Starting on my Sprinter

ctaniab

Full Member
Hello, have just joined the forum in the hope of avoiding too much wheel-reinvention during my Sprinter conversion. Am a complete newby and know jack-shit at the mo, so I have a long, steep learning-curve ahead of me. But I'm enjoying the ride so far... I've treated all the rust (I hope - yes, yes, it's a Sprinter :rolleyes:), have removed the bulk-head and fitted swivels for the seats, fitted 2 x skylights, 2 x side windows and 3 x solar panels, fitted an external water-tank and just insulated and re-laid the floor. Am currently trying to get my head round wall and ceiling insulation but struggling to decide which way to go. What a bleeding' minefield! Has anyone got experience of PolyNor spray-foam? https://www.polynor.ru/uploads/POLYNOR eng.pdf Almost all the youtube vids are in Polish or Russian, so little help. Any experience of this from anyone would be really welcomed :)
 

Edina

Administrator
Welcome to the forum.
Some folk swear by foam but one word of warning - any body repairs to areas foamed will be very difficult.
 

ctaniab

Full Member
Thanks for the welcome, Chris. And yes, I saw that worry about foam flagged up in other posts. But I'm wondering... why's it any more difficult than, say, finding and treating rust under celotex boards (especially if they're glued with sikoflex or spray-adhesive)? You still have to strip everything back and clean it all off. Is foam that much harder? If anyone has personal experience of both, for comparison, that would be so helpful. The benefits of the spray, as far as I can see, apart from its very low thermal conductivity and water resistance, it that it's so quick & easy to use - much easier to fill all those cavities.
 

Millie Master

Full Member
Hello and welcome to our forum.

So very pleased to read that you have treated all the tin worm on your Sprinter, have you also now fully treated the entire underside, door internal and sills with a decent preventative ?

As for the spray foam, you possibly know already that my van is spray foam lined, I had mine done by a professional outfit and am well pleased with the thermal performance. As for the comment made by Chris, yes I can understand people having such concerns, but in my case as I have safely driven well in excess of 1,500,000 miles since my last small accident, then I hope body repairs won't be something for me to worry about.

With regards to the Polynor product you have listed, no I have never heard of it before, however having looked at their website I have the following observations to make.

Cost; I haven't got the foggiest idea how much it would cost but as and when you are spray foaming a van there is always bound to be quite a lot of wastage unless you are an absolute expert, by this I mean the very lumpy finish that is very evident throughout the Polynor website which, when converting a van, you have to cut back to get as smooth a finish as possible.

Heat; when you are using these products, the chemical reaction that results can cause distortion of a vans body unless you are exceptionally careful. To do it properly you have to apply the thinnest of layers and keep going over it over and over again.

Closed Cell; I notice that the Polynor product isn't entirely closed cell and has some open cell content. You might want to ask them what level of fire resistance their product has as open cell foam burns like nothing else!

If you need the name of an amazingly brilliant company who could do this for you, let me know, they are based in Sheffield.

Phil
 

ctaniab

Full Member
Thank you for the welcome and for your helpful thoughts and advice about foam insulation, Phil. I did look into getting the van professionally insulated (maybe from the same outfit you mention), but they have a minimum fee of £1200, so that idea was dead in the water. Polynor is 70% closed cell; not sure what the spec of commercial foams is (do you know?). I'm waiting to hear back from the head office in Russia and/or the uk distributor with info about flammability. Like all camper vans, there will be a lot of wood in my vehicle anyway, but obviously I don't want something with a really low flash-point where my cables run. Re. distorting the van's shape, yes I did read about that, especially if it's applied very thick; so thanks for the tip about very gradual application. One more question, Phil: did the company who did your van spray inside all the ribs too, or just on the panel faces (hope that makes sense)? By the way, your van is dead smart
 

Millie Master

Full Member
Thank you for the welcome and for your helpful thoughts and advice about foam insulation, Phil.
Bloody hell £1,200, geeeeeeeeeees, if you are talking about MPI there prices have gone up enormously. If you contact Jake Clarkson @ One Insulation https://www.oneinsulation.co.uk/, mention my name Phil McDonald and I hope he will recall giving me a special price of (I hope this senile old brain of mine recalls correctly) only £12 per sq. mtr.
I can assure you that the quality of their work is quite literally head and shoulders better than the job done on my van by MPI, One Insulation is as smooth as a babies bum whereas MPI's looked as lumpy as lumpy could be and it resulted in me having to spend an enormous amount of time cutting it back.
The foam that One Insulation use comes from America and it is 100% closed cell as it has to conform to all the building regulations stipulated by the government. Their main work is spray foam lining roofs of old houses, lining boats, lining storage containers etc.
The difference between Ones and where I had mine done is that they are constantly checking the temperature of the mixture, and by constantly, I mean about every 15 seconds!

