Soft Floor Syndrome

Tootles

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Deceased RIP
Sep 14, 2013
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Was a newbie, now a Middie.
And so, what causes a 'soft floor feel' in a dry van?? Is it the ply de-laminating??? Could understand if the area concerned had been wet, but no sign. Is it just age? It's not a 'problem' on ours, but you can just 'feel' it a bit when walking on the 'infected' area.
Lastly, a problem to worry about...Or not??
 

tambo

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Jun 21, 2014
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What's the underside of the floor like?

Often it gets damp from underneath which eventually causes it to soften
 
Aug 6, 2013
7,866
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Kendal, Cumbria
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since 1999
The floor to foam glue lets go. It may be affected to an extent by natural dampness but the real cause is that manufacturers have been forced to use eco-friendly adhesive which isn't as good as that used a few years ago. I believe they've resolved the problem with later vans.

My advice, borne of experience with a couple of caravans, is don't leave it. Because the floor is less rigid where it occurs flexing of the plywood indents the foam, then the plywood stretches, then it indents the foam even more. Eventually the plywood forms humps and dips that are difficult if not impossible to get rid of. There's a simple and permanent fix (DiY if you're up to it) that involves drilling small holes around & across the affected area then injecting pourable epoxy resin with a syringe. It's a job that will take an hour, a days wait, then however long it takes to re-lay the carpet / plastic flooring.
 

Snowbird

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Apr 24, 2009
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The floor to foam glue lets go. It may be affected to an extent by natural dampness but the real cause is that manufacturers have been forced to use eco-friendly adhesive which isn't as good as that used a few years ago. I believe they've resolved the problem with later vans.

My advice, borne of experience with a couple of caravans, is don't leave it. Because the floor is less rigid where it occurs flexing of the plywood indents the foam, then the plywood stretches, then it indents the foam even more. Eventually the plywood forms humps and dips that are difficult if not impossible to get rid of. There's a simple and permanent fix (DiY if you're up to it) that involves drilling small holes around & across the affected area then injecting pourable epoxy resin with a syringe. It's a job that will take an hour, a days wait, then however long it takes to re-lay the carpet / plastic flooring.
Thats the only permanent way to cure it.
 

Abacist

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Oct 15, 2013
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I did this on my old caravan which was always dry as a bone and it worked a treat. You can either do it from below or from above and I did mine from above and was glad that I did. I supported the floor from below whilst I did the work.

Having drilled a matrix of holes in the floor you mix the resin with fixer and then inject with supplied syringe into the holes until the liquid starts to seep from the adjoining holes then move onto the next hole. You then plug the hole with a piece of supplied dowel. When all done leave until set the next day and you then have to use a belt sander or similar to remove the set resin and protruding dowels. The floor is then as good as new and solid as a rock.

Just remember that the floor is a sandwich of ply, insulation and then more ply. You must only drill through the one layer of ply and some of the insulation - don't go through both layers of ply or your resin will all run out onto the floor and set making an unholy mess!
 

hilldweller

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Dec 5, 2008
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drilling small holes around & across the affected area then injecting pourable epoxy resin with a syringe..
I'm puzzled. The normal resin ( as from Halfords ) dissolves the foam in a Burstner.

"Choose you next resin carefully Mr Bond".
 

camocam1

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Aug 28, 2012
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Watch how you drill as was in local caravan repairers a month or so back and the young fitter was fixing á soft floor except he drilled right through and the epoxy ran out under Neath boss not best pleased !!!
 
OP
Tootles

Tootles

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Deceased RIP
Sep 14, 2013
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Was a newbie, now a Middie.
Right. I haven't got any foam. The floor is dry above and beneath, with no sign of flexing. As far as I can tell, the floor consists of 3/4 ply, with just the standard lino on top. This is a 1992 Hymer coachbuilt. The soft bits are nowhere near to the hab door, but in two places in the centre corridor, one by the dinette, and one outside the loo door.
 

tambo

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Jun 21, 2014
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Right. I haven't got any foam. The floor is dry above and beneath, with no sign of flexing. As far as I can tell, the floor consists of 3/4 ply, with just the standard lino on top. This is a 1992 Hymer coachbuilt. The soft bits are nowhere near to the hab door, but in two places in the centre corridor, one by the dinette, and one outside the loo door.
Then there can be only one solution!


Lay off the pies there's nowt wrong with floor......your just too heavy :p
 

Hymie

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Nov 29, 2013
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Right. I haven't got any foam. The floor is dry above and beneath, with no sign of flexing. As far as I can tell, the floor consists of 3/4 ply, with just the standard lino on top. This is a 1992 Hymer coachbuilt. The soft bits are nowhere near to the hab door, but in two places in the centre corridor, one by the dinette, and one outside the loo door.
We have 91 Hymer 564, I was worried the floor was delaminating due to the squeaking whenever you hit the same spot.

Did the bouncing on the spot bit and lifted the carpet but couldn't feel anything wrong.

I stripped out the heater, rebuilt and refitted it and hey presto, no more squeaks walking past the table or coming out of the loo, and no more feeling of springing as you walk.

Hymie.
 

Abacist

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Oct 15, 2013
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Right. I haven't got any foam. The floor is dry above and beneath, with no sign of flexing. As far as I can tell, the floor consists of 3/4 ply, with just the standard lino on top. This is a 1992 Hymer coachbuilt. The soft bits are nowhere near to the hab door, but in two places in the centre corridor, one by the dinette, and one outside the loo door.
Instal some form of joist under the floor to provide additional support
 
Sep 12, 2012
1,404
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Wengen
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22,871
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Coachbuilt
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Since 2010
Right. I haven't got any foam. The floor is dry above and beneath, with no sign of flexing. As far as I can tell, the floor consists of 3/4 ply, with just the standard lino on top. This is a 1992 Hymer coachbuilt. The soft bits are nowhere near to the hab door, but in two places in the centre corridor, one by the dinette, and one outside the loo door.
Is there any yellow staining in those areas? :rolleyes:
 
OP
Tootles

Tootles

Funster
Deceased RIP
Sep 14, 2013
9,513
34,914
Lancaster
Funster No
28,093
MH
Coachbuilt
Exp
Was a newbie, now a Middie.
Instal some form of joist under the floor to provide additional support
What a great idea! Thanks....(y)(y) The front part of the floor is 'underpinned' by the original steel floor pan of the Fiat Panorama parent chassis, so that's not a problem, but I will certainly see if lateral cross bracing can be fitted, using maybe 3x2 timber.

Is there any yellow staining in those areas?
No Simb, this isn't the same MH you owned........:rofl::rofl:
 
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