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Installing blow -in insulation

Posted: Wed Dec 05, 2018 4:05 pm
by Invest777
Hey guys

I have a outer wall that i want to insulate but I don't want to do it from the outside, so I was wondering is it sufficient to blow-in insulation from the inside?

Re: Installing blow -in insulation

Posted: Wed Dec 05, 2018 5:04 pm
by A. Spruce
Are you talking about drilling holes in the wall to install the insulation or do you have bare studs?

Re: Installing blow -in insulation

Posted: Wed Dec 05, 2018 10:23 pm
by Invest777
Drilling holes in walls

Re: Installing blow -in insulation

Posted: Thu Dec 06, 2018 1:09 am
by A. Spruce
I'd rather make the holes on the inside than the outside because it will be MUCH easier to make them disappear when you're done. I would check with local contractors that specialize in this type of insulation work and see if there is anything that would prevent them from working from the inside.

Something to watch out for, older homes, at least here on the west coast USA, have blocking down the center line of the wall, pre 1980's. I don't know when exactly they stopped doing it. If your house has this, it will double the amount of holes you will have to repair.

A hole saw will be used to punch the holes, make sure you save the donuts so you can use them to repair the holes later. You will also need some 1x2 that is 4" longer than the hole is wide. Insert a stick into the hole, screw either side of the hole, place the donut and screw through the center, tape and finish as you would any other patch or joint.

Re: Installing blow -in insulation

Posted: Thu Dec 06, 2018 7:14 am
by Shannon
iMO blow in is pretty much a waste of money in many homes when filling the walls “blind”. You are totally guessing if the cavity filled up or the insulation was blocked by wood,electrical lines, etc inside the wall and never filled the cavity.

Re: Installing blow -in insulation

Posted: Thu Dec 06, 2018 11:04 pm
by Aaron
Yeah, one might want to use a stud-finder or even those thermal imaging cameras on a cold day to attempt to "see" behind the wall... if you can where there are fire blocks and stuff in the stud cavity, you can make extra holes needed to fill those cells.

Old homes are a pain... I live in one.