How to insulate block walls above grade?
Want to make sure I’m on the right path in insulating my first and eventually second floor walls. They are block and brick all the way to the roof line, no wall insulation currently.
Thinking of 2″ rigid foam. Any difference between XPS or EPS for this situation?
Planning to glue the panels with PL300 unless there are other suggestions.
Any recommendations on tape for the seams?
Lastly, I’ll be framing 2×4 walls in front of the foam so I can run electric. Should I put some unfaced batts in these as well?
‘Man who say it cannot be done should not interrupt man doing it’ ~ Chinese proverb
Replies
Shameless bump.
Anyone?
We insulated a block foundation with foam in the blocks. Helps alot in a finished basement.
As in you drilled into the blocks and injected foam? What I want to insulate isn't the basement, but the walls above.'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
Yes
If you haven't laid the block yet, you should really investigate ICFs.
Bob's next test date: 12/10/07
Thanks Blue,While I would love to play around with ICFs, this is all in an existing house. Just trying to make lemonade out of the fruity house I've got.'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
Okay, back to your original question.
Make sure you are using compatible glue. Some glue eats up foam.
I'll let the other insulator experts comment. I'll be a learner here.
Bob's next test date: 12/10/07
Good point on the glue, thanks.Am thinking either the PL300 or the gun/foam at EFI here
http://www.energyfederation.org/consumer/default.php/cPath/21_28_1268Assuming that either of those are ok for either EPS or XPS.'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
I think both should work with EPS or XPS. I know for a fact the PL will not eat the foam.
I wouldn't use foam on the outside near grade unless it has borate in it, if you have critters in your area -- which you do in Alexandria.
Blly
Edited 4/24/2008 10:33 pm ET by Billy
Thanks. This is all for the inside, so I'm hoping that I don't have to worry about critters :)'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
I think the extruded foam is superior, plus is comes with T&G edges. If you cut and fit it tightly, you only need a few dabs of adhesive here and there to hold it in place. Framing over that w/2x4 walls is great, the batts will certainly add extra R-value to the wall.
I don't think taping the seams is really necessary, but if you want to tape them with something that will hold, try to get some 4" wide Tu-Tuff, or Tuck tape. Foil tape might hold, as might tyvek tape, but I wouldn't count on it holding for long.
Thanks, that's very helpful.You have a preference on the adhesive?'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
I don't have any preferences. PL and Liquid Nails both make an adhesive that is specific for foam panels. I can't remember what they call their foam specific products but read the labels since most construction adhesive is NOT compatible with foam board, the solvents will melt the foam.
Thanks. I'll try the PL that's appropriate for XPSDo you run adhesive in between the panels to fill the gaps? Just butt them tight together?And, do I need to brace the panels as the adhesive sets?'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
I run the PL on the edge between the panels but it's probably ovwerkill. If you're using PL and XPS you don't need to brace. Every five minutes I press on the panels to make sure they are staying in place until the PL sets.
I had no problems with the regular PL adhesives and foamboard. Read the print on the tube and it will tell you if there's a problem using it with foam.
Billy
Spray foam.John
J.R. Lazaro Builders, Inc.
Indianapolis, In.
I butt the panels as tight as I can. If you use the panels with T&G edges, you should get snug fits. I've never glued the panels together, just snug them with dabs of adhesive on the back to hold them in place. After all panels are in place, you can go around with a can of spray foam to fill any gaps around the edges. You can use pieces of strapping (1x3) as spring boards here and there as necessary to put slight pressure on the panels to hold them in place until the adhesive sets, or place a small diameter tapcon, or similar concrete screw with a large washer to hold them in place.
My buddy bought a block wall house that was a money pit for heating. We get snow from late November early December and yesterday I saw my whole lawn.
I built a steel stud wall inside the blocks 5 inches. We filled the 5 inch cavity with R22 fibre then filled the steel studs with full 16 inch wide R10 fibre. New house wrap and siding on the out side with PVC windows foamed in and wide window jamb extentions. Two heating seasons later and the owner just told me the other day how warm and quiet his house is. This system was alot cheaper thatn foam.
Have a good day
CLiffy