Garage Attic Insulation

[ste6168]

Wondering if insulating above my garage is worth it?

A bit more specific... I live in a 1400 sq. ft. ranch style (single floor) home with an attached single car garage (about 11x18). Two of the walls (interior) are 100% insulated, the garage door is a foam backed/insulated door, and I am fairly certain the the outside wall is insulated as well (I have drilled through the drywall and had insulation on drill bit), though not sure how good. Anyway, the attic is insulated well, EXCEPT for over the garage. I do not park in the garage, I use it as a woodshop. I live in NC, so winter temps are not that extreme, a small space heater keeps it plenty warm. Alternatively, in the summer (especially like right now) with temps climbing well into the 90s outside, it can get HOTTT in the garage. I do have a small window unit (undersized for the space, but the windows are small and I couldn't fit a larger unit), but it is not able to do much when it is so hot outside.

If you have read all that, the question is... Will insulating the attic above the garage, keep it cooler? Will it allow my small window unit to do a little better job?

Edit- To battle the "this thread is worthless without pics stuff" here is a picture of the house, as well as the shop (without window unit, which I put in that left window), and a picture of the hanging planters I recently made for the lady of the house.

 

[Stuart in MN]

If you have read all that, the question is... Will insulating the attic above the garage, keep it cooler? Will it allow my small window unit to do a little better job?

Yes, and yes.

 

[DC73]

yes, and yes.

x2

dc

 

[ste6168]

Yes, and yes.

x2

dc

Alright, so I am guessing the unanimous answer across the board is going to be yes, so a follow up to that... Is it better to have a company come in and do a blown in insulation, or just get some rolls from big box/building supplier and toss it up there?

I haven't shopped either way yet, this is a very new idea, but I am guessing the rolls of insulation would be cheaper method? Which is the better method?

 

[Stuart in MN]

For a single car garage it should be easy enough to install either rolls or bags of loose insulation yourself. I suppose you could blow it in (most places that sell insulation will either rent or let you use their blower for free) but it's small enough you can probably just get the bags, dump them out and level the insulation by hand with a rake or something.

Nice looking shop, by the way.

 

[psjoyal]

Beautiful place and great shop space. You will likely find that an insulation contractor can do it for very close to what you will buy the materials for yourself.

 

[barks]

This would give a contractor something to do for a half hour or so.

 

[ford fanatic]

Definitely worth it, just had my 28' X 40' garage blown in about a month ago. It makes a huge difference in temperature just walking into the garage from outside with no heat/ac source running.

Inexpensive considering how much time it would have taken me. It took them longer to set up, than to do the job.

 

[ckyle29]

Definitely worth it, just had my 28' X 40' garage blown in about a month ago. It makes a huge difference in temperature just walking into the garage from outside with no heat/ac source running.

Inexpensive considering how much time it would have taken me. It took them longer to set up, than to do the job.

X2. The contractor had my 1,800 SF shop completed in less than half a day spraying in to R-38. Total cost $1,200, that's with me already having the soffit vents installed. It can be in the 100's outside and my shop stays in the low-mid 80's without the A/C on.

 

[TerryH]

I had my 30x40 blown several years ago. Made an amazing difference along with insulating the overhead doors. My 18k btu window unit mounted in a wall does a nice job cooling it.

 

[NUTTSGT]

Yes, insulate the ceiling hands down. Once it's done, you'll wonder why you didn't do it sooner.

Do you have a ceiling in the garage already or is it open to the roof trusses or rafters ?

 

[DC73]

. . . .you can probably just get the bags, dump them out and level the insulation by hand with a rake or something.

I did what you suggest years ago when the bags of loose fill insulation were not compressed and it works very well for small spaces.

However, that was before they started compressing the insulation into small packages. Now, you need the blower to fluff up the insulation back to normal levels. I haven't seen the large uncompressed bags in many years. I tried the "by hand" method with one compressed bag of insulation and immediately decided against it. The stuff is like a brick and I just ended up with dense clumps everywhere.

As you mentioned, HD and Lowe's will loan a blower for free with enough bags of insulation purchased.

DC

 

[ste6168]

Nice looking shop, by the way.

Beautiful place and great shop space. You will likely find that an insulation contractor can do it for very close to what you will buy the materials for yourself.

This would give a contractor something to do for a half hour or so.

Thanks guys, appreciate it. I spend a lot of time in that little room, I try my best to keep it clean, organized, and comfortable. I have a "friend of a friend" in the insulation business, he is going to stop by one evening this week and give me an idea on cost. He said from the sounds of it, it shouldn't be more than a couple hundred.

 

[ste6168]

Yes, insulate the ceiling hands down. Once it's done, you'll wonder why you didn't do it sooner.

Do you have a ceiling in the garage already or is it open to the roof trusses or rafters ?

I have a ceiling in the garage already, which is 3/4" plywood. Past the plywood though, is the attic which is open to the rest of the house as well, so it gets HOT up there. After reading more of the comments on this thread, I am thinking the insulation will certainly make a difference.

Thanks!

 

[kbs2244]

First things first....
Is the attic vented?
Air in at the soffits and exhaust at the top.

 

[ste6168]

First things first....
Is the attic vented?
Air in at the soffits and exhaust at the top.

Yes. Vented on either end of the house, approx a 2x3 vent (plastic). We are getting a new roof soon, and will also have a ridge vent installed then. Also have several soffit vents around the house (maybe 1 every 10' as a guesstimate).

If you are asking about active ventilation, such as an attic fan, then no.

 

[cspcrx]

I have a 4 car garage and the builder did not put insulation in above the garage. I did the walls prior to them installing drywall. A year after moving in I had blown in put up and what I noticed was in the winter it keeps it pleasant and in the summer it keeps it cooler. The negative is we park two vehicles in it each night and it also does a great job of holding the heat in. For example I left this morning and it was 101 in the garage. I have two side vents on my garage, per code for a gas water heater. I have tried putting a fan in the upper vent blowing out to pull some of the heat out, helps some. The best thing I have found is if I open the attic stair it lets the heat rise into the attic and drops the morning temp of the garage. so it is a bit of a double sided sword.