Should I wait to trim my windows?

[manu258]

I'm going to be replacing my old metal windows in the next year or so but I'm wanting to go ahead and install a sill and some casing. My question is, will I have to rip out my sill and the trim attached when the new window is installed? In other words, will the size of the new window fit a lot different than the old causing my stool's depth to be resized?

[Windows on Washington]

I would trim it out after you set the window. Are you going to be setting the new unit stud to stud? What is the exterior trim interface like?

[TheWindowNerd]

I would wait to replace the stools and do any additional trim work after the new windows are installed.

theWindowNerd.

[Guy]

Totally agree with those above. Do your replacements at the same time your windows are installed. This way you get a better result. I'd hate to see you doing it twice. Good Luck!!!

[robertrule]

I would prefer to wait for installation of new windows.