Prep work for fitting wooden cladding

[Nabsim]

You don’t need a vapour barrier when it’s spray foamed as that is its own vapour barrier. T&G usually used in vans is pretty lightweight, you can reduce weight by only cladding surfaces you see if that’s a worry.
Definitely seal front, back, sides and ends as Nigel says. I have seen dramatic shrinkage in vans with log burners, yes it’s probably hotter in them but van will get hot inside in the summer, sealing reduces/stops the shrinkage

 

[trevskoda]

After you buy wood keep it indoors for a few weeks to dry and shrink before fitting, do leave some room for expansion when building.

 

[Eric The Viking]

Think about the weight if using T&G timber. Very easy to get near your max gross weight once you start loading.

 

[davef]

You can get western red cedar used for boat and kayak building. Its very light weight, though pricey - https://www.fyneboatkits.co.uk/supplies/wood/cedar-strips/

 

[merl]

If you varnish the whole surface back, sides and the cut ends any moisture should stay in the wood Merl so there shouldn't be any real shrinkage.

I know what you're saying kev but we all know it's impossible to stop cake or bread drying out even if you put it in a polythene bag or 'airtight ' container, I just can't believe a coat of varnish, worse still emulsion will be anywhere near airtight. Basically you're saying a strip of wood that's been so called 'sealed' for say 5 years will, when cut open, have a much higher water content inside than it's surroundings and will then start to shrink as it now starts to dry out...REALLY?
Maybe the painting before fixing method works but I guarantee it'll have nothing to do with sealing in moisture. Perhaps the paint penetrates the timber pores and stuffs up the holes and.restricts it shrinking?

 

[n brown]

well ,all i know is from experience , my van's ceiling is about 8 yrs old , water varnished . my daughters van is about the same age , oiled finish . my last van was also t and g ,painted white with bathroom emulsion ,that was about 10 yrs old. there's loads more but they're all over the place . i use reclaimed bottle insulation ,and screw the wood directly to the metal ribs with self-drilling screws .
i use 6mm ply to panel walls and build cupboards ,with 15x15mm batten as framing . i use 40 x 18mm to build fronts to hold doors i fix cupboards in place by wedging them in position then gripfilling or stixalling everywhere the cupboards touch a wall , floor or ceiling .
i also leave all wiring and plumbing till the end .
none of this methodology has caused me any problems .

 

[Pudsey Bear]

I know what you're saying kev but we all know it's impossible to stop cake or bread drying out even if you put it in a polythene bag or 'airtight ' container, I just can't believe a coat of varnish, worse still emulsion will be anywhere near airtight. Basically you're saying a strip of wood that's been so called 'sealed' for say 5 years will, when cut open, have a much higher water content inside than it's surroundings and will then start to shrink as it now starts to dry out...REALLY?
Maybe the painting before fixing method works but I guarantee it'll have nothing to do with sealing in moisture. Perhaps the paint penetrates the timber pores and stuffs up the holes and.restricts it shrinking?

Okay, I'm not having that Merl, where can I buy a van made of cake?


You need to do at least three coats of anything to seal, I've fitted cheap beech worktop in vans that are damaged, didn't bother sealing the back and undersides on the first one and it warped badly replaced it with new and did 3 good coats of boiled linseed oil and they were fine after two years, just reoiled the tops once a year as they get sun bleached and wiped down.

 

[merl]

Okay, I'm not having that Merl, where can I buy a van made of cake?


You need to do at least three coats of anything to seal, I've fitted cheap beech worktop in vans that are damaged, didn't bother sealing the back and undersides on the first one and it warped badly replaced it with new and did 3 good coats of boiled linseed oil and they were fine after two years, just reoiled the tops once a year as they get sun bleached and wiped down.

Here's one made of wafer biscuits if that'll do?https://images.app.goo.gl/MeRsqjmDbWejqord7

 

[Robmac]

I ripped down some 4x2 pine for a project once (Not a campervan). Put it through my table saw set at about 4mm.

I then glued it to battens at 400mm centres, stained it and then applied varnish. OK, not strictly tongue and groove, but a lot lighter and a similar effect.

 

[merl]

I ripped down some 4x2 pine for a project once (Not a campervan). Put it through my table saw set at about 4mm.

I then glued it to battens at 400mm centres, stained it and then applied varnish. OK, not strictly tongue and groove, but a lot lighter and a similar effect.

I considered doing the same with 3mm ply cut into 100mm ish strips and then overlapped slightly before fixing. Waney edge for that rustic look maybe?

 

[n brown]

clinker built . or just cut 'v' groves in the face of 6mm with a router

 

[Thistle]

I wonder if the op has read any of the replies yet! Especially the one from @Pudsey Bear who gave the obvious answer assuming that is what the op used…..

Perhaps we will never know.