Dry walled garaged ceiling cant get to to insulate

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Aug 17, 2010
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I put a Window AC unit in my only garage window to cool it down while I work on my projects. It doesn't stay very cool and the ratting on the unit surpasses the room dimensions, its brand new and is blowing constanly. Yesterday I went up into the attic and noticed that the attic was closed off at the garage with plywood board. So I drilled two holes to look through with a flashlight. This room over the garage was not insulated at all. My two questions are: Can I just cut a hole in this wall so i can access this area from the attic and put insulation and have more storage space? And why was this sectioned off from the attic? Fire code? and if so how can I keep this fire code wall still up to code? can I install a very small door or will I just have to board it back up?
Firecode it is...you are right on. Basically to save your home when the garage has an issue. You will need to seal the holes off with fire caulk or spray foam which is rated for fireproofing. they seel it at the box stores.
I would make an access from the garage ceiling and save the piece you cut out, and trim it with some wood when you are done.

Have fun insulating, I would do it in the 4 am hour this time of year, and if you use fiberglass insulation, wash it off with cold water and fabric softener first.It helps.
Thanks for the quick response and info inspertorD. Is there any way I can use this for storage by putting a small door there instead of sealing it back up? Or would I have to build a entry from the garage to stay firesafe?
Thanks for the tip about cold water and fabric softer, I use packaging tape like a lint grabber and go over any exposed itching skin afterwords. I usually wear a one piece dupont paint suit, hat and respirator. I didn't use a respirator when I went up there the first time while I was kicking up fiberglass, is this a health issue?\
Does anyone thing I should approach this any other way?
My mistake, I see you said access from garage ceiling. so I can not cut a hole in this fire board at all and seal it back up or install a small door?
You need to separate the areas completely. This is called a fire safe wall, this is why it continues up through the attic.
And yes you can install a pull down stair set into the attic ceiling, or get someone to do it for you.
And this only works as long as this is not a truss roof.
good luck.:)
I do not know what a truss roof is. I got this definition off google:"Trusses are pre-fabricated, triangulated wooden structures used to support the roof." Well aren't all roofs truss then? This section i am trying to insulate is a triangle frame held together by those metal gusset things. There is a makeshift 2x4s walkway down the middle, so I guess it is meant to walk on and can support my weight (240lbs)? but the gussets come together right in the middle of what I suspect is a walkway, can I walk on this or will the gussets give out and i come crashing through the ceiling? Sorry for all the little questions, I am sure I should be able to walk up here but I do not have any carpentry experience.
I have seen many garages with truss roofs where the homeowners have used the space for storage. However, it is not recommended though. The easiest way to insulate the space will be to use blow-in insulation. The R-value of loose fill cellulose is R-3.2 to 3.8 per inch. Loose fill fiberglass has an R-value of R-2.2 to 2.7 per inch. Using blow-in insulation you will be covering several inches over the top of the joists to achieve a decent R-Value of insulation so storage will not be possible. Just cut a hole and blow in the insulation. You could make a raised platform perhaps to store some bulky light-weight seasonal items such as Christmas Decorations. Here's some more considerations and ideas regarding attic storage.
This is what a truss supported roof looks like:


As you can see, an attic space like this doesn't really lend itself to use as storage space.

And that's especially true if your blow-in insulation covers the tops of the bottom chords of the trusses cuz then you can't even store stuff without compressing the insulation.
Blown in insulation and no storage is the general rule, At least it will help your AC.
have fun in the shop and stay cool.;) Sorry couldn't resist.:D
Oh i got you. I thought you meant I couldn't put the ceiling ladder in if I had a truss roof. But can i stand on the frame of the roof? I actually use big pieces of partial board I get from work for free to put over the insulation and store Tupperware bins on. Does this seem ok in regards to what you said about no storage with blown in or any insulation? Will those gussets hold me? i am doing blown in insulation as it is the same price as the roll out kind and its non itchy and you can breath the dust in (Not that I wont use a mask anyway).
No storage, you cannot compress fiberglass insulation or it will not work...get any R- value. The floor area is really not built to support any weight, or high enough to get enough thickness of insulation, at least 8 inches.
My recommendation is to blow in insulation and seal it up.
It is also the least expensive route.And will give the best results.
But can I walk on the frame when I blow in the insulation or do i have to stand on a ladder the whole time?
You can stand up there, just be careful, too much walking around on a 2x4 truss can cause damage to the ceiling , nail pops and cracks.
I would span a piece of 3/4 inch scrap plywood to walk on as you work up there, just in case you misstep and put your foot through the ceiling.:D
Well, the question here is to do with weight ratings. You can certainly stand on it if you are normal weight - the thing is supporting the roof, it will bear your weight. What it is not rated for is moving weight of people living in it. Even setting aside the issue of the beams in inconvenient spaces, it is not strong enough for the weight of daily use.
You can certainly store things in it as long as you're sensible, and understand what it is, however, as others have pointed out this is not what it is designed for, and it is possible that if you use it a lot or put a lot of weight in it you may get popped nails or bowing - you'll see these if you get them though, so I wouldn't worry about it - just be sensible, and understand what the roof is designed for.
The attic is a terrible place to store anything like light plastic, paper, and cloth. I've just cleaned out my mothers attic where they had stored everything but the kitchen sink. Most of it had to go straight to the curb for trash pickup. I suppose the heat is the problem.
The attic is a terrible place to store anything like light plastic, paper, and cloth. I've just cleaned out my mothers attic where they had stored everything but the kitchen sink. Most of it had to go straight to the curb for trash pickup. I suppose the heat is the problem.

Well yes, that's another issue. ;)
It sounds as if the ceiling is drywall. Are the 3 other walls drywall, beside the house common wall? If they are, there is no need for the separating truss to be drywall (or wood sheathed) unless your LOCAL Code requires it, page #4: http://www.codecheck.com/cc/images/CC5thEdSample.pdf

Depends on when your garage was built with trusses: “The code now states that any space big enough to be used for attic storage must now be designed to carry that load whether it is intended for storage use or not.” From: Tri-County Truss Website

I need more information: 1.is the attic vented at the soffit and the ridge? 2. What is your location? 3. Is there a vapor barrier plastic on the attic ceiling above the drywall? 4. Since the common garage/house truss is sheathed, how many and what size vents are existing over the garage walls? (They may be minimal if someone else beside the builder installed the garage ceiling later).
There are much better choices than fiberglass.... (my last choice)

Be safe, Gary
Your last choice? Why? Don't you know any smart builders? This is THEIR first choice, 85% of builders to be honest. I have been a lisenced energy auditor, builder, hvac technician and more, and I feel sorry for anybody ignorant enough to dislike the worlds #1 insulation.
Well it's cheap, but that is about all it has going for it. It is pretty much the worst option on all other measures.