Different designers will have their own way of doing things but with SIPs, I like to dimension from the outside edge to the outside edge.  In the design stage you will need to know the exact width of the SIP plus any fudge factor to minimize waste.  SIPs are available in various widths - not always divisible by 4.  Depends upon the type of material and the manufacturer.  Some SIPs may be 47-3/4" in width but when they go together for a long wall there may be some traveling.  If so, then one of the panels may have to be cut.  Some SIPs can be cut anywhere to make them fit.  Others may lose their tongue and groove connections if cut.

So, what SIP do you think you will use?   Installers who have used that brand can give you more info.  Also, check with the manufacturer about how to minimize waste.  Where will you be building.  If you are building in the southeast, I may be able to donate some time to help you.

Posted By Alton on 03 Feb 2013 07:24 PM

Different designers will have their own way of doing things but with SIPs, I like to dimension from the outside edge to the outside edge.  In the design stage you will need to know the exact width of the SIP plus any fudge factor to minimize waste.  SIPs are available in various widths - not always divisible by 4.  Depends upon the type of material and the manufacturer.  Some SIPs may be 47-3/4" in width but when they go together for a long wall there may be some traveling.  If so, then one of the panels may have to be cut.  Some SIPs can be cut anywhere to make them fit.  Others may lose their tongue and groove connections if cut.

So, what SIP do you think you will use?   Installers who have used that brand can give you more info.  Also, check with the manufacturer about how to minimize waste.  Where will you be building.  If you are building in the southeast, I may be able to donate some time to help you.

Posted By DAND on 04 Feb 2013 04:24 PM
Check out Thermacore out of Indiana. I used them and their staff was great help, especially Kelly. That girl knows her stuff, and she saved me a lot of headaches. My wall panels were up to 18 feet tall and 8 feet wide. All the openings were cut per the drawings, not one mistake, and walls were 6 inch while the roof was 8 inches. All the electrical races were installed and it was a snap for the electricians. I am designing another SIP/IMP(roof). My electrician and I decided to run the wires for the next house in the attic and down instead of in the floor and up. The first house went up in 5.5 days including installing all exterior doors, windows, house wrap, and 30#felt on the roof. DanD

Posted By DAND on 04 Feb 2013 04:46 PM
You can minimize problems with some SIP dimensions by expanding or contracting your foundation by a foot or so. I did that very thing when I built my SIP house. I had exactly ZERO waste, and all the panels fit exactly as they were designed; no on the job wankering about. DanD

Posted By DAND on 06 Feb 2013 11:48 AM
I do agree with Alton, better know the exact dimensions of the panels. I think metal panels are less forgiving than OSB (just my opinion). From high school geometry you will remember that a 1 degree mistake at 2 feet in length is almonst insignifiant but make a 40 foot run and see how much a 1 degree mistake makes. Be sure to have a lazer level straight foundation. As I understand it, to maintain level, the metal "C" chanel at the bottom may not touch the foundation all the way across, then the void between channel and foundation must be filled with foam.
I did not have any "travel" with my panels but we used straps and ratchets to pull them together, and an 8 pound sledge hammer was used to tap them tight.

Posted By cmkavala on 06 Feb 2013 05:14 PM

DAND,
having installed all types I can tell you that metal Sips are the most forgiving and do not require straps and rachets
They simply fit!

Posted By DAND on 07 Feb 2013 02:03 PM
Lbear, I don't deny MIP's fit well. I was using 8 foot wide SIP's and they are heavier than a metal panel so need some tapping. The 8' wide panels have some benefits like reducing the seams by a large margin, which reduces the possibility of air infiltration, and minimizes thermal bridging too. We foam insulated all the seams as well. The jumbo panels also reduce the materials to connect said panels(screws and foam) and it reduces labor when installing them. We did need a crane to set them in place and that was not cheap, so I'm sure the cost of the crane was more than the cost of the extra labor. And you do have some wiggle room with the tongue and groove + spline if you need it that you do not have with metal. And if you do have to rework a panel in the field wood is my choice. You cannot stretch a metal panel, but you can scab on a 2xby with wood.

Posted By DAND on 07 Feb 2013 02:03 PM
Lbear, I don't deny MIP's fit well. I was using 8 foot wide SIP's and they are heavier than a metal panel so need some tapping. The 8' wide panels have some benefits like reducing the seams by a large margin, which reduces the possibility of air infiltration, and minimizes thermal bridging too. We foam insulated all the seams as well. The jumbo panels also reduce the materials to connect said panels(screws and foam) and it reduces labor when installing them. We did need a crane to set them in place and that was not cheap, so I'm sure the cost of the crane was more than the cost of the extra labor. And you do have some wiggle room with the tongue and groove + spline if you need it that you do not have with metal. And if you do have to rework a panel in the field wood is my choice. You cannot stretch a metal panel, but you can scab on a 2xby with wood.

Posted By DAND on 07 Feb 2013 06:13 PM
Hey Chris, You said you would not use an 8-foot metal SIP, can you save me some struggles and tell me why? Is it because of weight, or some other problem with such a wide SIP? TY DD