Using SPF in a plastered wall.

Can you give me the pro's & con's of having SPF used in any already plastered wall? These wall would either have very old insulation or none at all.

Asked by David Nehring
Posted Mon, 01/30/2012 - 10:36

Tags: General questions

David,
Do you plan on opening up the wall from the outside, to get full access to the cavities? Or were you planning to drill holes in the plaster, in hopes of pouring or spraying the insulation through the holes?

Answered by Martin Holladay, GBA Advisor
Posted Mon, 01/30/2012 - 15:49

spf spruce pine fur.... or spray polyurethane foam... or special people fomenting...

I can't spell to save my life today!....

What kind of fur was I thinking.... bear... mink...beaver... tanks... Martin

Answered by aj builder, Upstate NY Zone 6a
Posted Mon, 01/30/2012 - 15:57

Edited Mon, 01/30/2012 - 17:04.

I thinking about just drilling holes thru the plaster.

Answered by David Nehring
Posted Mon, 01/30/2012 - 16:12

David,
Assuming we are both talking about spray polyurethane foam, there are products that have been developed for this application. Here is one:
http://www.fomofoam.com/existing_homes.htm

However, I think dense-packed cellulose makes more sense. These pourable foams can be tricky to install without problems.

Answered by Martin Holladay, GBA Advisor
Posted Mon, 01/30/2012 - 16:37

Edited Mon, 01/30/2012 - 16:47.

Do you have brick cladding? If so, insulating the wall may cause freeze/thraw problems you haven't had in the past. Learn more here: http://www.buildingscience.com/documents/reports/rr-1105-internal-insula...

Answered by mike dss
Posted Mon, 01/30/2012 - 20:25

David,
what kind of wall are we talking about here? Frame, masonry, brick on frame or what? Drill a hole and let us know what you find. Your answer will be important for what we recommend.

@ A.J. - looks like you had a fun lunch today - or was it just the stress getting to you :-)?

Answered by Torsten Hansen
Posted Mon, 01/30/2012 - 21:50

All the insulation contractors I know have abandoned drill and pour formulations. IIRC, combination of bad flow and inconsistent curing.

Answered by Dan Kolbert
Posted Mon, 01/30/2012 - 22:59