How To: Installing The Floor and Subfloor of Your Campervan

Subfloor and Floor

There are a few ways to begin your buildout. Some like the top-down approach, cutting windows and vent fans first, then moving to walls and ending with the floor. For us, we know that the van’s first trip is contingent on getting a second row of seats in so that we can fit the entire Home On The Loose Crew in safely for the long drive down to Indian Creek for Thanksgiving 2016.

Brenda has been talking to the ever-helpful Barry up at Van Works in Fort Collins. We know that our floor has to be complete before we can add the seats. There is no way I am crawling around underneath our new seats trying to put down our vinyl floor. So, it’s floor first for this build.

We began with a layer of insulation. A van poses a unique challenge in that it is not a simple,
flat surface. There are numerous “peaks” and “valleys” that make up the bare floor once the factory subfloor has been removed. We sacrificed four of the cheap-o blue foam camping mats, cut them in strips with the utility knife and used spray adhesive to secure the strips in the “valleys”.

We cut a sheet of hardboard into six inch wide shims and placed these perpendicular to the blue foam and resting on the tops of the “peaks”. The space in between was filled with thin sheets of closed cell foam. If I was to do it again, I would probably source out a slightly thicker foam to go between the shims. As it stands, I had to put two layer in between the shims and it was time consuming to get it all sitting flat. All told, we have about 3/4″ of closed cell foam beneath our subfloor.

We went with the less expensive RTD Sheathing found at the local Home Depot. It is just a hair thicker than 1/2″. We used the factory subfloor as a template and jigsawed out the floor pieces. So, now, we are looking at 1.5″ of floor (insulation + plywood)


We reused the factory bolts and bolt/tiedown locations and added in about 18 galvanized 1/4″
bolts to help get the plywood seams to sit down (mostly) flat. The bolts were drilled up from under the van to ensure we didn’t drill through anything important. The bolts all have washers on top and below to distribute the load. The bolt heads were countersunk using a 5/8″ hole saw.

We finished off the subfloor layer by applying caulk and wood putty to the seams and bolt heads. We also coated all of the exposed bolts under the van with a healthy glop of caulk to
discourage water infiltration and rust formation. We sprayed expanding foam into the gap between the subfloor and the van wall. (I would NOT do the spray foam again. messy and we had to cut and stuff the foam back to get
the floor to lay flat. Grrr)



The final step in the floor was laying down the vinyl plank flooring. There was a style on sale at Home Depot, we bought four boxes and covered the entire floor of the van. It looks gorgeous!

Seats arrive tomorrow!

Trim was re-purposed from a step riser product, cut with a miter saw and attached with countersunk wood screws

(Note: This post was originally written on our old blog and moved over here for posterity)

See you out there!



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