We began framing the floor. It involves sealing up the underside of the trailer for insulation and to prevent damage from moisture and pests, as well as creating a way to attach the entire structure to the trailer.
Before we had started any work at all, our good friends Jonas and Isolde + family came to visit us from California. This was excellent timing because Jonas is a brilliant contractor/do-everything guy and Mr. Hart got to pick his brain a little. (And Isolde is a perfect balance between creative + practical so she and I talked a lot about the floor plan, which is way more fun than floor framing…but that comes later).
Mr. Hart spent some time with Jonas, telling him all about our plans. Jonas walked around the trailer a couple of times listening to Joel talk, and then proceeded to list off some ingenious suggestions that changed all of the plans, which are directly reflected in the way we did all of what follows. Thank you Jonas!
First we needed to figure out a way to hold the insulation in that would keep it protected from moisture if traveling in damp conditions, as well as from mice and other pests. We considered using a thin wood, but that would require lots of work priming and painting it in order to make it waterproof. Jonas suggested using FRP panels (fiberglass reinforced panels), the bumpy stuff they use on commercial bathroom walls, which is ideal because they are thin, light and waterproof. Although we are trying to minimize our use of petroleum products, synthetics, plastics, resins, and the like, we thought this was a place that was worth the trade-off.
We decided using pressure treated wood for the floor framing wouldn’t be necessary, since we’re not building a structure that will have any sort of direct moisture contact, or contact with the ground or concrete. Also, we realized that pressure treated wood tends to be lower grade, softer species. Number 2 grade doug fir will last longer than softer grade pressure treated and there will be no chemicals such as would be involved with using pressure treated wood. It just seemed even more unnecessary since we were planning to make the entire bottom fairly waterproof anyway.
The house will be secured to the trailer in several ways. What Mr. Hart just finished are the blocks that were spaced every couple of feet in the channels that run the length of the sides of the trailer. These secure the 2×6’s that run lengthwise and cap off that c-channel rail on both sides.
Next the floor joists were placed on the trailer, and they are screwed into the blocking and later bolted in three spots. They are secured with the bolts on each side of the trailer through the 2×6’s and they will be bolted through the metal brackets which were welded onto the trailer and run down the center of the trailer.