Cooling garage?

[Becky]

Do the vents I see near the bottom of garage doors really help in keeping a garage cooler? There is no window in the garage. Is there any other ways to help with cooling? Any input would be appreciated! Thanks!

Becky

[golfer808]

Our inspector said not to put vents in the garage door. In case of tornado I guess the winds could tear everything apart. Of course a tornado will probably do that anyways but I do think our builder knows what he is talking about. We just put a block of wood to keep the pull down stairs from closing all the way.

[saratogaman]

Yes, they do. To improve air flow further, I had a louver cut into the pull-down stairs.

[John_W]

The garage will never been any cooler than it is outside. So if it's 96 like it was at my house yesterday, it is a lot hotter in your garage if you have the door shut. Vents are OK if you have a fan pulling air through to the attic but I like a garage door screen better. On my 12' CYV garage door it cost $850.

Combine the garage door screen with attic pull down steps in the garage and then you will see a big difference. I leave the door to the steps cracked open about a foot and you can feel the air flowing through if you stand underneath. It's also helping cool the attic. Our last two electric bills have been $75 and $86 and we have our A/C on all the time.

http://imageshack.us/a/img708/8522/house21024x778.jpg

We have a screen that is a horizontal slider. That way you only have to open one of the 3' sections at a time when you go in or out and you can shut it behind you keeping pests out. With the motorized one piece door screen most people don't open and close the screen when they are working in the yard, that would be a hassle. The motorized versions are also about double the price.

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[BobnBev]

We were told that the louvers in the bottom of the door were there because we have natural gas. He said that code specifies this.

[gomoho]

You will get a million different opinions on this - my thinking is anything you can to do improve airflow will help in the garage. I am not so worried about the area above the house (attic???) 'cause I have nothing stored up there. I am sure it is hot as Hades and hoping the roof vents are handling what they can. I do have Christmas items stored in the garage and an extra fridge that I couldn't live without and still haven't seen an electric bill over $130. I remember $225+ where I moved from and was still hot so I'm not complaining.

We do have a window we try to keep open and the garage door is 1/4 open when we are home.

[George Bieniaszek]

I have a CYV and the garage door is a non-insulated one layer door. On a sunny day, this generates a lot of heat into the garage. What I did recently was to purchase some Styrofoam panels from Lowes and cut them to fit into the door. There was a remarkable difference in temperature. It's an easy DIY project, for the typical CYV garage door you will need six 4x8 panels and a razor knife to do the job. Took me about 2-3 hours.

[jimbo2012]

I was told it's a fire hazard to have the attic open or vented into the garage.

The Better way if you need it may be to put an exhaust fan in the garage directly thru the roof or side wall.

As far as insulating the door this would have little effect if the door facing north.

Mine facing north really isn't all that hot over outside temp.

[golf2140]

Don't we have garage doors designed to withstand huricane winds. Don't the vents defeat that?

[jimbo2012]

Don't we have garage doors designed to withstand huricane winds. Don't the vents defeat that?

Also vents feed oxygen to a fire!

[2 Oldcrabs]

If you are going to hold your attic stairs open, use a plastic soda bottle with the screw top on it. In the event of a fire the plastic will melt quickly and the stairs will close. Any fire will race thru the attic with open stairs. Some states require a "fire wall" in the attic between the garage & house.:mad:

[rubicon]

I had an overhead screen door installed. It helps but the screes do hold back some of the airflow. You can really feel the diference when raising the overhead screen door. However, i would never leave my garage opened and unprotected from entrance by critters... I had two fans placed i the attic and while the helped it is not a final solution

[Becky]

Thanks everyone for the info. Looks like a decision has to be made! Thanks again- very helpful info!

Becky

:BigApplause: to you all!

[Big47moe]

I have Romac garage doors and had them install an insulation kit for $300. It does make a difference.

[jimbo2012]

If you are going to hold your attic stairs open, use a plastic soda bottle with the screw top on it. In the event of a fire the plastic will melt quickly and the stairs will close. Any fire will race thru the attic with open stairs. Some states require a "fire wall" in the attic between the garage & house.:mad:

THat assumes there is a flame in the proximity of the bottle, not likely and I think U may be missing the point

[2 Oldcrabs]

THat assumes there is a flame in the proximity of the bottle, not likely and I think U may be missing the point

Does not take fire to melt a plastic soda bottle. The heat build up at the ceiling will melt the plastic. A friend of mine had a garage fire. The fire was near his door. On the top a cabinet about 26' away he a couple of cans of spray paint. The heat caused them to explode like a rocket and shoot thru the drywall like someone used a "hole saw" to make a perfect circle. The fire never got near the paint cans. I do not recommend anyone hold the attic steps open but, if you are going to do it I would use a plastic bottle instead of wood or something else that will withstand heat.

[Houselover]

Thanks everyone for the info. Looks like a decision has to be made! Thanks again- very helpful info!

Becky

:BigApplause: to you all!

I had The Solar Guys install a fan in the garage and 3 vents in the garage doors for about $600..Garage will not be cooler than the outside air. The attic air above the garage will kept moving which should help push the hot air out through the roof vents..

[cgalloway6]

I believe the soffet vents in the house are designed to work with the roof vent to pull cooler outside air into the attic and vent the warmer(hot) air thru the roof. If you introduce an easier path for the cooler air to enter, it will take that path. It may cool the garage and somewhat cool the attic over the garage but other areas of the attic may not get as much air circulation and you may find one room not as cool as before. Easy experiment if you have the garage vents - check the temp in each room for a few days, open the attic stairway a bit and again check the temps in each room for a few days. Better to get an average due to outside temp fluctuations, clouds, rain, winds, etc. As an old engineer used to say "one experiment is worth 1000 "expert" opinions".

[John_W]

I believe the soffet vents in the house are designed to work with the roof vent to pull cooler outside air into the attic and vent the warmer(hot) air thru the roof. If you introduce an easier path for the cooler air to enter, it will take that path. It may cool the garage and somewhat cool the attic over the garage but other areas of the attic may not get as much air circulation and you may find one room not as cool as before...

The OP was asking how to make the garage cooler, I was the one that mentioned the attic cooling as a by-product. I replied the garage screen would be the best solution and to get the air moving through the garage, crack open the attic steps (I use a small cardboard box). Since I've done this, I wrote that the attic must be getting cooler because my electric bills have gone down since. Initially my electric on a 2BR Masonry CYV were about $100 a month. Now our bills with the A/C on at the same temperature have been between $76 and $85 per month. The only other difference is I now have a 60" LED TV instead of a 50" plasma TV.


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[jimbo2012]

I have no attic fan, a/c always on.

My elec bill is $68.

Also depends on which build code it was built to, newer homes are better insulated