Construction.  page 2

This is the bare bones trailer as brought home from Tractor Supply company.  This is a light weight utility trailer so weight concerns are a Must.  Total carrying capacity is for the entire trailer is 1500 lbs.  This is a trick I learned from doing marine upholstery: The flooring is 3/4 inch plywood painted on both sides with exterior enamel. I know this sounds a bit much, however it goes a long way for protection against water damage. The floor bottom that mates to the trailer is covered with galvanized metal sheet flashing to protect the wood floor from road debris and water spray. The last thing you want to do is to have to replace the floor.  Remember - Good foundations make for good building.  Spend some time and get it right here and it will pay off in the end.

The sub floor framing are 2″X3″s glued and screwed together.  Everything that will be exposed to weather or road spray gets painted.  Two sheets of flooring plywood are attached to the sub frame assembly and bolted to the trailer frame with the total area being 6′X8′.  1×2 strips are attached to receive the wall panels.  Notice that everything is glued with construction adhesive and screwed for added strength. if you look closely you can see the metal sheeting on the underside of the flooring.

Now for the wall panels. Lesson learned from previous camper: 1/2 plywood is overkill! I built the first like a tank using full 1X4’s and 2×4’s. This can be a very heavy. The 3/8 (3 ply) plywood sheeting is attached to the strips with adhesive and screws at all seams.  I am an advocate of using construction adhesives at all joints for added strength! The panels are strengthened by adding 1×2 strips at all joints and various intervals. Do not try to use plywood alone. It needs some additional strengthening! (See above thumbnails) Full 4X8 sheets are used for the sides. Each piece builds upon the one before adding rigidity and strength. Notice that I left the fenders on the trailer. I will box over them later. They will provide additional protection in case of road debris. 

The interior is completely insulated with ¾ closed cell foam insulation and covered with 1/8 in plywood. All insulation seams are sealed with foil tape.  An interior wall is installed with construction adhesive and finishing nails. Tip: leave the end panel for last during the construction phase - it helps when fitting the interior walls and ceiling panels. note the 1×2 strips mounted along sides and at the front.