Preparation steps before fitting cladding to walls

[poindexter]

Hey Forum, I am at a critical stage of my campervan conversion project and looking for some advice here please.

I have insulated with spray foam and now would like to proceed with cladding the walls with tongue and groove wooden cladding. I have installed the wooden framework to attach the cladding to but am a little concerned about moisture.

It would be very difficult to create a moisture barrier with the tongue and groove. It is definitely what I want however.

Just looking for general advice really on what I should do in preparation for fitting the cladding? I did think that I could put in a 3mm ply underlay and seal it around the edges but that would be a fair bit of extra work, cost and weight on a Transit Jumbo.

The van is well ventilated with two floor vents, a spinning vent on top, two skylights and two roof vents.

Should my ventilation be good enough that I don't need to worry so much about airborne moisture or should I do some extra prep work? If so are there any good suggestions that are faster, cheaper and lighter than what I had in mind?

Appreciate your responses...

 

[Mikeco]

I would put a layer of aluminium faced bubble wrap on with taped joints and then 6mm ply. I would not be using t & g board though as it will shrink and look a mess.
I used a 3mm maple board on top of the 6 mm ply, this takes away some of the self built look that you get using t & g boards.

 

[Gromett]

Usually with two part polyurethane foam you shouldn't need a vapour barrier as that is provided by the foam. But your foam looks odd (sorry).

There are many methods for a vapour barrier but literally any plastic sheeting will do the job. My preferred material is damp proof membrane plastic sheet from a builders yard. Tough stuff.

Like Mikeco I would avoid T and g as it will cups, bow, warp, shrink and expand over the seasons. If you definitely want T & G, i would highly recommend treating every surface before fitting. If you simply install it then coat the front. The back will absorb moisture but the front won't and you will and up with cupping. I recommend cutting to size then treating/sealing both faces, edges and ends, two treatments on ends as they can absorb a lot.

 

[Tombola]

In depth with Greg virgoe

 

[Wissel]

If it helps, you can have plywood CNC'd to look like T&G. Then you get the look without the warping issues that will happen.

I'm a van builder in Horncastle (just up the road from you) and have a CNC place next door. They do loads of bits for campers and are good value.

Here's one I built using CNC'd ply:

Actually I'm doing another at the moment.

^{_{Subscribers  do not see these advertisements}}

 

[poindexter]

thanks for the advice... Can you recommend some good options for what kind of wood to use for the walls? I do like the horizontal wooden board look....

 

[Wissel]

just a normal wicked ply will CNC fine.

The best stuff though is Garnica poplar lightweight ply. I have sheets here if you wanted to have a look.

 

[poindexter]

I really like what you have done there with that rear cupboard. Nice job. What wood did you use for this? Are those router lines that you have into it? Such a nice look.

 

[poindexter]

just a normal wicked ply will CNC fine.

The best stuff though is Garnica poplar lightweight ply. I have sheets here if you wanted to have a look.

I would be interested to take a look please

 

[Wissel]

Pm sent

^{_{Subscribers  do not see these advertisements}}

 

[mitzimad]

magnums use 3mm cheap ply glued to the ribs and overlay it with 3mm wall boards