Garage Insulation

[brentnelson]

I have a large 4-spot garage, Im looking to insulate the walls that are not already insulated. My question is what's the best way to insulate walls that are already drywalled? I have thought about using blow-in cutting a few holes to blow it in. I have also contemplated removing the drywall even though its taped and mudded.
What are your thoughts?

 

[The Cobbler]

if it's already taped I would get it blown in and then patch the holes .
now, if you had other reasons to remove the drywall, like it's all beat up, tons of electrical to do etc, then rip it off.

 

[billconner]

Agree with blowin. I'd prefer cellulose but could use fiberglass. I would not use foam. And I'd do the cellulose dense packed - 3 pcf - so it didn't settle.

I'm assuming this is a stick framed wall? Vertical studs with top and bottom plates?

 

[Jeffh40]

If it isn't insulated, it probably doesn't have a vapor barrier. Just something to think about.

 

[NUTTSGT]

I'm assuming this is a stick framed wall? Vertical studs with top and bottom plates?

This is my question.

Stick built, post frame or block ?

 

[bigdav160]

Unless you plan on using climate control for the space I would not insulate.

 

[dcg9381]

If it isn't insulated, it probably doesn't have a vapor barrier. Just something to think about.

Residential construction here requires a vapor barrier all the way around, but many builders cheap out on the garage and don't insulate.
You're not getting fiberglass/fill in there without some sheet rock removal. Filling cellulose is probably cheapest, but I've never done it.

I've seen foam companies that drill a hole in the sheet rock, insert a "staw" and fill the void from the bottom up, probably not a cheap service though. Closed cell foam would be a vapor barrier.

 

[Firstram]

If it isn't insulated, it probably doesn't have a vapor barrier. Just something to think about.

The PO's location determines where the vapor barrier gets installed. In the southern states, where it's hot and humid, the vapor drives in from the outside. Our barrier should be under the siding NOT the drywall!

 

[billconner]

If conditioning and needing an interior vapor barrier, paint. Use and moisture sources need to be known. Firstram is correct, and I don't know how to retrofit an exterior side vapor barrier.

 

[brentnelson]

To answer some of the questions.
1. stick-built
2. Tyvek wrap (located in Colorado very dry)
3. Heat only no A/C (for now)

The rest of the hose has blown in cellulose insulation, so most likely this will be the route I go just really didn't want to have to patch holes. But in hindsight, this will probably be the easiest way to go.
With the current heater, it keeps it fairly nice just want to help reduce the cycle time on the unit.
Thank you all for the input.

 

[Rusty Wrench]

... just really didn't want to have to patch holes.

My insulation guy used 3" plastic caps for blown in cellulose. Blown in from interior, that is. They set snugly 1/8" below the drywall surface. I think they have a bit of taper. One quick swipe of mud and patch is complete.

 

[billconner]

I've just used a hole saw, saved the drywall "cookies", and used then with a piece of 1 x2 or ply to fill hole, then tape and mud. Rusty's plastic caps sound interesting though.

The trick to the dense pack is a blower with an airlock - not what the big box stores usually have for free loaners.

 

[Brent T]

Unless you plan on using climate control for the space I would not insulate.

I originally thought this as well. Later, I had the garage insulated in prep for a mini-split and was surprised at the improvement it made just to have the insulation. The temp swings were much less severe and it's a lot quieter also. I now believe it's worth insulating even without climate control - at least here in hot/dry Phoenix, AZ. I now also have a mini split, and it's nice to be able to use the garage year round without it being miserable.

 

[billconner]

@Rusty Wrench

These?

Plug, Foam 3 in. (500/Bag)

Styrofoam plugs are used for holes in drywall and are recessed to accept spackling compound. They absorb little moisture, thus require fewer layers of spackling for a smooth finish. Please note: Due to shipping costs, you can purchase up to 3 bags of plugs. If you need more, please call us.

www.insulationmachines.net

 

[billconner]

Found these - no website though. Look good.

 

[The Cobbler]

it probably doesn't have a vapor barrier

and is not really needed in a garage . IMO especially if it's not continually heated

 

[Rusty Wrench]

@Rusty Wrench

These?

Plug, Foam 3 in. (500/Bag)

Styrofoam plugs are used for holes in drywall and are recessed to accept spackling compound. They absorb little moisture, thus require fewer layers of spackling for a smooth finish. Please note: Due to shipping costs, you can purchase up to 3 bags of plugs. If you need more, please call us.

www.insulationmachines.net

Bill, I remember them as plastic, not styrofoam. And I like those BPMI plugs. Variations on the theme.
I don't have shrinkage cracks but I think faced with the three choices I like the foam or plugs better.

 

[AC-WC]

Can't disagree with the vapor barrier comment but....I did cellulose on my old house and drilled from the outside to do it. No vapor barrier on the 1940's house. Did same on current house when we redid the exterior and cellulose on the east wall of the house. No vapor barrier on that wall. It was the only original wall that did not have insulation also built sometime in the 40's. Every other wall had been redone and insulated at some point in the house' life. For a garage that already has drywall I would not tear it out especially if you're not 'living' in it.