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eric s Posted: Oct 03, 2014 10:53 AM	Recent Spray Foam Shrinkage Hello, I was hoping to get some advice. 2 years ago I had my walk out basement spray foamed with Corbond MCS. It was sprayed on a very cold day in Nov. The job called for 3.5 inches but the young man that arrived on the job basically filled the 6x stud bays. Recently I've noticed some shrinking which has been pulling the studs away from window/door frames. The shrinkage varies from 1/4" to 1/2". Pictures are here: https://imageshack.com/a/BSPz/1/ Is this anything I should be concerned about? We are planning on drywalling this winter but now im concerned about closing up the wall. I've already cut the seam near the windows/doors to relieve some of the pressure. Any input would be appreciated. thanks
mason Posted: Oct 05, 2014 08:04 PM	The cracks should be filled in. Depending on how far the void goes, you may be able to fill it with a gap/crack filler single component polyurethane foam. I would also contact the contractor that installed your foam. They should correct the problem. Also, read my article on my website masonknowles.com on Troubleshooting SPF Applications.
mark moyer Posted: Oct 08, 2014 06:53 AM	look at your pix foam job looks great!! nice job!! that doesnt look like the foam shrunk,, it looks like the wood dried and shrank some notice the nice linear crack...not a concave type contraction normally seen with collapsing cells... yep,,,drying lumber,,, caulk the cracks with single component foam. every thing will be just fine. dont forget to caulk your "double studs" and other joined frameing members,,,you see,,,lumber does shrink,,it moves,,it expands and it contracts oh and lets not forget that plastic insulation materials need the appropriate thermal barrier covering when exposed to occupied space...
eric s Posted: Oct 09, 2014 01:13 PM	ok thanks for the feedback. I cut the seems adjacent to windows to relieve the pressure and have since used decking nails to retighten up the king/jack studs. I will fill the voids with either foam or caulking. I am due for a framing inspection this month for my basement reno so it will be covered up after that. since the sprayer overfilled I didn't necessarily want to get the contractor back involved if it wasn't an important issue as I do not want to get anyone in trouble.
SprayFoamSupply.com Posted: Oct 09, 2014 07:47 PM	I can't see the pics when I click the link.
eric s Posted: Oct 09, 2014 08:21 PM	Copy and paste the link .. Or if you are clicking on it you need to add : after the https. This site is removing it for some reason
mark moyer Posted: Oct 13, 2014 02:51 PM	so wadda ya think georgeous....
mark moyer Posted: Oct 17, 2014 09:42 PM	oh george... lol
SprayFoamSupply.com Posted: Nov 01, 2014 07:55 PM	Doesn't look bad to me. If the sprayer put 5" instead of 3", I would guess that he sprayed a little thick in his passes, or he sprayed it all at once. That would make the foam lighter density and a little prone to shrinkage. I do agree with the dude, that the space between the studs is very uniform and not uneven or sucked in more in the middle which is what I would expect to see if the foam was shrinking. Cut a slit down the foam bay and see if there is negative pressure in the foam and the slit opens up. If so, make some cuts in the foam to relieve the pressure then foam them in. George
eric s Posted: Nov 04, 2014 02:06 PM	hello thank you for the responses. They eased my mind. I have been relieving pressure by slicing between the foam and king studs of window/door frames. I have then been filling the small gaps with can spray foam - the window/door minimally expanding version. The installer did use multiple passes but im not sure how many. I did have to cut some away at one point for a drywall trimmer and It looked like the foam was very dense. One thing I forgot to mention is that Ive started to use a dehumidifier recently and I think that may be contributing to the lumber shrinkage as suggested. Thanks again for the replies.

Author

Comments

eric s

Posted: Oct 03, 2014 10:53 AM

Recent Spray Foam Shrinkage

Hello, I was hoping to get some advice.

2 years ago I had my walk out basement spray foamed with Corbond MCS. It was sprayed on a very cold day in Nov. The job called for 3.5 inches but the young man that arrived on the job basically filled the 6x stud bays.

Recently I've noticed some shrinking which has been pulling the studs away from window/door frames. The shrinkage varies from 1/4" to 1/2". Pictures are here: https://imageshack.com/a/BSPz/1/

Is this anything I should be concerned about? We are planning on drywalling this winter but now im concerned about closing up the wall. I've already cut the seam near the windows/doors to relieve some of the pressure. Any input would be appreciated. thanks

mason

Posted: Oct 05, 2014 08:04 PM

The cracks should be filled in. Depending on how far the void goes, you may be able to fill it with a gap/crack filler single component polyurethane foam. I would also contact the contractor that installed your foam. They should correct the problem.

Also, read my article on my website masonknowles.com on Troubleshooting SPF Applications.

mark moyer

Posted: Oct 08, 2014 06:53 AM

look at your pix
foam job looks great!! nice job!!
that doesnt look like the foam shrunk,,
it looks like the wood dried and shrank some
notice the nice linear crack...not a concave type contraction normally seen with collapsing cells...
yep,,,drying lumber,,,

caulk the cracks with single component foam.

every thing will be just fine.
dont forget to caulk your "double studs" and other joined frameing members,,,you see,,,lumber does shrink,,it moves,,it expands and it contracts

oh and lets not forget that plastic insulation materials need the appropriate thermal barrier covering when exposed to occupied space...

eric s

Posted: Oct 09, 2014 01:13 PM

ok thanks for the feedback.

I cut the seems adjacent to windows to relieve the pressure and have since used decking nails to retighten up the king/jack studs.

I will fill the voids with either foam or caulking. I am due for a framing inspection this month for my basement reno so it will be covered up after that.

since the sprayer overfilled I didn't necessarily want to get the contractor back involved if it wasn't an important issue as I do not want to get anyone in trouble.

SprayFoamSupply.com

Posted: Oct 09, 2014 07:47 PM

I can't see the pics when I click the link.

eric s

Posted: Oct 09, 2014 08:21 PM

Copy and paste the link .. Or if you are clicking on it you need to add : after the https. This site is removing it for some reason

mark moyer

Posted: Oct 13, 2014 02:51 PM

so wadda ya think georgeous....

mark moyer

Posted: Oct 17, 2014 09:42 PM

oh george...
lol

SprayFoamSupply.com

Posted: Nov 01, 2014 07:55 PM

Doesn't look bad to me. If the sprayer put 5" instead of 3", I would guess that he sprayed a little thick in his passes, or he sprayed it all at once. That would make the foam lighter density and a little prone to shrinkage. I do agree with the dude, that the space between the studs is very uniform and not uneven or sucked in more in the middle which is what I would expect to see if the foam was shrinking. Cut a slit down the foam bay and see if there is negative pressure in the foam and the slit opens up. If so, make some cuts in the foam to relieve the pressure then foam them in.

George

eric s

Posted: Nov 04, 2014 02:06 PM

hello thank you for the responses. They eased my mind. I have been relieving pressure by slicing between the foam and king studs of window/door frames. I have then been filling the small gaps with can spray foam - the window/door minimally expanding version.

The installer did use multiple passes but im not sure how many. I did have to cut some away at one point for a drywall trimmer and It looked like the foam was very dense.

One thing I forgot to mention is that Ive started to use a dehumidifier recently and I think that may be contributing to the lumber shrinkage as suggested.

Thanks again for the replies.

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