The SIP walls near completion

This post comes to you from Al Cobb. I want to thank David Peabody for the opportunity to provide my input as this amazing project takes shape.

The PanelWright’s crew is preparing the third floor deck for sheathing today and will be completing the last of the wall SIPs tomorrow. This project should see a completed roof in about two weeks. Our crew will install the outsulation and set all windows and doors in preparation for the blower door test.

The overriding concern that our crew has during this entire build is to keep the envelope airtight. Panelwrights is contractually obligated to deliver a complete envelope that meets the Passive House standard. In my twenty two years of working with SIPs, I’ve seen some very tight houses. The average SIP structure that is properly installed will usually hit a range of .5-1.5 ach@50. (Conventional construction will often be in the range of 4-7ach@50) The tightest house I’ve ever seen tested reported a stunning .2air changes per hour during the test.

Attached pictures with following captions:

118: Last of floor joists installed at third floor

119: The tight site forced the PanelWrights crew to shuttle all SIPs in on a small trailer. This is the last load of wall panels.

128: This is the west wall and you should note the separation of the floors is evident by only the edge of the ¾” sheathing. This look is accomplished by hanging the floor system from the top of the wall SIPs. This design detail eliminates the terribly leaky platform framed floors you see in most conventionally framed houses.

120: The hanging floor system seen from the inside. Notice the top-mount hangers hold the I-joist floor beams to the inside of the insulating envelope.


Al Cobb
PanelWrights LLC