EASY COOPS Chicken Coop Plan 3x6 Assembly Instructions Manual page 11

STEP 8
Install Plywood for the Roof
8.1 Cut sheet of 5/8˝ plywood for the roof sheathing using the drawing below as a guide.
You will need two 1´-11˝ x 3´-6˝ sheets.
8.2 Secure the plywood with 2˝ wood screws.