Depending on where you buy your new construction window, you may or may not get a screen along with it. This is solely upon the seller's discretion. Sills, on the other hand, are almost always a separate purchase.

Do window sills get replaced with new windows?

Window sills receive the brunt of the moisture from open windows, yet they are never replaced during the window replacement process. That is a job for a fine carpenter or contractor.

Do uPVC windows come with sills?

Your windowsill is separate to your uPVC windows therefore they are not included in your uPVC windows. The windowsill is part of the buildings structure and is necessary for keeping the window in place and improving the windows energy efficiency.