Replies

1. 
   Shep | Oct 02, 2006 11:59pm | #1

   Set the window in the opening.

   Nail the flanges.

   Make a false sill, and install under the window, over the lower flange. I bevel the top edge a few degrees so it sheds water, and mill a drip groove on the bottom about 3/8" from the front. Depending on the siding you're using, you may want to cut a rabbet at the bottom back to have someplace to slide the siding into.

   If you're adding wider side and head casings, make the sill long enough to allow for the extra width. I still sometimes forget that one.

   I've been using a cellular PVC board for this kind of trim these days; either Azek or Koma are good. 5/4 makes a nice sill; if you want heavier, glue 2 pieces of 3/4 together with clear PVC cement.

   Glue all the joints together, and don't forget to properly flash the window OVER any new head casing.

2. 
   ruffmike | Oct 03, 2006 01:52am | #2

   Try a search for trex window sills.

   You rip a 2x4 at a slight angle and you get two pieces for sills

   Install after window is in.

   I did it on these windows, you can see the look in  this pic.

                               Mike

       Trust in God, but row away from the rocks.

   
1. 
   stevent1 | Oct 03, 2006 03:56am | #3

   I like Heart redwood for window trim.Rip a 2 X at 6' on both edges. I always make the window trim match the rest of the house.Chucklive, work, build, ...better with wood

3. 
   PatchogPhil | Oct 03, 2006 07:17am | #4

   Start reading here for a primer on trex sills.  Although  you just might want to read the whole thread.  You'll need a good day and then some,  but well worth the read.

   http://forums.taunton.com/tp-breaktime/messages?msg=67972.863