The less you change in a remodel, the lower your cost. Although it may seem a minor thing to change the size of windows, it is important to remember that windows must be supported and that existing windows are part of the structure of the exterior wall that supports the roof. Changing the size of windows will involve additional work. Additional framing work will be necessary in any case. If you change to smaller windows, the additional cost will be somewhat less than changing to larger windows, but there will still be framing, drywall, window installation, and installation of trim. Changing to larger windows will also involve removal of drywall, removal and replacement of framing, and new framing, drywall, window installation, and installation of trim. If you keep windows the same size, you can simply remove the trim, replace the windows, and replace the trim.

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