Chausson Floor Repair

[Jake Royd]

I have a 2008 Chausson Welcome 85.
It passed it's MOT yesterday and the garage helpfully pointed out some rot in the floor. Not an MOT issue.
The affected area lies just behind the nearside rear wheel and is probably just due to spray from the wheel penetrating the floor structure.
Inside the motorhome the area affected lies inside the bathroom, between the loo and the washbasin.
Fortunately there was a panel I could remove easily at floor level. There seems no evidence of water problems from inside.

Looking outside the area affected looks like about 9" square.
Looks like it has been there for sometime, it's not recent.

This needs fixing, of course two routes, DIY or Professionally.

The floor appears to be marine ply or similar laminate, about 1.5" thick and of course faced on the inside with the floor covering. The outside surface appears untreated.

I would appreciate any comments on whats required.

This is the plan if I do it, goes like this:-
1) Use a plunge cutting tool to cut the rot out from the underneath, part of the area extends to the straight edge of the floor
1a) Treat the xposed 'endgrain' with epoxy.
2) Use the removed section to mark out the replacement shape. In 1.5"marine ply.
3) Remove the interior floor covering and glue it onto the replacement bit.
4) Glue in place with something very strong and durable, one of the Sika adhesives.
5) Cover the area and beyond the jointline with another thin marine ply panel.
6) Seal the whole area, underneath , with epoxy.

Note, the area is not visible in the washroom.

What do you think?

The alternative is to get somebody like Cannock Resprays to do it.
(West Midlands area)
I may have to extend my area to totally remove the rot.

 

[gpat]

You sound like you know your stuff. You sound like you know a bit about joinery.

1. It's in a place that is not visible so you can get away with some error.
2. It's not structural.
3. It's not a 2021 van

I say what's to risk. I think the floors were injection protected plywood at that time as you say. The preserver would not be good enough to prevent the rot once the outer was penetrated. A good quality ply and then painted as you propose

I think you can probably do the job as well as anyone else if you are confident.

 

[pappajohn]

Think I would plunge to maybe 1" then level as much as possible.
Cut a new piece of ply and epoxy into the rebate
Once cured spread epoxy over the whole repair.
Leaving ½" of original ply will add compression strength to the repair.
Cutting out the full depth means the replacement piece is only glued on the edges.

 

[DandG5515]

Just 2 points

1, a lot of the floors are sandwiches with rigid foam, in the foam are runs for pipes and cables, just be careful wading in.

2, another option if its just on the outside, look at injecting the soft wood with resin turning to a solid. I ve used this years ago on rotten window frames and worked well.

good luck

 

[68c]

I agree with Dandg5515 answer#4, not likely your floor is solid section of 1.5" ply most likely a ply, foam, ply sandwich. Basic approach the same but as commentated rot probably only in outer ply section so hopefully no need to work inside the van. Fit mudflaps.

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[The Wino]

I agree with Dandg5515 answer#4, not likely your floor is solid section of 1.5" ply most likely a ply, foam, ply sandwich. Basic approach the same but as commentated rot probably only in outer ply section so hopefully no need to work inside the van. Fit mudflaps.

I think its a sandwich too and you might only need to do the outside layer. Is the floor inside soft in that area?

 

[MisterB]

I think its a sandwich too and you might only need to do the outside layer. Is the floor inside soft in that area?

Even if it's soft, that might be due to everything below the internal later if only, which might be unaffected by any damp.

If you do remove the full thickness, you might be able to introduce studs into the remaining sandwich (use treated timber studs machined to the exact thickness in between the layers) screw and glue top and bottom, then you can add the bottom skin, then work from the top. I would also look at adding another larger underneath section to protect where the new seams are

 

[Jake Royd]

Thanks for your guidance.
Yes, it could be a composite or sandwich construction.
Looking at the inside finished surface , it looks slightly darker and is raised slightly , which might indicate the water has penetrated to underneath the vinyl finishing covering.

Yes, as mentioned above plunging in at a shallower depth as an investigative first cut sounds sensible.

Again, i'm fortunate that it is not structural and not visible from the inside.

The vehicle already has a rudimentary mudflap fitted at build on both sides.

My first move I think will be a knife thrust to see how deep it goes and what the extent is. I can compare the load required with a good bit of floor.

The professionals will know the exact floor construction , might have a word with cannock Resprays on this.

 

[Jamesh]

If only the underside is rotten , You could remove any rot full the hole with expending foam and them overplate with 9 /12mm buffalo board - it's the stuff that truck floors are built from. Tough and weather proof.


Cheers James

 

[Jake Royd]

If only the underside is rotten , You could remove any rot full the hole with expending foam and them overplate with 9 /12mm buffalo board - it's the stuff that truck floors are built from. Tough and weather proof.


Cheers James

Yes I could, good suggestion.
I was wondering if the floor is a foam sandwich construction is the foam 'closed cell' and therefore impervious to moisture.
If so I could replace the outer layer.
I know with boats, with foam sandwich decks, once moisture gets in it's a real problem.

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[Jake Royd]

Well , I've had a quote from Cannock Resprays , it was eyewatering.
However, the way they described the process would mean it would be an absolute A1 repair , so I know they were being very honest.
Can't contemplate that sort of money , so it's off for other quotes and maybe do it myself.

 

[Swifter]

Well , I've had a quote from Cannock Resprays , it was eyewatering.
However, the way they described the process would mean it would be an absolute A1 repair , so I know they were being very honest.
Can't contemplate that sort of money , so it's off for other quotes and maybe do it myself.

I would try doing it yourself. It’s the labour costs at these places that make it so expensive .

 

[Jake Royd]

I bought the van from Hayes Leisure , so we took it back there.
A much more competitive quote and I mean by orders of magnitude.
They are Chausson dealers and knew just what to do , which is vaguely worrying as well.
It's booked in for July
I described how i would do it, involving a multitool and marine ply and epoxy.
It's pretty much what they will be doing.

Yes, I could do it myself (and have considered it) but they have the lift and the materials. I also think that if I come to sell it, the fact that the repairs were done professionally will count in it's sale price ?

 

[Jake Royd]

An update.
Hayes Leisure have now done the the work , near in mind Cannock Resprays quoted £10k and Hayes £1750.
The repair by the rear wheel went ok but they found that the 'dry rot' in the rear lower panel (behind the rear 'bumper moulding' was more extensive, upwards , than expected , so the whole thing was replaced.
Not the rear of the van but a panel parallel to it.
Inspecting it , they have done a professional job.
I can't comment on which grade of ply was used , only time will tell.

I discovered when fixing a leak under the bathroom basin that it might have rotted from the inside by the rear wheel. Short hoses and pipes and push fit fittings don't mix!
I extended them and araldited them together to avoid pulling on the shower drain continuation of the flex hose.
You don't want to pull too hard!

Expensive? Yes, but with it I have many years of motorhoming ahead.