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Question about half attic/closet insulation

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Nov 11, 2013, 10:37 PM
Question about half attic/closet insulation
I need some help. Winter is coming again!

On my second floor it looks like a walk in closet was added above the garage before we bought the house. That closet was obviously not insulated properly since it's freezing in there in the winter.

I went into the half attic (above the garage) to see what was done and it looks like they insulated the walls around the closet and I can see insulation under the floor. the rest of the attic is above the garage and was not insulated.

I since insulated above the garage hoping it would solve the problem but that closet is still freezing.

Should I close the floor joist? even if they put some insulation there, there is still a gap between the floor and the insulation. My only guess right now...

Since it's above an unheated garage, I'm at a loss.


Pierre in Denville, NJ

This message has been edited. Last edited by: pmetiv,
Nov 11, 2013, 11:11 PM
You need two things to make that closet warm:

1. Adequate insulation on all sides of the closet space, except where it intersects with living space that is already heated.

2. A source of heat in the closet.

If you do not have a H/A duct running into that closet, then it is going to stay cold no matter what you do. Opening the closet door will help a little, but a typical H/A system will draw away from the closet, not put any heated air into it. It may be simple, it may be hard, but you need to tp into your H/A system and run a duct into the closet. Plus, you will need some form of return air path from the closet to the living space.

Nov 12, 2013, 03:13 PM
Thanks for your answer. The walk in closet is only 5 x 8, and no duct travels in that area.

I don't leave the door open since it's so cold...may be I should try that.

More insulation will not help at this point I guess.
Nov 12, 2013, 07:56 PM
More insulation will not hurt, but if you want the closet to stay warm, first it has to get warm.

I'd take a look at the duct situation. A 5' x 8' closet will not take very much to warm it up - you could get decent results by running a 4" flex line into the closet space. Home stores even make a small, 4" round 'grill' that can be opened and closed. All you really need is a small path from the closet walls or ceiling to an existing heat duct. (provided you have forced air heat of course).

Nov 12, 2013, 08:38 PM
Thanks Jaybee!

Went back in there today and see one duct. I do have forced air heat.

Took a photo too. The "yellow" insulated wall is the closet and the "pink" insulation is the unheated garage under.

At the part where the wall meet the floor there's a 2in gap between the insulation and the floor.

The floor of that closet is very cold and I wonder if it's partially because of this.

My plan was to stuff some more insulation on top of what's already fill that 2in gap.

Just worried that it will create condensation since little air will be passing once I do that.


Nov 12, 2013, 10:18 PM
You want to fill that 2" gap at the bottom of the wall area. As far as condensation is concerned, you need to make sure that your attic space is vented - ideally soffit and ridge vents.

Nov 13, 2013, 08:48 AM
It's vented. Thanks for your help.