i have a two car oven.

[georgelowcar]

hello,

i have an detached uninsulated garage (30x30 ft). The garage doors are also metal, uninsulated facing the north. The summers have been oh so brutal. When its hot outside, its unbearable inside the garage. I have had soles of stored shoes melt. Forget about working in the garage.

I'm not asking to cool it to 80 degrees, but i'm hoping i can at least cool it to at least the outside temperate in the shade.

Current solution:
Currently, all i have is a ridge vent and the two opposed windows.

Solution 1:
I'm thinking about putting in one exhaust fan with a vent opening on one end of the garage 'A' frame, and another vent opening on the opposite side. I would then draw air in and exhaust the air.

Solution 2:
Currently, I have two oposed windows. Another option is to put a descent fan on one of these windows and leave the other open to draw air out. Basically, same solution as solution 1, but use existing windows which are already there, but 10ft lower.

Solution 3:
Ceiling fan to draw the air down and then use a fan on the windows to push it out.


I could also leave the garage doors open, but then worry about unwelcome critters.

Do you think creating vents on opposed sides and adding a vent is worth it?. Any idea what type of fan should be used.

thank you
- george

 

[sammm]

Until you get some insulation in there, it's going to be tough to beat the radiant heat, especially if you have standard asphalt shingles.

 

[georgelowcar]

yeah, i figured so much.

Has anyone used one of these GF-16 attic fans to move air out. I'm a bit worried pumping $$$ in for little temperature difference.

http://www.coolmygarage.net/index.php?option=com_content&task=view&id=28&Itemid=1

 

[Professur]

Paint the roof white

 

[alecmcmahon]

Paint the roof white

better yet, line the entire roof with tin foil to reflect the sun.

Yeh.
Thats it.

 

[gabeancounter]

Use something like this. A large exhaust fan in wall mount with a switch so you only use it as needed.
http://cgi.ebay.com/DAYTON-30-INCH-...915?pt=LH_DefaultDomain_0&hash=item3f0a3170ab

 

[35mastr]

Why not just insulate it instead of burning all that electricity in a no win situation.

 

[georgelowcar]

That very well what i may need to do. I would prefer to keep the rafters open for storage and access, but perhaps i should rethink about at a minimal insulating the ceiling.

 

[omr]

keep in mind heat rises so take advantage of that instead of trying to push it back down and out the windows ..

i have seen solar powered fans but have no experience with them , i would think exhaust high intake low would work the best ..

 

[demographic]

Insulation, cooler in summer and warmer in winter.

Its a win win situation.

 

[georgelowcar]

i do have a concern about adding insulation to unheated, detached garage...

if i insulate the ceiling and walls, isn't the temp in the summer eventually get to ambient temperate (and probably higher) unless i vacate the heat or cool it? It will just slow down the duration before it heats up.

Basically, this is what i'm worried about after adding the cost of insulation: http://www.weatherimagery.com/blog/insulating-garage/

 

[omr]

i do have a concern about adding insulation to unheated, detached garage...

if i insulate the ceiling and walls, isn't the temp in the summer eventually get to ambient temperate (and probably higher) unless i vacate the heat or cool it? It will just slow down the duration before it heats up.

Basically, this is what i'm worried about after adding the cost of insulation: http://www.weatherimagery.com/blog/insulating-garage/

i didnt read the link but i was kind of thinking the same thing you mentioned , i think ventilation would be your best solution here ..

 

[rickairmedic]

Look at it this way in 6 months you'll be bitching your freezing your tookas off in there . Insulate it and add some AC and Heat .


Rick

 

[sdowney717]

Insulate just the rafter space. Use those foam channels to allow air to flow between plywood sheathing and the insulation.
Use a ridge vent along the peak.
make sure you have vented soffits where the air can flow in.

paint the roof white would help make the roof last longer as well as be cooler.

 

[alabamavolvos]

I have a 22x28 detached walls are insulated with sheetrock ceiling with no insulation in the rafters. There is a noticable difference in outside vs inside temps durring the summer. I cut a hole in the ceiling this spring for a future pull down access ladder and put some ply up there for storage. Not the easy access of opoen rafters but works well. Insulating the walls and putting in some type of ceiling will really cut down on the temp in the garage. I have a small window unit that can bring the inside temp to 75 when it's 90+ pretty quick. I was suprise how nice it is to work inside a garage @ 78 when it's in the 90s outside.

 

[slopecarver]

Insulation will certainly slow down conduction and nearly eliminate radiant heat, this will at least get it shade cool instead of sunny hot.

