via soffit vents around the eaves of the house/garage with intake of "cooler" air thus exiting "hot" air through the higher gable vent or ridge vent, In the winter, you need air moving through the attic area in order to avoid moisture/condensation in the attic because of the temperature differential from inside the living area to the cooler attic area. No matter the method (natural convection or fan forced) , this is an isolated/sealed area.

The whole house fan will pull the air from the exterior, through the living quarters, to the attic and force the hot air out of the attic through the gable vents and/or ridge vent. here's the problem, as you pointed out; humidity. with whole house fans in our part of the country you will pull in humidity faster than any equipment can remove it. I used a whole house fan when I lived in California and it worked very well to cool the house through out the night, then closed up the house and turned it off during the day. Because the humidity was so low there it worked well and my AC would not come on until mid afternoon.

I think you'll be amazed at how comfortable you garage will be if you make sure your attic above the garage is properly vented and you're able to get that humidity down around 15%.

Good luck!!

Thanks for the excellent input .. I just put the humidity gauge out there and it's 80% + and it's a really mild day today. It's mild today and rained quite a bit yesterday so I'll watch the gauge during different weather conditions and temperatures to see what it does

 

[Mooky]

yes, adding humidity to the attic is a bad thing...black mold and other nasties....when the back of your ceiling board or your insulation gets moist it will start to mold and destroy your material and in advance/really bad cases make you sick. your garage set up sounds a lot like mine facing the same direction and yes it would kill a little dehumidifier when pulling external air from the outside into the garage...I use my fan just to move air around the shop....doesn't really change temp but feels more comfortable...I always thought about a wall fan or such but with the cost involved I feel good at the point I am at now...again cool beverages, this is the key. and they taste way better next to the fan watch'n the wife dig for her drinks at the back/bottom of the fridge ;)

 

[tallhair]

Just came in from the garage and 80% humidity and temp is 84 degrees .. outside is 88 according to a digital thermometer .. i'll put that down to thermometer variance. I don't have a humidity gauge outside but the internet says it's 58 percent outside. My humidity gauge could be off, but it's nicer outside than the garage.

I think I'll get a couple new gauges, one for outside and one for inside to see what I'm dealing with

 

[747mopar]

I started running a dehumidifier in my garage last year "wow" what a difference. I used to have problems with surface rust, musky oders, damp floor etc "all gone" probably one of the best investments I've made to the garage. Car stays nice and fresh and it's way more confortable to work.