How do I install window trim around uneven drywall surrounding my newly installed windows?

the best way is to take the piece of casing hold it up onto the sides of the window with the disired jamb reveal (typically 1/4") and draw a line, next score this line with a sharp utility knife (this will prevent any further damage outside the casing area.

remove how as much as the wall you need untill you feel the the casing or trim will lay flat. a thick chisle pionted scraper or chisel works very well.

if the window jamb is sticking out past the wall. either you can cut down the jamb, a biscut joiner works well for this with a little bit of hand sawing at the corners or you can add a strip of wood (the thickness of the extended jamb past the wall)along the back of the casing flush with the edge with glue, clamp untill dry and sand the edge flush.

having uneven walls around window casing is a pain as i know the can cause your joints to appear gappy or the trim corners to be concaved/convexed

sometimes you will have to adjust your miters to a 44.5 deg, 45.5 deg, 46 deg, etc to acheive a tight fit when this happens.

extending the jamb either adds another stepped reavel or if you extend it flush it will be very hard to conceal the joint since some jambs have a radius edge. it most likey will crack along that joint/seam in a year.

How To Install Window Casing

Hello Larry,

The trim guys I see on jobs just beat the mess out of it with the claw of their hammers. It looks like madness and makes one heck of a mess, but after watching they take chunks out until it's flat enough at the window to fit tight and not have a huge joint at the wall. It's been done a lot, by a lot of different crews. Hope that helps.

Larry if I had uneven drywall I would hold molding in place and mark with pencil and cut some of the dry wall away with utility knife, After it is painted it will be hardly noticeable

Good Luck

You might have to make custom extension jambs out of wood and nail them to the window frame.

This is for a door, but the same idea

http://www.hammerzone.com/archives/finishcarp/casi...

I agree Mark, extend the frame work of the window shim the trim when you nail it and then chalk the outer edges.

this makes a nice finish.

you could try to pull the window in as you nail the trim to the window, do this after you nail the trim to the wall. if you think you can do it otherwise then you will figure it out