Replace window with New Construction window

sidingwindows

I am looking to replace some windows. The current ones are quite old and the wood trim/etc around the windows are decent..but a low decent. (not great). Now I do know I could just replace them with the 'pocket' or 'builders' version which uses the existing trim and just fits in place. My only concern is that the windows and trim is not the greatest and I don't trust that those are in good enough shape to keep.

Now the question is if I replaced it with a new construction, what would I have to do to install them without needing to replace siding? My Concern is if I replace the windows, they will be too small that I will need to add siding to fit them into their previous opening.

Best Answer

You almost certainly can't use New Construction windows without at least removing some siding. This type of window is intended to be installed before the siding is on, so you can integrate its built-in flange with the wall's water-resistive barrier (tar paper or Tyvek housewrap, usually) using tape and good lapping, all of which requires several inches of space on all sides to work. If you're not planning to remove the siding to expose your wall's WRB, then there is no advantage to using a new construction window.

With Replacement windows, you can order them in whatever size you want, so getting a window that's too small shouldn't be a concern.