14 months after buying the van I'm finally about to start converting it!

[Taipan]

I bought a 2003 LWB Realy back in No 2011 and due to a variety circumstances I had to pretty much park it up and leave it at my Dads place. Finally got it home the other weekend and am going through it to get it ready for the MOT. Been removing snapped caliper sliding bolts and all other joyful things that stick and rust after being parked up for ages. Sigh. Still feels good finally making a start on it.

Its not ever going to the best or most desirable conversion in the world as I'm using a mid 80s Lunar caravan interior for most of it, but it'll do for now. Thsi will be the one i cut my teeth on so to speak. I'll start hunting/scrounging and even buying materials after payday! So if anyone knows the best sized wood for batoning and ply thickness for floors/walls/roof I'd be glad to hear about it. Or any other obvious things to look out for when looking in builders skips/ebay etc!

Will add disaster sequence, sorry build progress pictures as they happen which will hopefully be this year but after the glacial speed so far I can't guarantee it!

 

[Poppy]

I asked the same question a little while ago.....so I've copied & pasted one of the reply.
Or if you stay on this forum & look up the heading 'what mm' & you'll find more




3mm Hardboard on the ceiling

6mm on the floor but it is supported by battens and rigid insulation all on top of 9mm original ply floor

6mm on the walls

6mm for the cupboards and furniture generally

9mm for the cupboard ends/supports/curved profiles.

18mm MDF for the shower compartment and bed partition walls

 

[rockape]

I bought a 2003 LWB Realy back in No 2011 and due to a variety circumstances I had to pretty much park it up and leave it at my Dads place. Finally got it home the other weekend and am going through it to get it ready for the MOT. Been removing snapped caliper sliding bolts and all other joyful things that stick and rust after being parked up for ages. Sigh. Still feels good finally making a start on it.

Its not ever going to the best or most desirable conversion in the world as I'm using a mid 80s Lunar caravan interior for most of it, but it'll do for now. Thsi will be the one i cut my teeth on so to speak. I'll start hunting/scrounging and even buying materials after payday! So if anyone knows the best sized wood for batoning and ply thickness for floors/walls/roof I'd be glad to hear about it. Or any other obvious things to look out for when looking in builders skips/ebay etc!

Will add disaster sequence, sorry build progress pictures as they happen which will hopefully be this year but after the glacial speed so far I can't guarantee it!

Good luck with your project

 

[Aladdinsane]

I asked the same question a little while ago.....so I've copied & pasted one of the reply.
Or if you stay on this forum & look up the heading 'what mm' & you'll find more




3mm Hardboard on the ceiling

6mm on the floor but it is supported by battens and rigid insulation all on top of 9mm original ply floor

6mm on the walls

6mm for the cupboards and furniture generally

9mm for the cupboard ends/supports/curved profiles.

18mm MDF for the shower compartment and bed partition walls

Not sure 'bout these recommendations, Hardboard and MDF are both susceptible to moisture and MDF is HEAVY. I wouldn't recommend 6mm ply on the floor unless the supporting batons were VERY close together. Rigid insulation (Kingspan etc.) soon becomes deformed with pressure, Push it with your finger and see, then imagine constant use underfoot?

 

[Poppy]

Not sure 'bout these recommendations, Hardboard and MDF are both susceptible to moisture and MDF is HEAVY. I wouldn't recommend 6mm ply on the floor unless the supporting batons were VERY close together. Rigid insulation (Kingspan etc.) soon becomes deformed with pressure, Push it with your finger and see, then imagine constant use underfoot?

This is just one of the posts I got when I asked the question. I'm putting 9mm on floor, along with batons set at 30 as well as a few cross sections, with rigid insulation

 

[hextal]

Id suggest 9mm on the floor and 6mm everywhere else. And go for wbp plywood (water and boil proof).

3mm on the ceiling will likely bow between fixing points.

I used 9mm on the floor with batons at400mm centres and its still deflects more than id like so probably try 9mm with batons at 300 centres on the floor.

Always good to learn from other peoples mistakes rather than your own.

Edit. Missed that last post, oops.

 

[Aladdinsane]

Quote
3mm on the ceiling will likely bow between fixing points.

If you use the van roof ribs as fixing points, you will not have any bow/droop/warp with 3mm ply.

 

[hextal]

I know a few people to have some bowing issues with 3mm but i guess if you have very closely spaced ribs it may be ok. you could always screw longitudinal batons to the board to stiffen it and run the grain longitudinally i suppose. the deeper the roof curvature the less the board will sag too.

 

[Taipan]

All great and helpful replies, thanks everyone.

I had a quick look in the back of the van last night and a lot of it is already plyed out! Didnt even remember that! Its a bit grubby but intact and none of the grubbiness will show as it'll be covered anyway. Not sure if its thick enough but if the walls are too thin they'll probably do for the roof. I'll have a better look tomorrow.

 

[chubadub]

just like mine ,finished :hammer:

 

[Taipan]

just like mine ,finished :hammer:

Lol, I was thinking minimalist but the wife wasn't so keen!

For the floor and side batons what sized wood is commonly used?

