E350 Homemade Campervan - Seeking Input

[rigertoflip]

I am just getting ready to start building out my interior. I have really struggled to figure out how to adapt paneling to floor and walls, all the while adding insulation and noise dampening. Thought I’d post my general approach to converting the van and hope some of you may stop or correct me if I’m about to screw up, or encourage me if I’m headed in the right direction.

My plan is to finish the interior in this order: Floor, Walls, Ceiling. For now I’ll post my plans for just the floor, then update this thread based on feedback I receive.

I’ll glue .25” thick strips of pressboard into the grooves of the floor to make it less “channeled”. On top of that I’ll put down a heavy duty vinyl floor. I guess I’ll have to look at the gaps in the channels after I lay in the pressboard and decide if I need to float in some kind of gap filler.

That’s my plan for my first step, wide open to feedback of any kind, and I’d sincerely appreciate any advice you all can offer. I feel like I’m probably missing an insulation layer for the floor, so I’d really like feedback on that if you have any.

[Bbasso]

Just make sure the materials you use don't absorb moisture /water.
As for the gaps on the floor, I laid out 3/4 wood cut to fit and floating then carpet on top.
Sure its cool during the winter but nothing too worry about, besides my heater takes care of winter with ease.

[JWA]

If you simply cut 3/4" plywood to fit the floor, extending it under the flange at the bottom or the sidewalls you'll have your solid floor base and sound deadening at the same time. This plywood basically sits on top of the van floor channels---adding pressboard or anything similar isn't advised since that absorbs moisture in the form of humidity.

From personal experience the factory-style floor covering with spun fiber backing bonded to it are huge problem areas, absorbing moisture over time to the point it becomes saturated. Sadly once inside the backing it never evaporates back out. FWIW it took nearly a full 5 days of one of these mats to thoroughly dry out, laying back side up outside during a nice weather spell here in Ohio.

For a good attachment point for your eventual sidewall covering cut strips of wood to fit on top of the plywood in between that lower flange---it can be screwed in place from above the metal flange without drilling into any of the body panels that will eventually see weather; IOW no points for rust to begin.

When I've done the plywood on the floor trick I do cut a 1" wide rabbit where cut sheets will join together. By aligning your cuts in the sheets to the floor channels adding a 1/2" piece of plywood to support the rabbited joints screw them all together with counter sunk wood screws, length enough to capture the sheet "sandwich" but not penetrate the van's metal floor.

Here's an Imgur album I hastily created showing some of these steps--sorry its not captioned, sorted or reviewed very well. Apologies for that being so sloppy: https://imgur.com/a/ziw4H

That's a way to begin.

[1der]

What Bbasso and JWA said are right on.

Start with the floor for sure. If you have a passenger van with seat attach points, those fastening points can be reused IF you want the cabin floor attached to the metal floor. Just recess the TORX hold down bolts. But no screws through the plywood into the van metal floor.

First step is to POR 15 the entire van floor, front to back and 4 inches up the sides. Just in case any moisture does find its way to the metal level. Next step is to figure out where your through the metal floor penetrations are going to be located. Battery cables to inverter, water drains, Propane hoses, etc. Drill those holes and figure out a GOOD way to make them water resistant/proof. Take care with your through floor electrical connections so they do not chaff and short out. Pass thorough terminals are a great way to pas electrical current through the floors. Re-coat any drilled holes wth POR 15 to protect the metal.

For our build out, I used 1/2' Baltic Birch plywood which is plenty, but 5/8" or even 3/4" will work. Do not use the construction grade stuff, get the finished multi-ply really good quality type. That is where the Baltic Birch shines. Good holding for screws/fasteners.

If you layout the pattern, the floor pieces can be fit together with biscuit joints to keep the floor nicely level across all the pieces. The floor pieces connect to cover wall to wall just below the pinch seam towards the bottom of the wall. I did not use glue to keep the pieces of the floor together. I used Simpson Strong Tie TP37 plates with short screws as a way to hold the pieces together. This allows me to remove the flooring if interior disassembly is needed. These plates are located under cabinets and areas which are not visible. Keep in mind the areas which will be towards the walls will likely be covered with cabinets and/or seating, so locate your biscuit jointed areas under these areas. When you screw your cabinets to the plywood floor, the cabinets will also act to tie the floor pieces together.

As shared by Bbasso and JWA, forget about filling the valleys in the floor, leave them open. Do, however, consider the plywood to metal floor ribs connection though. I have used the camper shell type 1 1/2" wide foam that comes on a roll, self adhesive on one side, as a thermal and sound break. I adhere the foam to the bottom of the plywood, so the foam sits on the high points of metal floor ridges. I typically run them full length, but even if 12'' long pieces were spaced with four inch gaps, you would have plenty of support for the floor even using 1/2' Baltic plywood.

I am a fan of the Ford XLT Trim level stock carpet It is super high quality with rubber backing. I did remove the denim type material because of the moisture absorption potential mentioned. When we actually go to the vinyl flooring, the vinyl will be adhered to the individual pieces with seams, again so the floor can be removed if needed. Even when we install the vinyl, we will still use carpet runners with insulation backing / underlayment.

Hope that helps.

[rigertoflip]

You folks are great. Thank you so much for taking time to write down all these details for me. Very nice of you.

[MSD]

As always a great community with great ideas and always willing to share and help out.

[ives]

Originally Posted by rigertoflip

I am just getting ready to start building out my interior. I have really struggled to figure out how to adapt paneling to floor and walls, all the while adding insulation and noise dampening.

I'd suggest making yourself a nice cup of (whatever you like) an sitting down with your computer, opening up youtube, and typing in 'camper, van, build, flooring'.

There is definitely 'too much' information out there and not 'too little.' From the look of your question, I'd suggest spending more time on your research.

I too am building a van right now and I'm working on the same challenge you are. However, after a good many hours researching, I'm up to my eyes in options and I've learned a lot about my vehicle, the challenges, what others have done for solutions, thermodynamics, and a bunch of other things in the process.

Start with youtube. Read through this forum, look at expeditionportal.com, buildagreenrv.com, camperize.com .... there are soo sooo many.

Gotta try to do your homework before you ask others to help you with it.

[ColoRockiesFan]

Rigertoflip - I am in the same boat as you. I've had my van since September and the only thing I managed to accomplish is adding a high top. I'm overwhelmed with information and trying to decide what I want/need/can afford/etc. I've spent hours planning, researching, watching YouTube videos until paralysis set in. I finally realized that I was making myself crazy and decided to plunge in. I had my floor and bed installed yesterday by a carpenter. I love it!! And it seemed to have removed the mental block and paralysis. I am finally on my way!

FWIW - I had a van rug on the floor. I put 1/2 polyiso on top of that and then a sheet of 3/4" plywood. The wood is fastened to the van floor in a few places to make it more secure as I am securing the bed/cabinets/etc to the floor.

There are many way to do these builds. Pick a path and go for it. If it works for you that's the only thing that's important!