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Author	Comments
Eric Machemer Posted: Oct 29, 2008 02:46 PM	CC on concrete foundation I recently sprayed 2" cc on a concrete foundation wall. After depth probing we added another 3/4" in one area and the entire sheet went "BANG" and came loose from the concrete. Temperature of the concrete was 60 degrees prior to spraying and appeared dry. Foundation wall is about 4 years old. When we you came back the next morning there was a 3/4" space between the slab floor and the bottom of the foam. Any thoughts out there?
SprayFoamSupply.com Posted: Oct 29, 2008 10:06 PM	Sounds like the foam was shrinking after you sprayed it and it sheered itself off of the wall. I do not think the extra 3/4" had anything to do with it. Were you on ratio? Did you have enough pressure and heat to get a good mix of the chemicals? What proportioner do you have? George
Eric Machemer Posted: Oct 30, 2008 05:46 AM	E30 - Air Purge gun w/ 29 tip. Proportions were great and the foam looked awesome. We were just finishing a whole house and everything looked really good. Proportions were right on the money based on amount of A and B used. We've sprayed a good number of foundation walls before and had some minor spots where foam didn't bond real great (maybe a little residual oil from concrete forms). but never anything like this.
Posted: Oct 30, 2008 06:30 PM	How were you ratios based on the machine pressure gauges? Tim
Gerry Wagoner Posted: Nov 28, 2008 09:38 AM	We have had a similar experience twice in the last 20-days. We are conducting an experiment currently -- priming the wall first to see if that will solve the adhesion problem. The foam goes on in two hours from now, I'll report our findings. It is closed cell foam, too. oG
Gerry Wagoner Posted: Nov 28, 2008 09:48 AM	Feel free to email me FoamRun and we can discuss the brand(s) of foam we are having this problem with.
Gerry Wagoner Posted: Nov 28, 2008 01:59 PM	The experiment failed. After priming, this foam disbonded from the concrete surface just like the other batch. Concrete surface temperature was 57° - 63° F. Somebody better figure this out at the manufacturer level, and pronto. oG
SprayFoamSupply.com Posted: Nov 28, 2008 08:06 PM	Hey Gerry, What was the pass thickness that you sprayed? George
Posted: Nov 28, 2008 09:26 PM	look at your batch number for the resin,, try another lot,,,sounds like the environmental conditions were well in order,,and i am confident of your processing skills,,so i would be suspicious of a lot that just aint workin the way it should,,,use it for wall foam,,it will stick fine,,concrete bites,,,(figuratively)or have your supplier exchange it for a different number,,, sometimes one number will perform better than another,,,particularly in suspect substrates.. we are only as good as our products manufacuturers,,,(i tell em to add more of the sticky stuff and they just look at me like im a moron or sumpin!!!) and george is thinkin...dont hog it,,,shine the first pass,,1/2" or less and then build on the shine,,,keep the temps down as low as you can so as to still allow good impingement and blend and thus foam production,,but low enough to reduce the thermal shock/shear at the substrate to foam interface,,,(keep the temp swing as low as you can)plan on 20-30% more material for the shine and build,,,pending on the profile of the foundation... good luck ger.. 'dude
Posted: Nov 29, 2008 09:32 AM	Foamdude, when you say "shine", are you referring to the look of the slow reaction from quicker passes on concrete? if so, how fast do you build onto that pass? would you wait for it to react (10-15 seconds)? like using the "shiny" pass to help warm the concrete? As far as temps, how low can you go? i know each situation/foam is different, but how low have you let the A & B get? I usually spray my pass at one time with good results, but this has happened to me in a crawl space once. and i had to scrape it off and redo. -aaron
Bryan Kwater Posted: Nov 29, 2008 09:50 AM	We have also had this same problem recently. Luckily it was just on a fairly small area. We were trying to spray between 1/2" and 1" in one pass. Ass soon as the foam cooled (approx. 10 minutes) an area approx. 4'x10' would pop off. We had the problem as soon as we started spraying a crawlspace. What ended up working for us was to put a flash coat as thin as possible and let it sit for 10 minutes or so. Then when we applied the rest of the foam at 1" thick, we had no bonding problems. The block walls looked dry before we sprayed and the block was about 50 degrees. The causes could have been that the blocks sweated when the foam heated it up, or that there was some sort of residue on it. Every crawlspace that we have sprayed since then has not been a problem with the flashcoat being sprayed first.
Gerry Wagoner Posted: Nov 29, 2008 10:24 PM	The pass was 1" and 1.5" oG
Gerry Wagoner Posted: Nov 29, 2008 10:27 PM	I believe that Dylan tried a flashcoat last week and that failed as well. I'll review with him Monday morn. og out
Glenn Gamblin Posted: Dec 10, 2008 10:29 AM	I have had similar experiences in the past when spraying concrete, and thick steel as well. The only fix that I found is to use a forced air heater to heat it up a bit extra, because the thicker material draws so much heat from the foam. I might be completely wrong here, but I have never had the foam turn loose from warm concrete so im sticking with it.
Gerry Wagoner Posted: Dec 10, 2008 12:23 PM	Was that a pun?
Glenn Gamblin Posted: Dec 11, 2008 08:46 PM	I do believe so!
Brian Currie Posted: Jan 15, 2009 09:21 AM	I have sprayed alot ot foundations cold,wet, hot whatever and never had any problems.I truly think it is the Permax that makes the difference
Posted: Mar 23, 2009 08:13 PM	I have noticed this with walls as well, but only when I totally fill the whole stud area with foam. If I spray a light cote first and then come back later it doesn't seem to happen.
Dennis Davidson Posted: Mar 24, 2009 10:08 AM	We've had the same problem before too. It's not the foam (rarely is) and you should never apply a thin 1/4"-1/2" layer on a cool surface either. This can set you up for a failure too. Try spraying a 4-5' pass, 1-2" thick, then skip a pass, do the next one and skip one. I know, sounds like dancing. Later ( 1/2 hour to an hour?) go back and fill in the gaps. Haven't had any problems doing it this way.
Posted: Apr 06, 2009 09:48 PM	whos foam was it that popped of the concrete deck? It was not a BASF Blend was it?
Posted: Apr 07, 2009 05:52 AM	(you mean it could be product variation from lot to lot??? damn,,,,,)

