install new window in old clapboard

i am looking to add a window to an existing clapboard wall. any suggestions/sources for how to properly flash window without having to remove surrounding clapboard? thanks!
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Replies
Depends on the window and the trim. What kind of outside trim will you have (what do the other windows have)?
Tough job but barely do-able. Once you have your claps cut use a recip saw to remove any nails back for 3 or 4 inches under the claps. I slide a piece of galvanized break metal under first and keep it between the felt and clapboards so I don't tear the felt or housewrap. Then I cut some break metal flashing in long strips maybe 4 inches wide. I usually use aluminum since it's easier to cut in place if I need to trim later. I stick a wonderbar in the space between the siding and wall and jiggle it back and forth to give me a little working room, then squeeze 2 or 3 stripes of poly caulking on the back of the aluminum and slide it under the claps and over the felt. Once it's in place I'll squeeze more caulk in if I can. I repeat the same procedure on top except that the flashing has to go under the felt instead of on top. Renail the claps and you're ready to trim.
You forgot to mention to prime the cut ends of the claps.
thanks!
thanks to florida and dan h., interesting thing about the claps is that there is no felt or sheathing, just claps on joists. given this maybe flashing is a moot point? welcome your thoughts.
Well, at the very minimum you want Z flashing at the top.