Has anyone had direct experience with a SIPs company for a complete residential project?
CASUDI
| Posted in Green Building Techniques on
I have started a dialog with Premier SIPs (because they are 130 miles close) and with Fischer SiPs because they are very responsive (2400 miles distant) ~ has anyone had experience with either of these companies? The project is a 1500 sf modern studio type guest house (remodel), a shed roof with 16′ at the high end. SIPs are planned for all the exterior walls and roof, traditional framing for the few interior walls? Love to hear about your real world experiences.
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I can answer some questions about SIPs. Two major things to lookout for is:
1 - Noise: SIPs are not good sound isolators. They attain around STC26 and that is not good (typical framed wall is STC 38). One has to decouple a SIP (resilient hat channels) in order to get better sound ratings. This adds labor and costs but SIP companies don't like to talk about STC ratings because SIPs are inherently bad when it comes to stopping exterior sound from coming in.
2 - Roof & Walls: SIPs require furring on the exterior to help keep them dry. DO NOT install a roof directly onto a SIP roof without creating an air channel/rain gap using 1" furring strips and then attaching another layer of OSB and then the finish roof. The walls need it also. Do a Google search on SIP ROT and the Alaskan study and you will see why SIPs need to have a drainage plane.
As far as Premier goes, they are national, I've heard good things about them. SIPs are fast, strong, attain decent R-Values (usually R-30), good air sealing (watch joints and windows), and provide little to no thermal bridging. The downsides is that they can rot and delaminate and require furring strips on the inside and out to help with drying and sound control. This will add some significant costs $$ to the SIPs.
This is very helpful, thank you Peter. I am at exactly at that point in time where I am trying to find all the "right" questions to ask the SIPs manufacturers. If you think of any others, please let me know?