housewrap without removing siding

Question

I'm adding an ADU in an old shop building that is sided with quarter-sawn tongue and groove siding. I really would prefer not to remove the siding, but I would like to seal the gaps between the T&G siding before insulating. If I had removed the siding I'd definitely housewrap it, but I'm wondering if there's a workaround for sealing the gaps from the inside of the unit prior to insulating? What's the best practice for making it weather tight?

It's framed on 24" so it's not as bad as it could be as far as working space between the stud bays.

Answer 1

We use housewrap because we know the exterior siding will leak.

If your building is NOT leaking now, then adding insulation will not create it to start leaking. Does the inside of the wood frame wall show signs of leaking? Are there dark stains at the joints of the sheathing that would indicate leaking?

In order to insure that you have adequate housewrap you’ll need to either 1) remove portions of the exterior siding at various locations around the building to verify that the existing housewrap is adequate, or 2) remove the existing siding and install new housewrap (or if there isn’t any existing housewrap then you could install new housewrap over the existing siding.)