Glue everything, set the top on and staple it, then cut all the plumbing holes. Cut outs for the fenders as well. Each section has a 1/2" tongue the next section will slide into for support and joining. The old floor was pure styrofoam with 1/8" wood on both sides, making it a total of 1-7/8" thick. I used 3/8" outdoor siding on the bottom, and 3/4" floor type plywood for the the top. Each stud or joist had to be cut on the table saw to give me the proper thickness floor. The bottom has 7 coats of exterior latex paint. I did not sheath it but probably should have. The exterior siding and 7 coats of paint should last a few years any way.
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Glue everything, set the top on and staple it, then cut all the plumbing holes. Cut outs for the fenders as well. Each section has a 1/2" tongue the next section will slide into for support and joining. The old floor was pure styrofoam with 1/8" wood on both sides, making it a total of 1-7/8" thick. I used 3/8" outdoor siding on the bottom, and 3/4" floor type plywood for the the top. Each stud or joist had to be cut on the table saw to give me the proper thickness floor. The bottom has 7 coats of exterior latex paint. I did not sheath it but probably should have. The exterior siding and 7 coats of paint should last a few years any way.