Hiya,
I live in Northern CA and our new house has a 2 car garage that is an oven during the bulk of the day. It’s insulated and drywalled with a large 2 car metal garage door and 2 small low e windows plus has a metal man door. We use it for storage at times and I am concerned about the heat damaging the items being stored. It’s as hot if not hotter than it is outside.
What can I do to try to cut down on the heat in the garage? I don’t want to “cool” it so much as keep some of the heat out.
It’s very drafty around the garage door which probably doesn’t help but I don’t know how to do anything about that. It’s definately got more gap around the door than our old house did.
Replies
New door weatherstrip and maybe a new or bigger bottom seal will close it up a bit better. An insulated door would help a boatload. Sun on an uninsulated garage door transfers heat inside pretty quickly. To cool it off you could open it up in the evening/early morning and let nature bring down the temp. Perhaps an exhaust fan up high on the wall, but don't forget to open the windows when in use or connect it up to a power vent that would open on call. Locate the incoming vent on the cool side of the house. A tight well insulated garage should keep the cool most of the day. By the way, where's the water heater and furnace located? You wouldn't want to power vent the space if they're located in the garage.
You say it's insulated. Side walls and ceiling?
Remodeling Contractor just outside the Glass City.
Quittin' Time
Edited 7/21/2003 6:35:38 PM ET by calvin
The house is less than a year old so I assume the weather stripping on the bottom is good. There is no weather stripping at all on the sides. It's just the stucco wall of the house then the door mounted next to that.
I took a few images which will hopefully show you the gap around the door and how the wall is finished (or not).
http://www.leadman.net/images/GarageDoor001.jpg
http://www.leadman.net/images/GarageDoor002.jpg
http://www.leadman.net/images/GarageDoor003.jpg
The water heater is in the garage but the furnace is in the attic and since it's been hitting over 100 lately I don't think we'll be using the furnace much.
It's not so hot during the morning but by late evening it's an oven. I can't say much about the insulation other than it's there. The whole house is suppose to be insulated including inside walls.
I'll buy one of those door insulation kits and see how much that helps. 2 sides of the garage share common walls with the house and the other 2 get the brunt of the sun during the later half of the day. Even when the sun is on the back of the house the garage isn't cool.
I don't really want to "cool" the garage so much as keep it from heating up if that makes sense. It's not used as living space so I don't mind if it gets warm but I don't want it getting hot.
Laura,
One of the first things I would do is create shade on the sunny side with an arbor or trellis system. I would install a power vent thermastatically controlled.insulate the garage door and put in a window unit a/c .
ANDYSZ2I MAY DISAGREE WITH WHAT YOUR SAYING BUT I WILL DEFEND TO THE DEATH YOUR RIGHT TO SAY IT.
Thanks for the info but there is no place to install an arbor, it's a small lot and the garage sits 5 feet from the lot line. Those 5 feet are filled up with a sidewalk. I'd love to put in some sort of shade but it's not an option. :(
The windows aren't large enough for an A/C unit but I don't really want to cool it so much as keep it from getting so hot.
The garage in our last house never got this hot and we were even able to keep a freezer in there. In this house I think the freezer would burn itself out trying to keep up.
I'll check into what a vent might cost to install.
My thoughts are there are possibly 2 problems. The first would be that the overhead door looks like a cheap stamped steel door with no insulation. Replacing thedoor and adding weatherstripping would be expensive, but would almost certainly help.
Getting rid of the water heater would also help, but I doubt that's an option. Turning the thermostat down a hair during the summer might help.
What about ventilation in the attic? If the heat from the roof can't escape, it will heat up the garage. Check for soffit and ridge vents.
There are no new sins ... the old ones just get more publicity.
It's a tract house and while the price wasn't cheap the workmanship sure seems to be. There isn't a straight wall in the place and you can actually see the dips in the downstairs floor. Live and learn, I guess. We still like it better than our old house but I'll never buy another house that I don't have control over the quality and items going into it.
I can get an insulation kit for the door which might help but I don't know how I could weather strip the sides it since the gap seems to be to needed to allow the door to close. Is there weather stripping of some type designed for this type of door/installation? Replacing it would be a last resort.
I'll check for the vents. It has it's own attic access so it shouldn't be to hard to get someone to add them if needed.
Laura, the door weatherstrip (can be had from a garage door co.) or maybe HD..............is a vinyl sweep attached to an extruded vinyl or plastic stop. Overall, maybe 2-1/2" wide by 1/2" thick. You should be able to fasten it to/through the stucco. The sweep remains flexible forever. You would apply it with a little pressure against the door when the door is shut. Lemme know if you need a picture of what I'm talking about. You'd need two sides and a head pc. If the sun hits that uninsulated door, you're taking alot of heat from the inside of that. Can't remember if you showed it, what color is the outside of the door?Remodeling Contractor just outside the Glass City.