Author

Comments

Eric Machemer

Posted: Oct 29, 2008 02:46 PM

CC on concrete foundation

I recently sprayed 2" cc on a concrete foundation wall. After depth probing we added another 3/4" in one area and the entire sheet went "BANG" and came loose from the concrete. Temperature of the concrete was 60 degrees prior to spraying and appeared dry. Foundation wall is about 4 years old. When we you came back the next morning there was a 3/4" space between the slab floor and the bottom of the foam.

Any thoughts out there?

SprayFoamSupply.com

Posted: Oct 29, 2008 10:06 PM

Sounds like the foam was shrinking after you sprayed it and it sheered itself off of the wall. I do not think the extra 3/4" had anything to do with it. Were you on ratio? Did you have enough pressure and heat to get a good mix of the chemicals? What proportioner do you have?

George

Eric Machemer

Posted: Oct 30, 2008 05:46 AM

E30 - Air Purge gun w/ 29 tip.

Proportions were great and the foam looked awesome. We were just finishing a whole house and everything looked really good. Proportions were right on the money based on amount of A and B used.

We've sprayed a good number of foundation walls before and had some minor spots where foam didn't bond real great (maybe a little residual oil from concrete forms). but never anything like this.

Posted: Oct 30, 2008 06:30 PM

How were you ratios based on the machine pressure gauges?

Tim

Gerry Wagoner

Posted: Nov 28, 2008 09:38 AM

We have had a similar experience twice in the last 20-days. We are conducting an experiment currently -- priming the wall first to see if that will solve the adhesion problem. The foam goes on in two hours from now, I'll report our findings.

It is closed cell foam, too.

oG

Gerry Wagoner

Posted: Nov 28, 2008 09:48 AM

Feel free to email me FoamRun and we can discuss the brand(s) of foam we are having this problem with.

Gerry Wagoner

Posted: Nov 28, 2008 01:59 PM

The experiment failed. After priming, this foam disbonded from the concrete surface just like the other batch.

Concrete surface temperature was 57° - 63° F.

Somebody better figure this out at the manufacturer level, and pronto.

oG

SprayFoamSupply.com

Posted: Nov 28, 2008 08:06 PM

Hey Gerry,

What was the pass thickness that you sprayed?

