SIP Walls Rotting at Windows
Hi everyone, first time posting but have read many q/a from here. Hopefully I can get some advice about the problem I’ve found in our SIP home.
My fiancé and I bought a (1998) SIP house about 8 months ago. 7/16 osb with EPS and 2×6 framing between panels. We live in Northern Ohio (warm humid summers and cold wet winters). The house has a metal roof and was replaced due to a leak in 2006. This was the only disclosed information relating to water damage that we had.
About a month ago we started replacing a deck on our north wall and in the process of replacing the ledger drip cap we found rot underneath a lower window behind the housewrap (Tenneco Amowrap). Upon further inspection we determined the rot to extend above the window to a second floor window but no further. (This issue was found under every window in this house) The severity was full rot of the exterior sheathing extending below ad approx 5in beyond the sides. The housewrap was not tucked into the window frame but instead was laid over the nailing flange and then J channel nailed over that. No tape or anything else. This was the practice used on all the windows except for the lower window where we discovered the rot. In this instance it appears the window was removed and starter strips were placed under the nailing flange and overlapped the housewrap. As well as a drip cap placed over the window. We also noticed sections of rot were repaired around the door near the window and covered with felt. To make the repairs on this door would have required removing the siding along the window making them aware of the problem and thus the shoddy repair attempt.
Obviously I’m considering a non disclosure lawsuit should insurance fail to cover the repairs. But if neither work then I’m stuck taking on this issue myself. I’ve contacted the sip manufacturer insulspan and spoke with qa/plant manager. His recommendation is either stick frame replacement of damaged sections or attempt to piece in new osb. Couldn’t say much more without structural engineer, understandably. At this point I’m leaning on stick frame replacement and filling with foam panel. The other issue we found was that the interior seams were not taped and there is noticeable discoloration of the osb on the exterior side seams leading me to believe there is vapor condensing between the panels. The house is approx 40×40 with 5 panels per wall per floor. I joist construction running parallel to gable walls on second floor and perpendicular on first floor. 1/3 of house is on slab with open ceiling to 26’ roof peak, no second floor.
Short of gutting this entire house inside and out does anyone have good recommendations on what I can do to address these issues? Ps sorry for the novel, I wanted to provide as much detail upfront as I could.
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