Steve wrote:
Hello. The windows in my Mom's house were just replaced. Apparently they had
to move the windows about 1/4" forward from where the previous windows were
... so on each window there's now about 0.25" space ...(between the sill and the window).

I asked the window person what to do about the void. He said to fill it with
a piece of wood so I'm attempting to do that. ...

My reply would be to the installer "you're not done yet".

The answer on the use of filler for such a fix is it's possible but not
a real good solution. Really need somebody to do it that has the
facility to fit pieces in. It's not too difficult but depends on what
one has for tools and skills???

Alternatively, the other solution is to replace the sills or remove them
and add the width necessary and then trim to fit when replacing.

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