Building a window sill

Nov 14, 2020 Last reply: 5 years ago 5 Replies

In my house I have some windows that have window sills and some that don't. Don't know why the builder only put them some places.



The dims of the other windows have as a sill are 4-1/2" x 5/8" thick. So I found a piece of lumber at Menards that did not require a table saw. The Dims were 4-1/2" x 1" thick. Cut it, installed it looks good.



I want to install another one in the front bedroom, I found a piece of MDF at Menards that measured 5/8" x 4.5" (exact match), but it was designed to be a replacement door Jam. I noticed that it had relief grooves in the back to allow it so sit flush when in place.



When I cam home that evening I felt under one of the original sills and the relief lines were there. They did use a door Jam ! The next window sill will be about 5 ft high, so I need to find a board that is smooth / finished on both sides.



Anyone know of a board like this from Menards and/or HD ? Or should I just buy the door jam and fill the groove with something that wont crack or fallout ?



Thanks Sid


5 ft high is one mighty window sill, doesn't it block the view? And one would think you'd use the same decorative wood on all so they look the same.

It's for an arched window above a set of normal windows.

Yes, by itself would be high !

On Sat, 14 Nov 2020 15:38:02 -0800 (PST), Sid 03 posted for all of us to digest...

The reliefs are to break the water tension should it get under the sill. What are you concerned about? That someone might see it? Don't worry you will be the one thinking about it. After a period of time you won't think about it either.

On the first one I filled the outermost (visible) relief with joint compound and sanded then primed. Can't even tell it was there. On the 2nd and 3rd Sills, I found some Jam stock at Menards that had reliefs that are very shallow, Maybe 1/8" wide and only about 1/16" deep. These would be hard to see. These I will just cut, sand and paint. So far so good, Thanks for asking Sid.

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