Tongue-and-groove siding joints
I’m hoping to install some 6in cedar tongue-and-groove siding horizontally over vertical Rainvent battens next week. As my boards are all 10 ft long I will need three to four pieces to span the long edge of the house and will therefore have oodles of joints. It seems the standard here is a 45 degree bevel join (scarf joint?). I will treat all cuts with the same semi-transparent stain I’ve used to pre stain all the boards. Questions:
1. Should these joints between adjacent pieces of siding be caulked or glued? I’ve seen people on this forum recommend metal flashing behind the joints instead, but I’m not sure how that would work with tongue-and-groove boards.
2. For the anti-caulk contingent: what of siding to trim and trim to window joints?
3. Caulk or not, should butt joints like those between siding and trim be afforded an expansion gap?
4. Does anyone have reasons for or against running trim over siding verse butting siding to trim assuming critical areas like window heads are afforded a metal flashing?
I’ve attached a photo of the siding-siding joint mocked up with some of my stained test pieces. It all fits together pretty snug.
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