 

[787B]

Just to reinforce what the other folks here are saying, there are three solutions to your problem:

1. Insulate.
2. Insulate.
3. Insulate.

The slab (assuming it has one) is a giant heat sink. If you can keep the heat out, especially the radiant heat, it will be at or below ambient if it's well insulated. At a minimum insulate the ceiling and the South-facing wall. You can insulate against the roof if you want to keep the rafters clear.

Then you can think about ventilating in the evening and night when things cool down. With enough insulation, you can put in a 10-20k BTU window air conditioner and actually get down to that 80° and lower humidity to boot.

And hey! Welcome to the Garage Journal forums!

 

[Charles (in GA)]

Metal building? You don't say. Basically, the insulation will help keep the heat from passing thru to the inside, and eliminate that oven feeling. It also helps to eliminate sweating of the floor, etc, certain times of the year.

I use to work in an uninsulated metal building, the east wall would heat up in the early morning and by late morning, you could not get withing 15 ft of that wall, the heat just came thru the metal. My metal building at home is insulated with the bats you install and then screw the sheetmetal down on top of, not the best insulation in the world, but it works pretty well.

I open up the building, every door, and run the ceiling fans full blast. The fans push the heat down and the breezes carry it out of the building. Keeps the overhead heat to a minimum and you don't have the feeling you are in a broiler. Temp inside at floor level is within a degree or two of the temp at the peak of the building inside, 20 ft up, when the ceiling fans are running.

Charles

 

[bczygan]

Some other things to think about.
Plant trees. Evergreens to the north and large deciduous trees to the south to eventually shade the building. If you don't air condition, at least ventilate and use a dehumidifier for humid days, it makes a big difference. Cool, dry air moving over your skin will keep you comfortable, so inside fans at work areas help. Use a combination of methods.

 

[MKIndustrial]

Insulation, cooler in summer and warmer in winter.

Its a win win situation.

Couldn't be put any better... Do it once and never again.. One time cost....

 

[425hp]

Definitely insulate the doors, Owens Corning has kits @ Lowe's, very easy to install and really makes a difference in the temperature and noise.

 

[bigdav160]

i do have a concern about adding insulation to unheated, detached garage...

if i insulate the ceiling and walls, isn't the temp in the summer eventually get to ambient temperate (and probably higher) unless i vacate the heat or cool it? It will just slow down the duration before it heats up.

Yes. Unless the building has climate control the temperature of the garage will be outside ambient +the radiant heat gain. But as you can see from these post, there is quite a placebo effect.

If your building is in the sun get a radiant barrier put in. It works!

 

[787B]

Yes. Unless the building has climate control the temperature of the garage will be outside ambient +the radiant heat gain. But as you can see from these post, there is quite a placebo effect.

No placebos, just facts. My 988 sq-ft above-ground garage has uninsulated cinder block walls, two single-pane windows, a glass-paned man door, and a 16' composite thinly-insulated door with a couple of big gaps at the bottom where the slab had cracked and shifted (it's a rental). The only insulation is the un-air-conditioned living space above it (the house proper). Without any climate control it will not get above 85° on consecutive 95° days. With just 8000 BTU of window A/C it will stay at 75° all day long. So, at least in my case, having ~12 feet of ceiling insulation (the house) makes a big difference.

Maybe the difference is that even the ground gets hot in Texas?

(And maybe that it still gets into the low 80's/high 70's at night on those hot days.)

 

[georgelowcar]

Thanks everyone for the suggestions. I think i will start w/ some forced air output (attic fan) near one end of a dormer. In addition, i will insulate the rafter ceiling (leaving the rafter exposed for storage) to help with the radiant heat. If this doesn't help, i will have to insulate the walls as well, but i will start with the above and see what affect it has.

Its not a metal garage, its a wood+Fiber cement siding w/ Composition shingles and concrete slab. Some good size trees sheilding the south, but the roof is what is taking the heat

Now the research on which attic fan to install and what type of insulation to put in the rafter ceiling. Fun stuff.

 

[wolflrv]

I'm in the same boat your in with my 20x26 shop. I have a good thermometer in there and it's regularly 120 degrees in the afternoon. Even if I open the shop doors first thing in the morning and have fans blowing, it will still hit 110 degrees by 2pm. No way to work in that environment. My shop is a very nice, detached stick-built building with concrete floors, normal vinyl siding and shingle roof. It has open rafters and two gable openings on each end. There is a normal paned exterior door, one 2x3 window(large enough for AC unit which I have installed) and also a metal garage door. I've also insulated and chip-boarded one of the back walls, so far.

My plan is to install an attic gable fan in one end and to also insulate the ceiling using the rafter vents and insulation bats. I will also insulate the metal door. If that makes any kind of dent, then I might consider finishing the insulation around the rest of the walls of the shop and then maybe my window AC unit might have a fighting chance.

