Window Sill and Trim Dilemma
I am trying to figure out the detail for a thin window trim (aka Picture Frame style) using 3/4″ thick larch with the windows inset (refer to photo – ignore fact that there is no flashing).
On the outside of the 2X6 framing is 3-3/4″ of total depth (adding up the Zip-system; 2-way strapping; and vertical (larch) T&G siding.
I’ve been told that it is essential to have a slope to the 2X6 framing sill. My first detail (attached, showing a fixed window frame) has a flat sill with the wood sill extension set on the outside. A builder friend didn’t like this detail because there was not enough solid material to nail the sill (and, as per the photo) we don’t want to see any nails/screws
He suggested creating a wood sill that tucked under the window frame and a rabbit joint having the window and sill epoxied together t0 form a single unit (refer to attached detail – showing a casement window frame). Besides being finicky shaping the wood, the casement window has only 3/4″ of frame below the operable window to set the window into the rabbit.
(Note: these particular windows get installed from the inside)
Not sure what to do – any advise would be greatly appreciated!
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