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Step 3: Attach the Tin

Lay the tin over the frame, lining it up for best centered fit. Optionally put a bead of silicone caulk along the top of wood where it will interface with the tin to better seal the panel from drafts. Fit the corrugated foam thingy between the tin and the wood on both corrugated ends, you will probably need to stretch it to fit properly. Using the Roofing nails or some short screws, secure one corner, double check alignment and the foam (it likes to move if you don't hold the panel down), then secure the diagonal opposite corner and end of its foam strip. Nail the other corners to secure the tin and foam, and then nail down every valley in the corrugated tin starting in the middle and securing the middle most valley each time. Going along the flat/long sides nail the tin every 6" or so also starting in the middle and dividing the distances until you get to about 6". This is to keep any slop from being propagated along to one corner where it becomes a large gap. Again, make sure the frame is on a flat surface for this, nailing while its not flat will give you a twisted frame (mine came out with a minor twist).