Right now my biggest obstacle is to find a buddy that wants to come help hang insulation at 3am, because that's the only civilized time of day to be in the shop!

 

[787B]

Wolf, you didn't say where you live and if beer would be provided.


Oh, and welcome to Garage Journal!

 

[omr]

I'm in the same boat your in with my 20x26 shop. I have a good thermometer in there and it's regularly 120 degrees in the afternoon. Even if I open the shop doors first thing in the morning and have fans blowing, it will still hit 110 degrees by 2pm. No way to work in that environment. My shop is a very nice, detached stick-built building with concrete floors, normal vinyl siding and shingle roof. It has open rafters and two gable openings on each end. There is a normal paned exterior door, one 2x3 window(large enough for AC unit which I have installed) and also a metal garage door. I've also insulated and chip-boarded one of the back walls, so far.

My plan is to install an attic gable fan in one end and to also insulate the ceiling using the rafter vents and insulation bats. I will also insulate the metal door. If that makes any kind of dent, then I might consider finishing the insulation around the rest of the walls of the shop and then maybe my window AC unit might have a fighting chance.

Right now my biggest obstacle is to find a buddy that wants to come help hang insulation at 3am, because that's the only civilized time of day to be in the shop!

where the hell you live ? the opens plains of africa ? lol im in south florida and have worked in every type of shop there is and with the garage doors open i dont think one of them was near as hot as you describe ..

 

[georgelowcar]

wolflrv - i have been looking at gable fans. These seem to be descent candidates. Low amps, descent CFM. let me know if you find something better.

http://www.amazon.com/dp/B002TXL5P0/?tag=atomicindus08-20


I may have to wait until the fall for installing the insulation batts in the ceiling, ontop of the rafter vents. Its just too hot. For now, in the heat of summer cutting the hole for the fan and setting that up, i'm sure to loose 10lbs in sweat. its 95 outside, probably 130 above the garage.

 

[Tinkerer49]

I have a GF 16 in my 3 car garage. It helps keeps the air moving but don't expect a dramatic drop in temp. It maintains my garage at or near ambient temp but more importanly it pressurizes the attic and cools it down. My garage is fully insulated.

I also use this an exhuast fan to rid the shop of noxious fumes (welding, paint odors, exhuast etc.)

 

[wolflrv]

Wolf, you didn't say where you live and if beer would be provided.

Oh, and welcome to Garage Journal!

Sorry..just updated my profile. I'm in Savannah, TN which is west tennessee. I'm 5 miles from where Alabama, Mississippi and TN come together.

I'll provide the beer, hamburgers, hot dogs, etc...although I'll be drinking iced tea or coffee...18+yrs sober!

And thx for the welcome!! So far I love this forum!!

 

[wolflrv]

where the hell you live ? the opens plains of africa ? lol im in south florida and have worked in every type of shop there is and with the garage doors open i dont think one of them was near as hot as you describe ..

Actually it's now almost 4pm..went out to shop to open it up and the temp in the shop was 118 degrees. And the thermometer is on an inside shaded wall far opposite of the metal garage door. I'm sure it's 130 in the rafters.

Just got back from Lowe's. Got 2 rolls of the padded R13 radiant barrier stuff and a big 20" box fan. Gonna try this to start with. They didn't have garage door kits in stock, nor the gable fan.

I'm in the process of restoring a 1985 Kawasaki Vulcan 750 that my brother gave me, but I can only work out there from around 5am till about 10am daily. After that it's just way too intense. We've been having 95+ degree days with +50% humidity and heat index staying over 100. I'm 50 yrs old and have no business out in that kind of heat unless I can make it somewhat civilized.

 

[wolflrv]

wolflrv - i have been looking at gable fans. These seem to be descent candidates. Low amps, descent CFM. let me know if you find something better.

http://www.amazon.com/dp/B002TXL5P0/?tag=atomicindus08-20


I may have to wait until the fall for installing the insulation batts in the ceiling, ontop of the rafter vents. Its just too hot. For now, in the heat of summer cutting the hole for the fan and setting that up, i'm sure to loose 10lbs in sweat. its 95 outside, probably 130 above the garage.

Yeah..that's the thing I'm looking for, but nothing in stock at local Lowe's(small town...no inventory). I'm gonna mount the 20" box fan up there and point it out the gable vent for the time being. I did this last year, but the smaller house fan I used, just didn't last very long.

I've been threatening to do the rafters every year, but this year may push me over the edge. I haven't really spent much time out there till this year..so this heat issue really needs to get solved. I don't worry about the cold, I'll work out there in 30 degree weather with a sweatshirt all day long.

