About to embark on a renovation of my family room to get rid of the horrendous paneling, so it will be gutted. My question is how to insulate these walls. Construction is from 1970, brick and block construction. There is at most a trace of fiberglass insulation in the walls. I can’t build out a 2×4 frame over the block as it would cause problems in lining up other doors, etc.
I’m thinking about foam sheets over the block walls (it’s too small a space to be economical to get someone to come out and spray foam). Can anyone point me to a good reference (A Taunton book, a thread here, other publication) that shows the details on how this should be done (what type of foam, how to install the foam, how ti attach the drywall) so I can spec it out for the contractor. Climate is the Washington DC area.
Thanks for the advice,
Carlos
Edited 10/20/2008 2:12 pm ET by ceb
Replies
Generally foam sheets, the thickest (eg, 3/4", not 1/2") that will fit, tightly fit between the 3/4" firring strips (that are probably already in place), with the gaps filled with squirt foam.
Before installing anything, though, the wall should be inspected for holes and cracks, with them being filled/caulked as appropriate. Also, the sill area where the stud wall rests on the block should be inspected for gaps and air leaks and foamed/caulked as needed.
This is a very reasonable DIY project.
Thanks for your response. Couple of questions
What type of foam -- is there a brand you recomend?
Is there an advantage to removing the old firring strips and laying larger sheets over the block walls and then putting new firring strips over the foam? Does this cause a problem in attaching the drywall?
I forget the brand and generic foam type, but one type -- generally a finer-grained foam -- has a better R value per inch than the standard styrofoam.There are special foam panels made such that you remove the existing firring, install the panels, then install new firring in notches pre-cut in the panels. This, of course, results in a thicker wall adding 1.5" vs 3/4".A lot of what you can do is going to be determined by how much thickness you can add.
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DOW makes a blue styrofoam that has the rabbit for furring-what Dan is talking about. Allows some electrical box mounting to block . You can "burn in" a trough to cover the wire using a torch CAREFULLY. These sheets work well and divorce the furring from contact with the block.A Great Place for Information, Comraderie, and a Sucker Punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Thanks. I can give up the 1.5" but 4" would get me over a floor vent. Do the big box stores carry the foam you mention with the cut out for the firring strip. I saw a DOW product there that was a pale yellow foam, blue liner on one side and a foil-type finish on the other.
How about a vapor barrier? Would any of these foams deal with that? Do I glue these on the block wall first? Again, if you can give a brand name it would be most appreciated.
Carlos
Edited 10/21/2008 12:56 pm ET by ceb
That's going to be a specialized product that the big boxes won't have... but might be able to order if you go to the pro desk. Otherwise you should go to a good building supply store.Rebuilding my home in Cypress, CAAlso a CRX fanatic!
I don't feel it's healthy to keep your faults bottled up inside me.
These guys might be a good source for you. Couple of locations in the DC area
http://www.kamcosupply.com/Locations/default.asp
This is the Dow product (Wallmate) that Calvin mentioned.
http://www.building.dow.com/na/res-us/products/styrofoam/wallmate_slotted.htm
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Thank you both. THe product with the channel for the furring strips looks like just the ticket. Does it need a vapor barrier on top?
Carlos
Edited 10/21/2008 3:08 pm ET by ceb