If drywall is compromised and insulation is soaked in multiple areas, time to consider serious repairs.
After removing the shingles, it was clear that plywood was rotten everywhere and repairs were neglected. Once the plywood is removed, structural damage was visible and everything needed to be reinforced. Doing the right thing when nobody is looking is a rule I follow for the sake of being a decent contractor.
New roof sheeting is 7/16 OSB boards that are treated on both sides for the moisture from inside and for the water from from outside. Not a big job but safety concern for always there. New plywood is secured onto the homemade roof trusses with a 1/4 inch gap in between for the expansion.
At this stage we are structurally in good shape. Safe to walk on the plywood without the concern of falling through. Next step is to install dripedge all around and synthetic underlayment as a second line of defense.
Starter strips are installed all around the edge to increase wind resistance and give it a straight cut finish all around. We can install the architectural shingles manually with a hammer since it’s a small area.
We provide complete roofing services for residential Pitched roofs, flat roofs, Siding/Soffit/Fascia, Eavestrough repairs, foundation crack repairs and roof snow and ice dam removal services in Ottawa and the surrounding region.
Ottawa Roof Siding Foundation Repair Blog 
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