George

Posted: Nov 28, 2008 09:26 PM

look at your batch number for the resin,,
try another lot,,,sounds like the environmental conditions were well in order,,and i am confident of your processing skills,,so i would be suspicious of a lot that just aint workin the way it should,,,use it for wall foam,,it will stick fine,,concrete bites,,,(figuratively)or have your supplier exchange it for a different number,,,
sometimes one number will perform better than another,,,particularly in suspect substrates..
we are only as good as our products manufacuturers,,,(i tell em to add more of the sticky stuff and they just look at me like im a moron or sumpin!!!)
and george is thinkin...dont hog it,,,shine the first pass,,1/2" or less and then build on the shine,,,keep the temps down as low as you can so as to still allow good impingement and blend and thus foam production,,but low enough to reduce the thermal shock/shear at the substrate to foam interface,,,(keep the temp swing as low as you can)plan on 20-30% more material for the shine and build,,,pending on the profile of the foundation...
good luck ger..
'dude

Posted: Nov 29, 2008 09:32 AM

Foamdude,
when you say "shine", are you referring to the look of the slow reaction from quicker passes on concrete? if so, how fast do you build onto that pass? would you wait for it to react (10-15 seconds)? like using the "shiny" pass to help warm the concrete?
As far as temps, how low can you go? i know each situation/foam is different, but how low have you let the A & B get?
I usually spray my pass at one time with good results, but this has happened to me in a crawl space once. and i had to scrape it off and redo.

-aaron

Bryan Kwater

Posted: Nov 29, 2008 09:50 AM

We have also had this same problem recently. Luckily it was just on a fairly small area. We were trying to spray between 1/2" and 1" in one pass. Ass soon as the foam cooled (approx. 10 minutes) an area approx. 4'x10' would pop off. We had the problem as soon as we started spraying a crawlspace.

What ended up working for us was to put a flash coat as thin as possible and let it sit for 10 minutes or so. Then when we applied the rest of the foam at 1" thick, we had no bonding problems.

The block walls looked dry before we sprayed and the block was about 50 degrees. The causes could have been that the blocks sweated when the foam heated it up, or that there was some sort of residue on it. Every crawlspace that we have sprayed since then has not been a problem with the flashcoat being sprayed first.

Gerry Wagoner

Posted: Nov 29, 2008 10:24 PM

The pass was 1" and 1.5"

oG

Gerry Wagoner

Posted: Nov 29, 2008 10:27 PM

I believe that Dylan tried a flashcoat last week and that failed as well. I'll review with him Monday morn.

og out

Glenn Gamblin

Posted: Dec 10, 2008 10:29 AM

I have had similar experiences in the past when spraying concrete, and thick steel as well. The only fix that I found is to use a forced air heater to heat it up a bit extra, because the thicker material draws so much heat from the foam. I might be completely wrong here, but I have never had the foam turn loose from warm concrete so im sticking with it.

Gerry Wagoner

Posted: Dec 10, 2008 12:23 PM

Was that a pun?

Glenn Gamblin

Posted: Dec 11, 2008 08:46 PM

I do believe so!

Brian Currie

Posted: Jan 15, 2009 09:21 AM

I have sprayed alot ot foundations cold,wet, hot whatever and never had any problems.I truly think it is the Permax that makes the difference

Posted: Mar 23, 2009 08:13 PM

I have noticed this with walls as well, but only when I totally fill the whole stud area with foam. If I spray a light cote first and then come back later it doesn't seem to happen.

Dennis Davidson

Posted: Mar 24, 2009 10:08 AM

We've had the same problem before too.
It's not the foam (rarely is) and you should never apply a thin 1/4"-1/2" layer on a cool surface either. This can set you up for a failure too.
Try spraying a 4-5' pass, 1-2" thick, then skip a pass, do the next one and skip one. I know, sounds like dancing. Later ( 1/2 hour to an hour?) go back and fill in the gaps. Haven't had any problems doing it this way.

Posted: Apr 06, 2009 09:48 PM

whos foam was it that popped of the concrete deck? It was not a BASF Blend was it?

Posted: Apr 07, 2009 05:52 AM

(you mean it could be product variation from lot to lot??? damn,,,,,)

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