a wrote:
I am planning on replacing a rotten wood window in our concrete
foundation.
I don't need the window to open so I was wondering if I could use 4
pieces of treated 1X8 to form a box that just slides into the opening
& fasten it with a couple of concrete screws. I would install a
glass stop on all 4 sides with 1/4 round then have a sealed triple
pane glass unit made up to fit & seal it in place with silicone.

Two questions:

Do I have to slope the lower sill to allow water to run off?

and

Is 1X8 stock good enough (or should I be using 2X8)?

Thanks

I would want the ability to open a vent of some kind, even if you don't
do it often.

If you choose not to offer a vent, then why not glass block? You can
even add a vent to them, good security and light.

Yes, you need to slope the lower sill no matter what you do.

--
Joseph Meehan

Dia duit