Quittin' Time
Pictures would be appreciated though I think I know what you are referring to. The door is white on the outside.
I have seen side installation kits, look like a mini broom.
Well, as already mentioned, attic ventilation, and door insulation, are the obvious places to start.
Does the sun shine on the doors? If so what color are they? If they get any direct sun I'd at least add the insulation kits and vinyl seals around the doors. If your windows get any direct sun, some reflective blinds would help slow solar gain.
What color are the shingles? White shingles gain a lot less heat then dark brown. If dark shingles then attic insulation and venting is crucial.
How much insulation is in the attic? Perhaps you could blow it in to an R38 or so. Also check to make sure there is insulation under the sheetrock on the walls, there may not be. Is the metal man door insulated? If not and particularly if it gets direct sun, it'll add a lot of heat to the garage also. Mine gets lots of late afternoon sun through 4 long windows that really heats things up at night.
My house has a two car garage on the West side of the house. The old fiberglass doors got some sun in the evenings. Insulated doors made a big difference. Even w/o the vinyl seals (which I still intend to add someday). Adding more venting seemed to help some. Eventually, I'll upgrade from the current R15 or so in the attic, which should help more. The walls are 2x4 with fiberglass (R12 or so).
Look at all parts of the structural system, then address the areas where you think the most heat gain occurs first.
Anyway, that's my ramble.
If looks aren't a requirement, you can paint the roof with a special aluminum coating or with a white one like Sno-coat. I think each needs to be recoated periodically. I have been told that the aluminum stuff looks pretty bright initially but tones down somewhat after a year or so. I am familiar with putting the stuff on hot-mopped roofs, but don't know about putting it on composition or shingles.
The sun shines directly on the garage in the late afternoon. The door is a standard tract house white. It is metal if I wasn't clear before. There is only 1 small ~6" window on the garage that faces the sun and it's covered with a sun shade.
Without cutting a hole in the drywall I can't tell what insulation is in the walls as all the garage walls are drywalled, textured and primed. I do know it's insulated as I can see it from the utility access panels but I can't see the backing to know what the R factor is.
The man door is in full shade thank's to the property fence. And it is insulated.
The shingles are amber cement shingles.
The attic has blown in insulation but I don't know how thick it is. It's been 100+ lately but I'll try to check it out early one morning when the garage isn't to hot.
If the walls are insulated, the actual R value doesn't matter much, as you're stuck w/ whatever's there. I'd guess 3.5" fiberglass batts.
Sounds like your door is the weak spot. Sun shining on metal, even white metal will heat it up quickly, and it will reradiate that heat into the garage. Insulated doors is where I'd start. I put in 2" thick metal doors (about $400 ea.). Took my BIL and me most of a Saturday to do it. Most metal door makers will sell you a retrofit kit, which'll be cheaper, but not as effective. I think these just glue foam panels to the inside of the doors.
Other then that attic ventilation and insullation levels would be key to slowing heat transfer into the garage.
Where's Ron T or John Sprung or any of you other Left Coast contractors?
My project in S. Orange County involved rebuilding the garage among everything else. The building code I had to work with REQUIRED multiple open high and low vents in the garage, especially when a gas appliance was in that area.
Have you an electric water heater?
Perhaps you were told the garage was insulated, but is it really? Mine faced due south. I got tons of sun on the door. My garage was nice and cool. But I also had a nice insulated door.
I say you need ceiling and roof vents for this area, in addition to the previously mentioned wall ones. Then more insulation, and then change that big door into something insulated. In that order.
The water heater is gas.
There are several vents in the garage attic as well as wall insulation.
I'll check into the garage door insulation and weather stripping or replacement of the whole door and hopefully that will make a big change.
My garage has just heated up, too.
The reason is the access door going into the attic above the garage was moved and not put back in place. In certain wind conditions, directions, etc. the hot air from the attic would fall down into the garage, cooking everything.
You mentioned the furnace was in the attic. Is there a semi-hidden make-up air vent going from the garage to it's attic? Or some other means of air coming from a higher pressured attic into a lower pressured garage?
You may have to close that and/or provide other forms of make-up air / attic ventilation.
When I was working in the Phoenix area I came across an article about research done at the U in Tempe on energy conservation for hot summers.
I don't have a copy, but from what I remember the primary recommendation RE: Garages was that they should face south - even if there is no roof overhang. Facing west was the worst.Any jackass can kick down a barn, but it takes a carpenter to build one.
Is the garage roof vented?
I have a completely unfinished uninsulated garage and it to is an oven. I believe the asphalt shingles heat the under-roof area to 110 or more. I also believe that if the garage had a ridge vent and under-eave vents the garage would cool to something closer to the outside air temperature.
My next garage with have vents and perhaps a fan.