[ashkanr]

Hi,

I am planning to insulate my garage. The garage is unfinished, but the builder has finished the portion of the garage that shares walls/ceiling with the living space. The house is only 6 month old.
The rest of it is unfinished. When inside the garage, I can see at least four square openings that the builder has cut into the walls. I guess they are related to soffit ventilation.

I have many questions, please help me!

1- What are those holes for?

2- Can I cover them with plywood and then insert the insulation bats into the space between wall studs? If not, there will be no point in insulating the garage, since cold air can move inside?

3- I live in a cold area (yeah Ontario,Canada!); all I need is to sit in a warmer car when I want to head to work....the garage won't be heated, I just want it be warmer than -19! Should I put vapor barriers? or simply insulation bats held in place by friction?

4- Fire proof insulation, or simple traditional pink ones for garage?

I appreciate any answer to any of the questions above. Thanks!

***I have attached the pictures of the wholes, and an outside view of the garage for clarity.

 

[BigJim]

I have no idea why he cut the holes or left them open. If it were mine I would plug the holes, insulate and go on with it. If there isn't a house wrap on the outside of the house you may be out of luck on the barrier, you really don't want it on the inside as it will sweat.

 

[ashkanr]

I have no idea why he cut the holes or left them open. If it were mine I would plug the holes, insulate and go on with it. If there isn't a house wrap on the outside of the house you may be out of luck on the barrier, you really don't want it on the inside as it will sweat.

Thanks Jim.

There is no house wrap around mine.....so I guess I should forget about the vapor barrier....

 

[concretemasonry]

Why not just contact the builder to see what they are for.

Since the house is only 6 months old, they should be able to tell why they did it that way.

Dick

 

[Jackofall1]

Just a guess but I would bet the holes were used to raise the wall sections with a crane.....at least that is my guess. So yes cover them before you insulate.

Just use the pink batts, no vapor barrier as the garage will not be heated.

Are you going to hang drywall to? if not you will need to add something to hold the insulation in place.

It appears the ceiling is drywalled, is there insulation above?

How about the garage door? XPS on the door panels?

Mark

 

[ashkanr]

Just a guess but I would bet the holes were used to raise the wall sections with a crane.....at least that is my guess. So yes cover them before you insulate.

Just use the pink batts, no vapor barrier as the garage will not be heated.

Are you going to hang drywall to? if not you will need to add something to hold the insulation in place.

It appears the ceiling is drywalled, is there insulation above?

How about the garage door? XPS on the door panels?

Mark

Thanks Mark!

I will drywall it eventually, but I guess the insulation will remain exposed at least for two month.

Yes! the whole ceiling is drywalled and taped by the builder. They said they have spray foamed those areas to make them gas proof according to the code. But I am not sure if they have covered everywhere with foam insulation or just the seams...

The garage door is standard thin sheet metal. But I will cut 1.5" xps and insert into the door sections.

Hopefully these can keep me warm

 

[Jackofall1]

You really should be looking at adding some kind of mesh to support the insulation, otherwise, every time you open the garage door on a windy day the insulation will be blown out of the cavity.

Mark

 

[sixeightten]

I agree with the holes being used to lift the wall into place. By the pics it appears to be black where the holes are which may mean that felt was installed behind the brick. Just add the insulation and go if that is the case.

 

[Windows on Wash]

You may want to just put a kraft faced insulation up to avoid the wind wash and fiber agitation prior to the drywall.

No vapor barrier is required if the space is unheated.

 

[ashkanr]

I agree with the holes being used to lift the wall into place. By the pics it appears to be black where the holes are which may mean that felt was installed behind the brick. Just add the insulation and go if that is the case.

Today, I could talk to the builder. They said those holes are "nothing important" and I can cover them. They also mentioned they should be backed by black felt paper- But in fact they are not!
(I took the interior pictures at night-that's why they seem black)



Thanks everyone for your valuable hints and advice. I think the mystery is solved

 

[ashkanr]

You may want to just put a kraft faced insulation up to avoid the wind wash and fiber agitation prior to the drywall.

No vapor barrier is required if the space is unheated.

I'm a little bit worried about the warnings on the packaging of that type of insulation: "fire hazard if not covered with drywall....." :wacko:
But I really like the idea of those flaps that let you staple the whole bat to the wall....

 

[Jackofall1]

I'm a little bit worried about the warnings on the packaging of that type of insulation: "fire hazard if not covered with drywall....." :wacko:
But I really like the idea of those flaps that let you staple the whole bat to the wall....

Insulation covered with kraft paper is insulation with a vapor barrier / retarder, you don't want the vapor barrier with your installation, that is why I suggested a mesh to hold it in place.

Mark

 

[ashkanr]

Insulation covered with kraft paper is insulation with a vapor barrier / retarder, you don't want the vapor barrier with your installation, that is why I suggested a mesh to hold it in place.

Mark

I just saw a picture where the insulation bats were held in place by a string stapled to the studs. They ran it in a zig zag pattern.......it exactly the mesh idea, but with coarser grid.....I think that might be my solution
Thanks Mark.

 

[Windows on Wash]

Insulation covered with kraft paper is insulation with a vapor barrier / retarder, you don't want the vapor barrier with your installation, that is why I suggested a mesh to hold it in place.

Mark

Doesn't really make a difference in his case as he is not going to be conditioning the space whether it has a vapor retarder or not.

Kraft paper is not a suitable ignition barrier so you will need to cover it.

Putting it up with mesh is fine to if you don't disturb it, which you will.

I would put up and unfaced batt (high density) and just drywall it and be done with it.