As for the ribs yes, to do the job properly they have to be filled with the foam, otherwise you will get damp inducing cold spots.

As for the flash point of closed cell foam, it simply doesn't burn.

With regards to your cable runs, in my build, I actually didn't have the floor spray foamed, instead I lay the 25 x 50 roofing laths that I used as batons on the floor and then fitted very tightly fitting Celotex (or similar) between the ribs. The reason why I did this is that I had 1 x long valley along the entire length of the floor and 2 x cross valleys into which I ran all my cables, water pipes and gas pipes. Then, wherever I have a plug socket or light I ran the cables vertically feeding them through trunking that I then recessed into the already sprayed walls. For the floor I then laid a 12mm marine ply that I had already varnished both sides.

One Insulation are as I said previously based in Sheffield and if doing vans, they normally will only do them at weekends, unless that is, you can get several people together at any one time to do their vans as well.

One final and very important point, you have to mask off all the areas that you don't want spraying, this is a balls aching job to do I can assure you, but it has to be done and it is also best practice to have some kind of curtain fully sealed to stop any overspray going into the cab area.

Another point worth considering is how to insulate the doors, my sliding door has a mixture of both spray foam and rock wool, but I didn't do the cab doors or indeed the back doors. With hindsight I would have insulated the cab doors but not the rear doors, the reason being that in my build, there wasn't any need to insulate the doors as the shower/loo room is fully insulated (using Cellotex).

If I can help in any other way, don't hesitate to do so.

Phil

ps. don't forget to insulate the area above the cab.
 

ctaniab

Full Member
Thanks once again for such helpful suggestions, Phil, and for the name-drop. I've contacted One Insulation and am waiting for a call back - it'll be interesting to see what they can offer. (And if anyone reading this contemporaneously (mid Oct 2019) is interested in approaching this company for a multi-vehicle price, just let me know.)

Thanks for the tip about foam-filling the doors and above the cab. Do they simply spray into the void above the cab lining (ie leave the lining in place) or do I have to remove it? If the latter, how on earth would I protect the cab??

Re. floor insulation and cabling; we decided against battens and celotex/similar as we're both really tall and need all the headroom we can get. So I've laid Alreflex 2L2 (huge roll kindly donated by a builder friend) under the floor panels and our cables will instead be running up and over - yes, a little further, so some inevitable voltage-drop, but we figured that's better than stooping forever more in what will be our full-time home for the next few years (we've sold up and are heading out to see as much of the world as we can manage overland).
 

Millie Master

Full Member
Thanks for the tip about foam-filling the doors and above the cab. Do they simply spray into the void above the cab lining (ie leave the lining in place) or do I have to remove it? If the latter, how on earth would I protect the cab??
I honestly can't reply exactly about spraying the area above the cab in a Sprinter as I have never seen one, but in the H2 version of the Renault Master, the above cab has a load tray for the storage of small items above which is the bare painted metal of the roof.
I simply covered over the load tray with polythene and the roof was then sprayed, all be it poorly, but it does make an enormous difference.

As for the floor, unless you are exceptionally tall, I would have thought that a standard roof of a Sprinter will allow even a very tall person to stand. When it comes to insulation, I honestly can't stress how important it is to have the highest possible levels of insulation for both cold winter days and exceptionally hot summer ones as well and the floor is one of themost important areas toinsulate as if yourfeet are cold, then normally speaking, so will be the rest of your body.

Philip
 

ctaniab

Full Member
Even with a high-top, we only just have head clearance (by about 1mm for my other half), so there's genuinely no room for raising the floor any further, sadly - and that's before the lino goes down. Just about gives us room for a rug, if needed. I'm learning fast that, as with everything, compromises always have to be made (unless money's no obstacle). Hopefully, most of our worries will be about keeping the heat out rather than in, as we plan to be in warmer climes whenever we can.
 
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