Plans Released to SIP Manufacturers for Quote

You may recall our Preliminary SIP Mfg Evaluation in early December. After speaking with the various manufacturers about their basic process, product and market differentiators I owed them more detailed plans to give us a quote for the two homes. I just finished contacting the manufacturers and delivering the plans to each of them for quote.

PV Solar Panel Quote for 100K House

The plans spec out 2×6 framing on 24″ centers with bat insulation (R19 walls / R30 roof)  which is what Level 5 will be quoting for a baseline cost. If we were to go with stick framing we would most likely not use  traditional bat insulation methods. At the very least we would caulk and seal all joints prior to installing the insulation and at the most we would use a full spray foam or blow-in cellulose insulation. I would probably lean towards a hybrid system of spray foam in a half-inch space between the framing and exterior sheathing, with a more traditional and less expensive insulation in between the framing. More on these options later…

Marker Time – Indoor Air Quality (Materials)

While I was initially very excited about using SIPs for these homes, some doubts have crept in that I am looking forward to addressing in more detail with the manufacturers. One of the main issues is our party walls in Philadelphia that must achieve a 2 hour fire rating in between new homes. One and possibly even two layers of SIPs will most likely not solve this requirement. The other issues is how to support the roof panels. If an extensive beam or truss system is required it will increase our material costs, effect our interior appearance and increase the need for traditional framers on the jobsite. As we get farther away from a full SIP home and closer to a 50-50 hybrid of SIP and traditional framing I get less excited as I envision the cost savings from efficiency starting to deteriorate…

100K House SIPs Installation Flickr Photo Set

Lastly, I have received some conflicting opinions on SIP assembly, sealing and exterior cladding that I am hoping to clear up and educate the team further on as we are all fairly new to SIPs and have no personal experience with a SIP project in Philly.