Joints not foamed
Stevekry
| Posted in General Questions on
I am having a SIP house built and it is now at roof level.
I have just noticed they the contractor arranged by the SIP supplier has not been foaming the joints when joining SIP panels, he has acknowledged his mistake.
How serious a problem is this and what remedial action can now be taken.
Any advice greatly appreciated.
Regards
Steve
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Replies
Steve or Graham,
This is a serious problem. You need to contact the SIP manufacturer right away and get a manufacturer's representative on your job site to provide advice. If you can't negotiate an acceptable solution with your builder, you may also need to talk to a lawyer.
For more information on this topic, see Air sealing SIP seams.
Steve, it could be there isn't a problem--yet. Foaming of joints can happen towards the end of the entire assembly process, since it relies on the joint being fully assembled. The contractor drills holes at about 8" intervals through the joint spline (from both sides, if the SIP is thicker) and blows expanding spray foam into whatever crack remains between the foam of the panels.
Proper SIP assembly is critical and sealing has to be meticulous. Beyond foaming, there are steps involving adhesives, gaskets, and various tapes. If there is ANY doubt as to the competence of the installer, stop him immediately and follow Martin's advice.
Hello Martin and Andy, Thanks for your advice, the foaming of the joints should have taken place during construction, according to their spec, the reason why it didn't is another question.
The builder is now contacting the SIP manufacturer so I will wait and see the outcome of this before contacting them directly. Work has stopped on the project at the moment.
SIPS joints must also be TAPED, inside and outside. The foamed joints eventually crack and you get air leakage which can destroy the OSB. Use a high quality peel & stick acrylic tape.
And this is the reason we can't have nice SIPS!
I have also seen SIPS foamed in place after the installation, in a similar fashion as Andy described. This technique was years ago though, and we all know that SIP construction has come under much fire about seam air leakage.
I would recommend as Bob did also, make sure to tape every seam you can (easier said than done when a seam is to the inside.)