 

[hextal]

Lol, I was thinking minimalist but the wife wasn't so keen!

For the floor and side batons what sized wood is commonly used?

Depends on how thick your insulation is as they will be laid between the panels.

 

[Taipan]

Depends on how thick your insulation is as they will be laid between the panels.

Ah, got ya. Just trying to work out which insulation to use for cheapness. Looks like it'll be loft/wool type with that foil bubble wrap stuff taped over it?

 

[MORGANTHEMOON]

Good luck with everything.

 

[hextal]

Ah, got ya. Just trying to work out which insulation to use for cheapness. Looks like it'll be loft/wool type with that foil bubble wrap stuff taped over it?

insulation is a whole big (highly subjective) issue in itself. I went for kingspan as it seems to be the more standard thing and won't settle. If you are going for normal loft lagging it may be worth adding a vapour barrier. The other issue to bear in mind is that the loft lagging in the walls will likely drop over time, as it gets vibrated by driving etc so after a while it may need re-packing.

If you are fixing the ply to the van ribs its probably worth adding a baton first, just so that you don't end up with a cold-bridge (where the inner surface is only insulated locally by the 3-6mm of ply). I'd probably suggest stainless self tappers for the inner fixing, so they dont corrode over time due to the moisture from cooking/breathing and start leaving little rust spots on the wall/ceiling coverings. You can fix batons to the van with sikaflex, or self drilling screws (they're fantastic), or both.

I glued the batons then screwed them to the van (while the adhesive set), then thought "i may as well leave the screws in", then thought "why did I bother with the glue in the first place".

 

[Firefox]

Not sure 'bout these recommendations, Hardboard and MDF are both susceptible to moisture and MDF is HEAVY. I wouldn't recommend 6mm ply on the floor unless the supporting batons were VERY close together. Rigid insulation (Kingspan etc.) soon becomes deformed with pressure, Push it with your finger and see, then imagine constant use underfoot?

They were my recommendations. I have had the van for 3 1/2 years now and everything works perfectly. Combination of ply and kingspan/celotex works quite well even underfoot.

MDF is heavy but I used it sparingly. Only the main walls which have big doors in them. And yes it is moisture susceptible but shower compartment is fully lined with vinyl. Other places subject to condensation etc have not affected the MDF.

Some people say don't use MDF on account of the weight but I suspect these people are often armchair builders who just rely on hearsay. I'm actually a chartered structural engineer and calculated all the weights beforehand. After the conversion I took the vehicle on a weighbridge with two people and full payload of provisions, possessions and water etc on board. It came to 2800kg. Maximum weight is 3300 kg, so I have 500 kg to spare even using MDF for some walls

 

[hextal]

So. A fellow chartered engineer with a self build movano...

Good stuff.

Hope you were more successful than me at reigning in the over-thinking of anything vaguely structural.

 

[Firefox]

You're right, I didn't do any calculations on the floor or indeed any other deflections :lol-053:

But the way it works I guess, is that Kingspan type can take low pressures, and the 6mm ply spreads out the loads enough so although you can deform it by sticking a finger in it, it's not subject to that kind of local pressure from feet, while the Kingspan can prevent deflection of the ply between 400-500mm spaced battens by giving it a kind of floating uniform support. It's an interesting lightweight sandwich where neither component on their own would work, but together they make a team.

18mm Mdf spans very well 600-800mm without additional stiffening which does save on weight in that respect. No doubt vohringer ply would have been lighter but that stuff is so expensive and you can't just pop down to Wickes and buy a sheet when you need it in the evening which is the way I work. I tend to use off the shelf components where possible.

The ribs of the van are about 600 c/c bit by the time I had battened in between, the hardboard only has to span about 500mm under no load other than own weight and rockwool so it really doesn't sag appreciably. I also faced it up with camping mats and leatherette stretched over and staple gunned on the back so the hardboard was better than ply for accepting staples without too much fuss. Also cheaper than ply. There is method in my madness! Waterproofing was a slight concern, but I have had some panels down, and the hardboard/rockwool has not been affected by interstitial condensation. They are as good as they say they went up and I am in the van 365 days a year so those 3 1/2 years are equal to 12 years of any typical camper van usage. I'm not saying it would be suitable for a bathroom and daily hot steamy showers but my bathroom is lined with waterproof vinyl and sealed with mastic so that is pretty waterproof.

 

[hextal]

I actually agree on the kingspan, it's fairly tough stuff, I was planning to use it as partial support to the flooring. After walking around on offcuts is certainly durable. I went for 45mm though which meant that with the std size timbers and sikaflex beading there ended up being about 5mm between the ply and the kingspan, so it deflects more than I hoped.

I've seen some designs where the ply has been laid directly onto the insulation board with no batons, and they appear to have worked fine. My concern with those would be more to do with adhesion of the two materials rather than the board getting damaged

 

[Firefox]

I lightly screwed down the 6mm ply to the battens. I think they were 25x38 sawn treated and the celotext was 25mm.

Also the original ply lining floor of the van was in left place. Thus I had a nice smooth floor to lay the celotext on. I didn't lay it on metal ribbed van floor which would have seen it deform.