Caravan roof lining too heavy

[KeithB]

My pop top build has a curved roof and a curved ceiling inside.  Here's the half built roof upside down.



I just took delivery of three sheets of 3.6mm Gunnersons RV coated ply which is commonly used in caravans and motorhomes. I assumed that it would be reasonably light. But at 3.3kg per sq m, it's going to add about 20Kg to the weight of the roof.

So I am casting around for alternatives. The ceiling lining is supported every 550mm and the curve will give it some rigidity. 1mm aluminium sheet is still over 3Kg per q m. I am wondering about just using Laminex or Formica which is about 1.5 Kg per sq m.

I'd appreciate any suggestions.

Keith

[edz]

Thinking well out side the square,   You could attach some 75 / 95%  Shade cloth or front runner carpet [ Auto upholstery ] or other type vinyl / cloth material .. light weight easy to remove / replace etc, textured finish though .
Mark G did a soft roof lining with foam insulation between it and the roof in his Skid Mk3 camper

[KeithB]

Edz, how would I get it to conform to the internal curve of the roof?
Keith

[edz]

My take on it, it could be done a bit like a car roof head lining, Or attach one end pull it up tight [ could even be done via velcro tape  to hold ]  then pull up the next section to tension it,  velcro to hold in place, pull up the next section to tension etc etc

[KeithB]

A cardboard style lining maybe?
Keith

[edz]

PVC Coreflute  Sign board or Suntuff Poly Carbonate if you wanted too, nice and light easy to curve / strong  ?

[KeithB]

Edz I was just logging to post a question about Corflute and there you are with the answer.
I can get it in black from the green shed.
Thanks mate.
Keith

[edz]

Just on the PVC Coreflute its pretty soft and will mark easy if you wanted to go Ala natural ..
For what its worth maybe see if you could find the Poly carbonate Suntuff in 8mm and go with a smoked ceiling or the clear and paint the side thats towards the roof  or cover it with a cloth / carpet etc .
Im looking at using one or two of these as an end wall covering in my Cross over When n if I get motivated enough to start it
https://www.dresslily.com/wall-tapestries-c-310.html

[Pottsy]

Polystyrene coated with lightweight canvas and bondcrete to stiffen and firm up, can then be painted to your choice of colour, will be left with a slight textured finish. ( May need two or three coats of Bondcrete) Try with some scrap to see if it will do the job for you.

Did this once with a cheap polystyrene eski and it lasted about 10 years. Roof lining shouldn't suffer the knocks the eski did.

[KeithB]

Thanks Pottsy
Keith

[Hoyks]

You want a hard finsih?

Line it with polystyrene and cover it with a stretch fabric like track suit material. Once its all upholstered, paint the fabric with epoxy and then paint it with a high solids paint.

[Pottsy]

Might be of interest Keith

http://www.tnttt.com/viewtopic.php?t=39759&p=727949

[KingBilly]

Just be mindfull of the finished weight Keith if using multiple mediums to create the finished product.  Glue and paint are heavy.  Ever picked up a 10 litre drum of paint.

KB

[KeithB]

Thanks everyone. You have certainly given me something to think about. Right now I am leaning towards corflute or foam board which I can cover with vinyl wall paper to get a nice finish. If anyone needs three sheets of Gunnersons coated ply, please let me know.
Keith

[Alan Loy]

Polystyrene coated with lightweight canvas and bondcrete to stiffen and firm up, can then be painted to your choice of colour, will be left with a slight textured finish. ( May need two or three coats of Bondcrete) Try with some scrap to see if it will do the job for you.

Did this once with a cheap polystyrene eski and it lasted about 10 years. Roof lining shouldn't suffer the knocks the eski did.

You can use EPS, calico and PVA if you want it lighter.  There are heaps of stuff on this technique google poor man's fibreglass or ghetto fibreglass.  I have used titebond 2 but it's hard to find atm so recently used Sellys aquadhere external with similar results.

[Fizzie]

Im looking at using one or two of these as an end wall covering in my Cross over When n if I get motivated enough to start it
https://www.dresslily.com/wall-tapestries-c-310.html

& then change from beach to forest depending on where you go camping

[DannyG]

Im not sure if it has been mentioned but if you are going to be putting polystyrene insulation in between your space you can get a very thin fibreglass product that would be lighter than ply.

A place down here call Penguin Composites make it to size and roll it up for delivery. It is only about 3mm thick and lighter than you may think but it needs support. They say it will bridge across 500mm gaps but I have seen 'cupping' on motorhomes etc that has used the product so it needs something like the insulation to fill the spaces.

[duggie]

Im looking at using one or two of these as an end wall
https://www.dresslily.com/wall-tapestries-c-310.html

You would not want to wake up under this ,

Sorry the image did not load , it was the stone wall one .

[prodigyrf]

Did you investigate all the options beforehand?
https://styromax.com.au/why-styromax/#diy
Obviously a judgment call paying a bit more with professional gear like that with DIY but then there's the resale to consider later on. I've no idea what they charge for panels like that but you wouldn't want to find out later it was line ball materials wise with framing, insulating and double cladding.

[KeithB]

Did you investigate all the options beforehand?
https://styromax.com.au/why-styromax/#diy
Obviously a judgment call paying a bit more with professional gear like that with DIY but then there's the resale to consider later on. I've no idea what they charge for panels like that but you wouldn't want to find out later it was line ball materials wise with framing, insulating and double cladding.

I had a good look at Styromax beforehand but went with Polycore because of its light weight and superior joint strength. I have already formed a curved roof line but have put in  extra framing to cope with a man's weight on the roof. The ceiling lining is to accommodate a great mess of wiring for 9 solar panels plus lights and so on.

Keith