Installing vinyl windows
I’m at the point of installing new construction vinyl windows in my house and I am uncertain about two aspects of the installation.
1) Caulk behind the window fins; yes on no ?
The manufacturer says yes, but in an article on BuildingScience.com, it states that it is “unnecessary and dumb”.
With proper flashing, it does seem kind of redundant; sort of like wearing a belt with suspenders.
What say ye ?
2) Nail the fins tight or nail loose like vinyl siding ?
The manufacturer say loose to allow for expansion, but even when nailed loose, I wonder how the vinyl can expand and contract given the orientation of the nail slots. In other words, the side fins have vertical slots, supposedly to allow vertical expansion of the window, however, the top and bottom fins have horizontal slots which would seem to interfere with the vertical movement of the window.
The same could be said about the horizontal movement of the window. (Top/bottom slots inhibit vertical movement; side slots inhibit horizontal movement)
What say ye to this ?
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