Is it possible to repair a SIP roof that is rotting?
We built an SIP home using panels from ACH Foam Technologies. The roof was installed according to manufacturers specks. The panels were OSB on both sides of expanded polystyrene insulation, about 7″ thick. Block splines were installed with the prescribed Do All Ply sealant. This design had space between the lines of calk for air to move vertically. The OSB has begun to de-laminate at the seams visibly under the shingles. It is obvious that moist air is moving from the interior, especially during the winter, up along the seams and condensing on the undersides of the roofing tar paper and asphalt shingles. Roofing nails have let go. It is an 8/12 or a 12/12 pitch roof. Too steep to walk on. The panels are about 15′ long ranging from 3′ to 6′ wide
Has anyone come up with a plan to repair a situation like this. Somehow the leaks in the splines have to be addressed if such a thing is possible before a repair would even be feasible. Can the rotten osb be cleanly removed? can new osb or plywood be effectively applied and glued? Is the roof structurally safe to work on. Would it be less expensive and labor intensive to remove the panels with a crane and install a new roof?
A spot inspection at the bottom, middle and ridge have revealed that the osb has deteriorated and de- laminated most near the seams.
I would greatly appreciate any help and useful information I can get on this issue. Thanks
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