Sill
The bottom horizontal member of the window frame — the “floor” of the opening that sheds water outward.
What it means for you
The single most important part to keep dry. A rotted sill is the classic reason an honest installer calls for full-frame instead of an insert; setting a new window over a rotted sill just buries the problem.
Where you'll see it
In the “rotted sill” conversation and on any full-frame recommendation.
Related terms
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