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brick 1932
moisture in uninsulated closets
brick 1932

I have moisture and thus mold forming in uninsulated back walls of my closets during winter. It is a brick sided home from the 1930's and the walls are not insulated, just the attic. I do regulate the humidity and try to leave the closet doors open in winter since air holes and bottom gaps did not provide enough circulation. Would love to redo the back wall of each closet but need to know best procedure.

keith3267
Re: moisture in uninsulated closets
keith3267

You might consider louvered closet doors. Because the closet is located against a exterior wall an there is no heat source in the closet, it will naturally be colder than the bedroom and the humidity in the house will condense in there.

Insulating the exterior wall will help some, but without a heat source in the closet, it will still get colder, although not as cold as it gets now. Between louvered doors and insulation, it might be enough.

You could also put a vent in the top of the closet wall above the doors. This will draw warmer air from the ceiling into the closet as the colder air sinks down and spills out onto the bedroom floor.

You should also repaint the closet walls with a paint that has a mold abatement in it.

So a list of things in cost (lowest to highest) order. Work down the list until the problem is solved.

Vents above the doors ear the ceiling.

Louvered doors

Mold resistant paint

Insulate the walls

Put a heat source in the closet (leave the incandescent light on all the time).

brick 1932
Re: moisture in uninsulated closets
brick 1932

We did try a vent of sorts above and they have a good space below. We leave the door open all winter and still have the moisture forming so I'd like to do the insulation but need the best way to go about it and especially don't understand about vapor barriers. The walls are plaster/lath.

keith3267
Re: moisture in uninsulated closets
keith3267

There are a umber of ways to insulate the wall. Usually the biggest cost in time ad money is in repairing the wall after.

The lowest cost overall would be to blow cellulose into each wall cavity through a hole cut into the wall in each cavity. After this is done, you just patch the holes and repaint. This does not provide a vapor barrier though, but since you have to repaint, you can prime the wall with a vapor barrier primer ad then paint.

There are slow expanding foams that can also be blown in this way. If you can get a close cell foam, you won't need a vapor barrier ad it will be more efficient, but foam insulation is quite expensive, especially when doing just a small area. This would be more cost effective if you did the whole house.

Any other types of insulation will require tearing out the lath and plaster, installing the insulation a the recovering the wall, most likely with sheetrock. If you do this, using fiberglass batts requires the least amount of equipment, only a staple gun. Use either unfaced batts with a 4 mil or thicker plastic sheet over the studs and insulation, or faced batts with the wings of the paper stapled over the edges of the stud and not to the inside face of the stud as so commonly done. The wings should overlap a little. Do ot push the insulation up against the exterior wall, a little gap at the outside will be needed for ventilation. Then sheetrock and paint.

If you open the wall up and find mold inside the cavity, I would recommend that you treat the interior of the cavities with a sodium borate solution. Mix 2 parts boric acid (roach powder) with 3 parts borax (20 mule team) in very hot water. You can mix about 2.5 cups of the mix into one gallon of boiling water. Then use a garden sprayer or paint brush to apply.

brick 1932
Re: moisture in uninsulated closets
brick 1932

Thanks, that's kind of what I thought I was facing. I have three closets to do so it looks like I'll have to hire someone.

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