Foundation Construction Link (Part 1): https://www.backyardchickens.com/forum/viewtopic.php?id=280847 Roof Construction Link (Part 2): https://www.backyardchickens.com/forum/viewtopic.php?id=283795 Nesting Boxes for the Chicken McMansion (Part 4) https://www.backyardchickens.com/forum/viewtopic.php?id=284067 Windows for the Chicken McMansion (Part 5) https://www.backyardchickens.com/forum/viewtopic.php?id=285527 Roosts for the Chicken McMansion (Part 6) https://www.backyardchickens.com/forum/viewtopic.php?id=287385 Rainwater Collection System Construction (Part 7) https://www.backyardchickens.com/forum/viewtopic.php?id=290206 This is the third part in my little series on building the Chicken McMansion. I have looked at dozens of coops here and other places and tried to incorporate all of the lessons that people have learned before me, and to incorporate some of the building skills I have picked up over the years. My design criteria were 1. Must be wind proof. 2. Must be varmint and critter proof 3. Must be quiet. (We are in a residential neighborhood so the less noise, the better) The two links above show you how we got to the point I am beginning at. Please review those threads to see how the foundation and roof went. The first step was to install four 2x4 timbers around the perimeter of the base. There is 2 feet of clearance between the bottom of the 2x4 and the top of the foundation timbers. Lots of room for the girls to run. I used 8 galvanized corner brackets secured with 1 5/8" Gold Screws to mount these 2x4s. I used my chop saw to make sure they were cut very accurately, and then screwed them all into place once I ensured everything was level. The floor of the coop is of course going to be exposed to a lifetime of chicken poop, and I am concerned about the floor rotting out eventually. The solution was pretty simple. I added a couple more framing 2x4s, and then cut a pair of pieces of Hardi-Backer board to fit. Hardi-backer is used for any application that will be wet, especially in showers as a base for ceramic tile. It is impermeable to water. It cannot rot. It is ideal for this application, and I plan on painting it with a 1-part epoxy paint. This will be a 100 year coop... Next, I added a 2x6 footer all the way around the edge of the floor, but leaving the side facing the cleanout open. I put down a bead of polyurethane based adhesive, clamped the 2x6 in place with a heavy bar clamp, and then secured both ends with several heavy construction screws. There is a method to my madness... Next it was time for framing. I am building two large nesting boxes that will be attached to the outside of the coop, so I am framing for them now. I used 2x4 framing for the large lower opening (nest box) and then switched to lighter 2x2 framing for the windows above. All of it was again secured in position with my nailgun and 2" galvanized wire nails, and then I went back and pre-drilled holes in the structural 2x2's and secured them with gold screws as well. One of the most common comments I have seen about first-time coops is "I wish I would have insulated it". I am doing exactly that. I am using 1 1/2" foam block insulation. This material is mold resistant, and does not contain hazardous chemicals like formaldehyde. It is very strong, and easy to cut with a box knife. I got the smaller pieces at the Home Center because they were easier to deal with than the much larger pieces they also carry. I started with the ceiling over the coop. I cut the blocks to fit, and they pressed in very nicely. I installed the insulation level with the bottom of the roof joists, and left a substantial airspace between the bottom of the polycarbonate roofing and the top of the insulation. this will allow the roof to breath in hot weather and will prevent warping, while reducing the heat transfer in to the top of the coop. Once the ceiling was insulated, I cut 3/8" plywood to cover the whole ceiling. I screwed it in with 1 5/8" Gold Screws.