by Wolffarmer » Wed Feb 23, 2011 1:09 am
30 inch wide works good for me. I took my width from the house door I use most often. 36 inch high sounds ok also. Kind of depends on how much side wall strength you need. When I framed up my wall and door opening I put oak in for the hinges. Probably over kill and it did add weight. I cut the opening for the door before I started to frame it up. then I framed wall and door separately, leaving a bit sticking out and used a trim router bit to cut off the excess of framing material hanging out. It worked for me. For ply I used 3/8 outside and 1/8 inside with 1 inch thick spars. Sounds like your ply is thicker so your walls should be plenty strong. Mine are plenty good.
From your description it sounds like you are going to put the 1x3 in the wall and seal the wall up and then cut it out. Hoping to hit the near center of the 1x3. Works for me if I could plan that well
Randy
"these guys must be afraid of the dark"