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can 2pound cc be sprayed below grade Post New Topic | Post Reply

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richard cozzolino cozzolino
Posted: Feb 28, 2007 10:17 AM
can 2pound cc be sprayed below grade
my ? is is it smart to spray foundation below grade with 2pd cc, will it deteriorate over time and is there an additive that can be sprayed on later or added to foam for termites.
thanks for any input
RC
Luke Kujacznski
Posted: Mar 01, 2007 07:44 PM
I have sprayed many below grade foundations without a problem. Use at least 2lb cc foam and cover the above grade sections with silicone, polyurea or a heavy duty stucco. If you are really worried about termites use 3lb foam.
Timothy Sonney
Posted: Mar 02, 2007 02:20 AM
We have sprayed ditch's for homes that have heating units located outside their homes. Example - Wood/Oil burner heats water that is pumped into the home.... they dig the ditch and we will spray about 3-4" of cc on the bottom.... they run their pipe...then another 3-4" on top of that then back fill carefully after the foam has reached total hardness.
richard cozzolino cozzolino
Posted: Mar 05, 2007 04:24 PM
why cant termites get into 3 pound foam?
thanks rc3
Luke Kujacznski
Posted: Mar 05, 2007 04:58 PM
I have never seen nor heard of termites "getting into" foam. Foam has no interest to termites because there is no food value. I said to use 3 lb foam because it is even harder then 2 lb thus more of a deterent. Why do you think that termites would "get into foam"? Where did you hear this?
Richard Russell
Posted: Mar 05, 2007 05:11 PM
While the foam has no food value for the insects, they can easily tunnel through it to get to the wood structure. In termite-prone areas, exterior foam insulation on foundations must be done carefully, and I think that it is Georgia (someone correct me) that forbids use of foam within 6" of the sill, so that an inspection band is left. One of the foam board vendors makes a borate-treated exterior foam product that is said to be ok for use (Performguard? Or am I thinking of something else?)

OK, here is a good URL that has info:

http://www.engext.ksu.edu/henergy/envelope/builderguide.pdf
richard cozzolino cozzolino
Posted: Mar 06, 2007 10:36 PM
that was a great site i was wondering if i could spray up to the grade line on the outside of the foundation wall and then spray the top 1 or 2 feet inside to avoid the termintes would that be as good as spraying all of the outside. RC3
Gerry Wagoner
Posted: Mar 07, 2007 07:32 AM
Hi RC. It would. I recommend overlapping the foam about 12-18".

oG
Thomas Kasper
Posted: Mar 08, 2007 12:39 PM
2lb can be below grade, but I think it must be dry ground. I wouldn't put it below grade if it were wet ground or if has a possibility of getting wet, without putting something on it to waterproof it. I have years of experience as a plumbers helper, we installed miles of underground pipe and removed miles of underground pipe. The pink styrofoam (2lb foam) insulating these pipes in low areas was soaked and spongy with only a couple years in the ground. It needs a waterproof coating like polyurea for basement walls in wet areas. For trenches like wood stoves we use pipe insulation in a 8" pvc pipe. If you want it to last.
richard cozzolino cozzolino
Posted: Mar 09, 2007 09:43 AM
thanks for the info. if i was to spray the inside of a new concrete basement foundation from footing to sill and they were planing on sheet rocking walls in a couple months after house is built, first how long can the sun hit it without causing damage. because framers might not get there for a week or so and second how long can it stay on the wall without sheet rock or fire proof paint. and finnaly should i not foam the concrete for 20 days to make sure its dry because the out side wall will be sealed with dampproofing and backfilled with dirt and concrete takes a while to dry out.
thanks RC3
Marc Kast
Posted: Mar 09, 2007 11:12 AM
The National Research Council of Canada has done a scientific study on this topic so I will not bore you with their findings but instead will provide you with the link to read the report. I think you will find it quite interesting.
http://www.cufca.ca/research/Basement%20Insulation%20Report%20-IR820-English.pdf
You can save this report and reprduce for anyone who inquires as to the suitability of foam on exteriors o basements
Posted: Mar 10, 2007 08:17 AM
marc, thanx for the link,,,added to the library..

the spfa has a good tech paper on spf below grade...AY-140 “Spray Polyurethane Foam for Exterior Subgrade Thermal and Moisture Protection”

didjaknow that "microbes" in soil can actually ingest the damp proof coatings that are currently used on foundations???

polyurea good!
Tim Regan
Posted: Mar 11, 2007 04:04 PM
If you are interested, we do have a below grade spray foam system/polyurea system we sell. Please contact me at t.regan@mchsi.com
Mike McGaughey
Posted: Feb 16, 2008 08:48 PM
spray polyurethane foams will not resist hydrostatic pressure. It must be protected with an elastomeric coating-preferrably a vapor barrier or product with a very low mvtr.
Rob Granger
Posted: Jun 07, 2008 09:15 AM
I have a job quote coming up which will require 2lb to be sprayed on the outside of a home. Where can I get the silicone and what is the brand name for a top application. Thanks

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