Dick;


To further our discussion on US components being used in US made SIPs, I have found the the following:

Steel coil is 33% recycled content, comes from 2 sources - Alabama & Georgia (both US made steel)

bead is US made by NOVA

Adhesive is US made BASF / Michigan


EPS foam is 100% virgin used in the panels, 7% is cut off in the routing process and is recyled "in plant" and used in foam packaging products

Chris, I have to say that it is very heartening to hear, and in my mind it makes a big difference. I have always believed that steel SIPs have great merit, and having an "American Made" sticker on them is just that much better. Technically, I still have some issues with steel tracks used for securing the steel SIPs to each other, but I think that even those problems can be solved.

Posted By Dick Mills on 25 May 2010 12:09 AM 
Technically, I still have some issues with steel tracks used for securing the steel SIPs to each other, but I think that even those problems can be solved.

Dick;

what is your concern regarding the steel track?

Dick;

this is info on one of the suppliers:

Severstal North America is the fourth largest steelmaker in the United States and specializes in the full range of the highest quality light flat rolled products.  Fully integrated operations are located in Michigan, Maryland, Ohio and West Virginia.  A new state-of-the-art electric arc furnace operation in Mississippi serves the growing demand for steel in the southeastern United States.  Severstal North America also has several joint ventures for the highest quality coated products.

Steel tracks transfer an enormous amount of thermal energy. I ran the calcs once, and (if memory serves) a 20 gauge steel track would transfer around 30 times as much thermal energy through the wall as an equivalent length of 2x would. So, you have two big heat fins, connected by a ring of highly thermally conductive tracks. The things one can do about it: Use stainless steel tracks (which is still pretty thermally conductive, but considerably less so), or use two 'L' brackets instead of a track, or use a material that is less thermally conductive.

You also need a break in the skin of the SIP between the inner and outer edge of wall panel to further reduce the amount of thermal energy passed through the 26 gauge skin where it bridges between the inner and outer skins.

See thermo track below ............. or you can split track as you mentioned , there is no themal transfer from skin to skin at joint, just solid foam T&G joint



TOP



BASE




DOOR & WINDOW

Looks promising... Are these what you use? What material do they use for a thermal break? Do you have a link to the specifications for these tracks?

And, I am aware that there is no transfer from one panel to the next, only at corners where a solid steel track is used to make the joint. Do you split the skin under the track to ensure that the 26 gauge steel doesn't transfer thermal energy?

Posted By Dick Mills on 25 May 2010 07:11 PM
Looks promising... Are these what you use? What material do they use for a thermal break? Do you have a link to the specifications for these tracks?

And, I am aware that there is no transfer from one panel to the next, only at corners where a solid steel track is used to make the joint. Do you split the skin under the track to ensure that the 26 gauge steel doesn't transfer thermal energy?

Dick;

we have used the thermo track before , it is an .060 aluminum with a resin break, mitered corners are used in areas where thermal transfer is an issue as shown below, but testing has shown that a " butt" corner is much stronger and is our preference, as strength for hurricane resistance is of more importance than thermal transfer, there is also a way to thermally break a butt corner too (split skin) , it is commonly done in cold storage buildings