Installation and sealing the roof, floor, door and paint

This next phase of development included the application of roof material. I had to make a decision as to whether or not to make a peaked roof. One of the people I consulted presented a strong case for me to build a peak to allow for drainage and prevent ponding of rainwater on the roof. But in the interest of convenience and expense, I chose to make the roof flat. As justification, I knew there were several means of removing the accumulated rainwater. I was advised to use an elastomeric paint used for mobile home roofs. The manufacturer guarantees the paint will resist water for up to 50 hours at a time. Tilting the trailer a bit allows the water to run off. Indeed, this would not work if the trailer were hitched up, or even have much of a load, but during construction, tipping it up seemed a good option for removing water. Certainly wiping the roof off with a squeegee, or parking it in strong sun would work as well.
During this phase of construction, you can also see from the pictures that I secured and sealed in the windows and door unit. I took some extra measures to make them waterproof, sealing the edges with elastomeric caulking. This keeps the windows and door from leaking whether the rain was falling from above while the trailer is stationary, and also remain watertight when rain and spray hit the seams from the front while driving in the rain as the trailer is moving forward.
The floor went in very easily. One 4x8 sheet of plywood covered much of the floor. A cutout was made for the motorcycle chock. The last strip was easily cut and secured. I took a liberty when applying the lower sides of the box. Very conveniently, the scrap pieces remaining from the roof sheets were the exact sizes needed for the lower sides. I simply screwed these into place on the frame to seal up the lower sides from the inside. Given the shape of the trailer frame and the wheel wells, I used a relatively large amount the waterproof caulk as filler and sealant. And although this was a shortcut that avoided custom cuts and shaping of the lower sides, it appeared highly cost-effective. It was certainly much easier than fabricating something from scratch.