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Stephen Tashiro
05-26-2007, 12:51 PM
Is there a good DIY way to put insulation into an existing concrete block wall? I have seen contractors pump foam insulation from the top of the wall using a long tube that fits down into the cavities of the block. But I suspect this is not a DIY method. Is it possible to blow a dry insulation into the wall from the top?

Pat Germain
05-26-2007, 12:59 PM
I doubt this is something you can do yourself, but I admit I'm not certain about it.

Would it be possible for you to install insulation board over the the cinder block? You could then cover it with drywall. It would be a lot of effort, but would likely make a significant improvement in the thermal properties of your outside walls. It would also look pretty nice.

I lived in a cinder block house in Phoenix for several years. It was a pain. Among being difficult to keep cool, it was hard to hang anything on the outside walls without drilling major holes into the block and installing plastic plugs.

David G Baker
05-26-2007, 10:39 PM
Stephen,
I have read several forums that discussed do it yourself foam insulation and the usual solution was to hire it done because they know what they are doing (you hope), it can be a horrible mess if you make a mistake and the final cost is pretty much the same either way.
My basement has furring strips fastened to the concrete with foam board glued to the strips and Sheetrock nailed to the strips. Approximately 2 inches of space is lost if the insulation is 3/4".

Lee Schierer
05-27-2007, 8:48 AM
A number of years ago, we filled the walls of my FIL's house with expanded polystyrene beads. We had access to the top of the walls and just poured the beads down into the walls. It fills the block cavities and will even migrate slightly under window areas. It fills in almost like it was water. Their gas bills dropped enough to pay for the stuff in about the first year or two they had it in the walls. The stuff is commercially sold as "block Fill". Here is a link to at least one place that sells it. Block fill (http://www.thermalfoams.com/construction/Insulation/block_fill.htm)

David Epperson
05-27-2007, 8:53 AM
A number of years ago, we filled the walls of my FIL's house with expanded polystyrene beads. We had access to the top of the walls and just poured the beads down into the walls. It fills the block cavities and will even migrate slightly under window areas. It fills in almost like it was water. Their gas bills dropped enough to pay for the stuff in about the first year or two they had it in the walls. The stuff is commercially sold as "block Fill". Here is a link to at least one place that sells it. Block fill (http://www.thermalfoams.com/construction/Insulation/block_fill.htm)
I've done that, and it's effective. But we did it during construction before the top plate was put on. I'm just a bit unsure how one would gain access to the top cavities of an existing finished wall. I want to say the product we used was called Zonelite, or something like that...It was only 20 years ago when we did it. :D

Joe Chritz
05-27-2007, 9:58 AM
Not the method you were looking for but the best retro fit method by far.

Rip 2x4's in half. Fasten to the walls as furring strips every 16 inches with construction adhesive and a powder actuated nailer. Have a spray urethane insulation contractor spray urethane insulation about 1" thick on all the walls.

It is a bit more than foam board but many times better. Plus it is a complete vapor barrier as well. As with all foam insulation you will want to cover it with sheet rock or other approved covering.

Block fill isn't bad stuff but is difficult if not impossible to get in after construction. Something that forms a complete break to the wall is better.

Joe

David G Baker
05-27-2007, 10:33 AM
Joe,
I agree with the spray on foam. I haven't had it done at my place yet but there are several places I am going to have sprayed in the near future. A couple friends have had their pole barns sprayed, they say that it really seals the building so it is almost air tight and the heating bills go way down.