I have a large carport about 20 feet wide. It has 2X8's spaced 2' apart with
2X4's crossing them at 4' intervals. The tin is regular corrugated roofing
and is on top of the 2X4's. Problem is the nails are all coming up. They are
aluminum nails with a rubber washer. I need to get on top of the tin to
repair it. Was thinking of putting some 1/2" plywood on top of the tin and
trying to walk on it. Then I decided to ask and avoid a neck breaking
experience

For what it's worth, on the bottom of the 2X8 rafters are some 2X4's nailed
to keep the 2X8's from twisting?? I guess that's why there are there. They
are on 8' centers, the highest one is just over 10' off the ground. Was
thinking of trying to prop up a few of the 2X8's using the 2X4's as stops to
hold the top of the prop and just wedging the other end into the ground. The
2X8's are supported at one end by the building and at the other by some 4X4
posts with two 2X8's bolted together running between them. Seems stout. The
2X4's under the tin are worrying me.

So, what do I do? And, what do I replace the nails with?

Al