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mm135
wall insulation: cellulose or fiberglass?

Trying to make up my mind: attached laundry room here in the mid-west, should I blow in cellulose or fiberglass? I'm having a hard time finding fiberglass, so i just may go with cellulose. Any pros or cons? its a small room, 13 ft long and 5 feet on one side.

Also, the rest of our 100-yr old house had cellulose blown into the walls, probably over 10yrs ago. Cellulose sinks over time i've read - do you think i should drill some extra holes and blow some additional cellulose in the other walls? There would be a lot of patching to do, but is this a good idea?

bp21901
Re: wall insulation: cellulose or fiberglass?

Am I right in assuming your wiring in the walls is not K&T? If so, the blown in cellulose will be fine to use.

As far as the rest of the house, can you check a couple stud bays to see if it has settled, and if so then go ahead and blow in some more. Maybe you could go exploring in a closet that was insulated to see if it has settled. That way the repairs that have to be done would not be in a high traffic area. It would give you an idea of how much additional would need to be blown in, also.

Shubi
Re: wall insulation: cellulose or fiberglass?

If you pump though one inch holes, cellulose will settle unless it's installed properly. Doing this method, you must drill 2 or possibly 3 holes per cavity in each floor. If you use a sidewall tube instead, you can properly dense pack your walls with cellulose providing a good air barrier and thermal boundry. Your walls must be solid enough to support a dense pack of 3.5# per cubic foot. Make sure you have any electrical work done beforehand, or you may end up installing wire molding to run additional wires after insulating. Also, homes with brick or stone exterior walls should not be insulated with cellulose. Bricks and stone allow moisture to seep through, which you don't want in cellulose insulation. Blown fiberglass is very expensive by contrast, and fiberglass batts do not effectively slow air movement.

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