Placing windows and doors
Product performance. In an average new home with average windows, the windows contribute more to that home's heating and cooling requirements than the entire wall surface area. Since typical R-2 windows and wood doors have about 1/12 the insulating value of a good SIP wall, SIP buyers are strongly encouraged to purchase substantially better windows and doors to compliment the comfort and energy-savings benefits inherent in SIP products. Shoot for windows with good NFRC U-values ratings (U-0.35 or lower in moderately cold climates) and low solar heat gain coefficients in cooling climates (SHGC = 0.40 or lower).
Installation. In all but the driest of US climates, the most important detail with window and door installation is installation of a drainage plane surrounding the exterior of each unit. A drainage plane's purpose is to drain away water that may get past the first line of defense-caulking-around windows and doors. The goal is to avoid moisture damage to the SIP frame to which the window or door unit is attached.
The attached detail, which incorporates overlapping materials to achieve drainage, is excerpted from the Builder's Guide for Cold Climates (available from http://www.eeba.org/). The book is highly recommended, as it provides the best building details for avoiding moisture problems in today's new SIP home. The book also includes sound explanations for why such details are necessary.
Once you have installed the window and/or door for proper functioning and protected it with a drainage plane, you should air-seal between the unit frame and rough opening. This can be achieved with a combination of foam backer rods and either non- or low-expansive foams. Don't use fiberglass; it slows down but does not stop air movement. Also avoid any use of highly expansive foams in these locations, as they can impede proper opening and closing of the units, even breaking glass in the most extreme situations. (Also, see Air Sealing section.)