Advice for lack of rainscreen or proper flashing
I’m hoping to get some advice regarding my split entry house (circa 1990) in Eastern Canada that has no house wrap, tape or sealant of any kind. Wall assembly is (inside to out) 1/2″ GWB, poly v.b., 2×6 studs, 5/8″ OSB, 1/2″ EPS rigid foam (nailed with roofing nails and no tape anywhere), vinyl siding (no furring). The brickmould for the windows and doors rest against the insulation and are only flashed at the top, tied back to the insulation, not the OSB. I’ve been replacing windows as needed over the last 5 years and have noticed damage to the OSB and under the windows at each location. Also found many rusted nails that fasten the rigid insulation. I was younger and “less knowledgeable” than I am now about flashing and drainage planes, so I simply replaced the windows/door in the same fashion as previously.
However, I have learned since then and so with the last window I replaced I framed the rough opening with ½” plywood to match the thickness of the insulation and used peel and stick flashing from inside the RO all the way around the frame to the OSB. I also flashed the window flange to the OSB after the window was secured. Then the insulation was cut back and butted against the plywood frame over the flashing. I’m fairly confident of my installation for this one window, but the others I’ve replaced and remaining original windows and doors are worrisome.
I will be replacing 3 windows and 1 door this summer and wonder if I really need to worry about the existing or older installations in terms of the impact on long term structural damage. Do you think it would be wise to invest in a whole house removal of the siding, rigid insulation and windows in order to properly install the house wrap/drainage plane, insulation (probably go with 2″ rigid instead) and properly flash all windows and doors? Or do I simply repeat my flashing efforts during my remaining window/door replacements and hope that the existing OSB/rigid insulation plane will suffice for the long term?
Thanks in advance for your thoughts,
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