I asked Drew to talk about building the base/subfloor for one's travel trailer (there are many approaches, as we discuss in the Tumbleweed Tiny House Workshops I teach) and here's what he had to say...
One of the most talked about subject in tiny house building is the subfloor.
Like a number of subjects surrounding the building of a tiny house, there is no black or white; right or wrong. It truly is left up to the builder and his perceived version of what will work within his skillset (or pocketbook).
Once a trailer has been chosen (as ours was sometime ago) it quickly becomes time to decide just how the house will stay attached. That, my friends, is where the subfloor comes in.
Because we chose to use an EcoFoil radiant barrier we knew that would be one of our first steps. It wasn't THE first step though. We essentially ran a stringer down the center of the trailer in between each cross beam. This will serve as extra structural support as well as a way to hold in the insulation. Once we had the blanket of double bubble radiant barrier on the frame we added our floor joists. Each joist was constructed of 2"x4" lumber and held in place two ways.
1) If the joist fell directly on a metal cross beam it was attached by a 4 1/2" carriage bolt that is countersunk through the wood and then down through the metal, going through the EcoFoil and then tightened up by a washer and bolt.
2) If the joist did not fall directly on a metal cross beam it was attached via joist hanger which was attached by nail to the perimeter framing.
After our joists were in place and bolted down we then wrapped our remaining EcoFoil around the framing, stapled it into place, and prepared for the subfloor. Our subfloor is LP ProStruct Floor with SmartFinish - a durable overlay of beautiful, professional-grade substrate With no knots or voids. The subfloor is held into place by a bead of construction adhesive on all exposed joists and then 3 1/2" framing nails around the top perimeter of the 4'x8' sheets of sub.
Now that I read back over what we did I realize in words it isn't all that complicated. And I guess it wasn't. It is time consuming though and presents hours of questioning yourself, your skills, and the whole dern tiny house! But as I said earlier, there is probably as many ways to construct a tiny house floor "sandwich" as there are tiny houses. What it truly boils down to is being comfortable with your own finished product.
If you want to see the visual of how we constructed our floor I invite you to watch our video here: http://youtube/9I--d6xB_II
While you're on YouTube feel free to subscribe to our channel!
