EASY COOPS 4x12 Chicken Coop Plan Manual page 14

STEP 11
Framing The Side Walls
11.1 Using 1 1/2 " x 3 1/2 " pressure-treated material, cut two rough sills and two window
headers and attach them using the illustration below as a reference.
11.2 Secure the sills to the studs with 4x5" wood screws.