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Flashing new construction window in conrete foundation

I have new construction windows that are attached to a concrete foundation via the PT lumber used to frame the inside of the opening.

The windows are fine but the trim and part of the framing have rotted out and the flashing is non-existent. The builder used pressure treated lumber to frame the opening in the concrete, OSB to fir out the window opening and just some caulk around the trim.

Now its all just rotted away. I made a piece of flashing to protect the top of the window and attached it with silicone as a temporary measure.

My question is: How do you flash a window mounted in a concrete foundation so its water tight?

I'll try and resize the pictures so they can be attached.

Timothy Miller
Re: Flashing new construction window in conrete foundation

the "z" flashing for the top of the window should of been installed in wet concrete.. haha- Actually a renovating window that has no tabs (verses a new construction) vinyl clad window installed with a 50 year premium caulking would be better and if you trim the window with PVC trim no rottttttt

Re: Flashing new construction window in conrete foundation

precisely as just mentioned. lining the opening with vycor first also helps also setting hte pt further back in the opening can create protection.

your other option is to bring the window further out to the face of the foundations then remove the siding directly above so you can install flashing up under the siding. this only works however when the opening is right at the top of the foundation wall where the floor system creates the window header

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