How do I make extension jambs for uneven sheetrock?

Question

Hello-
Please lend your expertise. I had new Ansersen 400 series DH windows installed in my 125 year old house. Where the windows sit at an even depth around the sheetrock I can just make extension jambs to bring them flush with the sheetrock and install the casing. My problem is on the windows where the jambs vary as much as 3/8". Near the top of the window it might be set 1/8" below the sheetrock and taper to 1/2" under the sheetrock on the bottom.
What's the best way to do this? I have a few thoughts, which work best? Is something else better?
1. Install extensions that are all beyond the SR and either plane, router, or belt sand them down, which is best? What happens to the brads used to hold the extensions in this case? Do they get planed also?
2. Put a series of varying depth extensions and fill in the gaps between them and the casing later with wood filler or caulk?

What's best here?
Thanks!

Answer 1

Measure the top and bottom sizes. Transfer these measurements to a piece of wood cut to the length you need. Draw a line between the two points and cut with a saw. Plane or sand edge to remove roughness. Now nail into place.



This will take some time, but I think you will be happy with the results.

Answer 2

By saying jamb, you means reveal right? --->http://toolboxes.flexiblelearning.net.au/demosites/series10/10_01/content/bcgbc4010a/13_cladding_systems/05_installing_windows/images/page_006_aluminium_frames.gif



And when you say >>Near the top of the window it might be set 1/8" below the sheetrock and taper to 1/2" under the sheetrock on the bottom<< Do you mean ((1/2" BELOW the sheetrock)) You really aren't making a lot of sense sorry.

Answer 3

if I understand you correctly you want to install a window at a angle to keep the distance between the finished wall and the window even? I don't think your being clear enough at least not for me.