 

[omr]

Actually it's now almost 4pm..went out to shop to open it up and the temp in the shop was 118 degrees. And the thermometer is on an inside shaded wall far opposite of the metal garage door. I'm sure it's 130 in the rafters.

Just got back from Lowe's. Got 2 rolls of the padded R13 radiant barrier stuff and a big 20" box fan. Gonna try this to start with. They didn't have garage door kits in stock, nor the gable fan.

I'm in the process of restoring a 1985 Kawasaki Vulcan 750 that my brother gave me, but I can only work out there from around 5am till about 10am daily. After that it's just way too intense. We've been having 95+ degree days with +50% humidity and heat index staying over 100. I'm 50 yrs old and have no business out in that kind of heat unless I can make it somewhat civilized.

with the doors closed im sure it's an oven but if you have the doors open and an ''exhaust'' fan pulling the hot air up and out from the top of the garage it shouldnt be any hotter than it is out side ..

 

[georgelowcar]

not sure if you have a ridge vent, but if you do, you may want to hold off on that gable fan. ... taken from airvent.com site

Can I install a power fan if I have a ridge vent already on my roof?
Mixing a power vent with a ridge vent can short-circuit the attic ventilation system just as a gable vent can as discussed above. This happens because air follows the path of least resistance. When the power vent turns on, it can pull air from the ridge vent, which could lead to weather infiltration and unbalanced airflow along the underside of the roof deck. When the power vent turns off, it acts like a roof louver — an opening on the roof without a motor. In this scenario, the ridge vent pulls its intake air from the power fan leading to possible weather infiltration and less than optimal ventilation along the underside of the roof deck.

 

[omr]

not sure if you have a ridge vent, but if you do, you may want to hold off on that gable fan. ... taken from airvent.com site

Can I install a power fan if I have a ridge vent already on my roof?
Mixing a power vent with a ridge vent can short-circuit the attic ventilation system just as a gable vent can as discussed above. This happens because air follows the path of least resistance. When the power vent turns on, it can pull air from the ridge vent, which could lead to weather infiltration and unbalanced airflow along the underside of the roof deck. When the power vent turns off, it acts like a roof louver — an opening on the roof without a motor. In this scenario, the ridge vent pulls its intake air from the power fan leading to possible weather infiltration and less than optimal ventilation along the underside of the roof deck.

i could see that being an issue in a closed attic but i wouldnt think it would be a problem in an open garage , well unless you had a fan on steroids

 

[wolflrv]

only have gable vents and eave venting...no ridge vent. But that is good info to know for sure!

 

[tommudd]

Just moving in last month I wondered how my 3 car would be when it got hot out. Its a pole building with a good bit of attic insulation and walls have foam in them. Metal roof has ridge vent on it. Today it was 97 here with the heat index at 104 so fairly hot out. Inside the garage it never got above 78 all day of course had the doors closed as much as possible to keep the heat out

 

[wolflrv]

Got insulation on garage door and box fan ******* in the rafters. Also a couple of pics of my shop currently. It's usually a lot cleaner looking, but I've got stuff everywhere atm, due to the bike restoration. We'll have to see in the next day or two how the temps differ.

Here's the garage door with insulation..this stuff is R13 and radiant barrier.

Here's the fan mounted in the gable. The blades are actually moving, guess the shutter speed is faster than I thought...LOL! You can actually stand in opposite side of shop and feel the air being drawn through the fan.

One angle of my shop. Wood stock is in the far back corner. All the bins and tubs are full of motorcycle parts and engine pieces. The whole top of the back bench is full of motorcycle parts too. Normally shop is a whole lot neater than this. The small table in the center is my tear down/rebuild table. It's just the right height to stand and work on the engine or sit on my creeper stool and deal with small stuff.

Other angle shows 4'x8' storage shelves and other shelf racks for miscellaneous parts and supplies. There's also a John Deere riding mower that sits in front of the yellow trailer, but it was pulled out to get on the ladder to hang the fan.

 

[Chieoze]

Living in the Philippines, this is also a problem. I don't think I'll be able to put in an AC since I'd like to save on electricity. I see an advice about planting trees. I think that will work since it can provide shade for the roof. I also saw something that can be used for the ceiling. It's a foam-like product that has reflectors on one side.

 

[georgelowcar]

wolflrv - i see similarities. The only diff is that i have a ridge vent, and not a gable vent...Not yet anyway I like the prototype you have setup. Please keep me posted on the results. Its suppose to be hotter than hell next couple of days around here.

other similarities - my inlaws will be passing down their 1960's suzuki (he can't recall the exact year) for me to have and restore. It could be fun, or miserable...Time and temps will tell.