# Advice on small area of damage on underside of van



## gorsecover (Jun 29, 2011)

Hi Folks,
Have had a small amount of damage to underside of floor on my van since buying 3 years ago.
This is very slowly getting worse and time I did something about it.
It looks as though a stone has damaged the plywood on the underside and one of the ply layers is starting to break away. Dont think it is de-lamination from above as there appears to be no soggy areas although this is beneath the fridge it is a bout 2" by 1/2" and a smaller area close by.
Was thinking of getting some exterior ply,covering it in pva adhesive and glueing it to the underside.What do you guys think????
Mant Thanks
Martin
ps cant get pics at present as motorhome in storage.


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## teddyj (Jan 3, 2012)

Hi
I would not use P.V.A. Try one of the sicaflex products they are water proof,flexible and strong.

Hope this helps.

Ted


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## gorsecover (Jun 29, 2011)

*Help please*

Has no one else any advice please
Martin


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## rayrecrok (Nov 21, 2008)

Hey up.

If it is only cosmetic damage as you seem to be pointing out a patch covering the area would be fine.. 

Just make sure the medium you intend to use for the patch is suitable, if you are using exterior grade ply then give it a coat of preservative that can be painted over making sure the end grain on the edges are well soaked, when dry paint it and when dry stick it on with Sicaflex adhesive mastic, available at most camping marine and motorhome outlets, or google is your friend.

Gob it up all over the patch then apply it to the area in question, it should grab in place so no mechanical fixings should be used as they are a source of future damp if they rust allowing water penertration.

You can get some timber just to prop the patch and squash it on to the existing floor to make sure any air voids under the patch are removed. A clean up of any mastic that sqeezes out can easily be done when it has gone into the easy cut rubbery stage just before it sets, a final coat of paint over the area will sort it.

ray.


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## rosalan (Aug 24, 2009)

Please do not leave any area of damaged wood, for as you observe, it will never get better on its own but has the potential to become serious.
The alternatives you have and I am sure you can already guess these, is to cover the damage or fill the damaged area but without seeing the extent and nature of the damage, it would be hard to determine which of these to recommend.
Either treatment will require a permanent seal to the damaged ply, which given time WILL become porous.
Boatyard type repairs and materials are geared towards protecting wood from water. If you are able to visit a chandlery they should be able to recommend the most suitable sealants and covering materials. I have been down this road and visited a chandlery in Malden, Essex who gave me excellent advice on repairing some wet timbers in an earlier van. It involved two part mixtures of materials that soaked into the wood and sealed and protected it. From memory I think it even coped with wet or damp wood. It worked better than I had hoped for. My timbers were internal and yours external, so an additional flexible coat of any semi pliable material that could act as an underseal skin over the whole potential area of damage should complete a repair. The difficulty may be in making sure that no water is trapped inside.
I am NOT an expert but have had some success along these lines.

Alan


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## SNandJA (Aug 22, 2008)

I think the use of exterior/marine ply is the key and very important to ensure it is dry before using any type of mastic like Sikaflex.
Stixall alternative small tube

I had a similar issue and found the product Stixall which will cure under water see below
Skip towards the end to see it used to seal a gutter full of water

I've used this and Sikaflex and think the Everbuild Stixall is much better and cheaper and comes in handy small tubes of white black grey and clear that you could keep in the van.....

Steve

Edit I think Ronseal do a wood hardening product which can be applied to wet wood but this is intended for window cills and wooden frames that have got wet behind the paint/putty and started to soften. Worth reading the label but always identify and source of damp before treating and sealing. My issue involved a badly fitted shower outlet leaking into the floor.


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## gorsecover (Jun 29, 2011)

*Thank you all*

Thank you all so much for your help it really is very much appreciated.
Martin


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## inkey-2008 (May 24, 2008)

If it is under the fridge make sure the water evaporation tank for the fridge is not leaking. Mine had a small crack so I fitted a longer drain pipe and it now drips out side the van.

Andy


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## SNandJA (Aug 22, 2008)

The fridge leak seems a good one to check before sealing the damage. If your van is anything like mine there is rarely any evidence of mud or water on the underside. Mine is 10 years old and there was no dirt on the underside of the floor. When I did my repair to a laminate floor, I trimmed out the wood using a Stanley knife to reveal an expanded polystyrene layer. Then inserted a new piece of ply secured with Stixall (which didn't have any effect on the polystyrene). Then finished off with a patch of underbody seal. The ply laminate has a thin black plastic layer as the final finish.
If you want to check the source you could always do a temporary fix with the same cut out the damaged area solution with Stanley Knife and use some Duct Tape to make a temporary repair so you could remove it after a while to check for any post repair leak from above?
Leaving out the mastic/adhesive for any repair allows any trapped moisture to escape. Problem with Stixall or Sikaflex is that they prevent the ingress of water so obviously they'll prevent it getting out if you have got a leak above.
If like my van there is little evidence of dirt being picked up from the road then you can probably afford to leave the area exposed to investigate the source?

Steve


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