replacing roof and decking

[melco_]

replacing my trailer epdm roof and decking. I am wondering if 3/8 ext. LUAN would be sufficient or do I need to look at other plywood. do not want to go back with OSB.

[cwit]

When I did my 5er I left the luan down and added 1/4 " right over it. This gave me a nice walk on roof. Mine was done because the staples were pulling out that held the plywood down. The second layer was glued and screwed.

[westend]

AFAIK, there is no exterior graded Luan sheet goods. It all has an interior compliant glue. As was stated, use an exterior grade 3/8" Plywood. It should be stamped "BCX" or similar. The first two letters are the grade of finish plies and the last denotes exterior grade. A surface filler is typically used on screw indentations and seams, that keeps the EPDM from resting into a crease or hole.

[enblethen]

Shop that did mine used 1/4 inch exterior plywood.
They then coated each joint with leveling compound.