One of the most talked about subject in tiny house building is the subfloor. Once a trailer has been chosen it quickly becomes time to decide just how the house will stay attached. And that 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 ran essentially a string down the center of the trailer in between each cross beam. This serves 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.
And because I am not very adept at verbally describing things, here is our latest video on our tiny house construction.
We also encourage you to visit us on Flickr and see our expansive collection of still photos!
Another great video, do you have footage or photo’s of how you attached the floor joists to the frame?
Thank you so much Andy. Please do share with anyone you think would be interested! We don’t have any video to speak of as it was dark underneath the trailer once we had the EcoFoil on and it was difficult to do the work and operate the camera. Likewise on still pics. Although I do think some can be found here: http://www.flickr.com/photos/andrewodom/sets/72157629885578061/
The floor joists were placed directly onto the steel frame. There were holes pre-drilled in the metal. We drilled pilot holes up through the steel frame holes into our 2″x4″s. From there we used a countersink bit to drill down into our 2″x4″s. This allowed us to put a 4 1/2″ carriage bolt through the wood, through the metal, and through the EcoFoil. Those were then tightened down by a washer and nut on the underside of the metal.
Lookin good!!
Thank you ma’am. Thank you!
I checked out your flickr pics and your sub-floor is tight. It appears to be the best constructed sub-floor I’ve seen on any tiny house on a trailer. The insulation looks nice too.
Thank you so much Albrecht. We are doing our best to do it right the first time, you know? We have no time restraints so we are really able to take our time and get everything as solid as possible.
Did you already cut holes for your drains before insulating, or can you do that right through the floor and insulation later?
Well, we have a storage box on the front of our trailer. That is where we are running the plumbing out of the sink wall and then down to underneath the trailer. However, I don’t think there is any problem drilling your holes after the fact.