"benick" wrote:

I have 2x4's running the length and width of the 5th wheel, nailed
with concrete nails into asphalt, then the press board and plywood
screwed into the 2x4's where they meet the asphalt.

Why does it matter if water got under it ???

The wood would rot.
--

Mr Stanborough said he threw the device out of his back door, where ?within 30 seconds there was a pop, a big puff of smoke and it went 10ft in the air?.

http://tinyurl.com/lvvd94 or
http://technology.timesonline.co.uk/...S&attr=2015164