Medium-density fibreboard, in a boat ??

[Javelin]

We recently refitted a well known brand of boat that had a flooding problem due to a dodgy sea-cock.

During the dismantling of her interior we were somewhat astonished to see that most of the internal woodwork was made of cherry faced MDF.
We contacted the builder who told us proudly that this was a waterproof variety of MDF and that many manufacturers use it.

Not quite sure what makes this mdf waterproof as all the panels soaked up the water like a sponge.
The flood was around 6" deep over the floor but the water stains on the mdf could be seen almost to the roof and all the panels up to around three feet up had expanded by at least a third in width.

I've seen small sections of veneered chipboard in some Jeanneau's but I never thought I'd see MDF in a boat.

 

[sailorman]

We recently refitted a well known brand of boat that had a flooding problem due to a dodgy sea-cock.

During the dismantling of her interior we were somewhat astonished to see that most of the internal woodwork was made of cherry faced MDF.
We contacted the builder who told us proudly that this was a waterproof variety of MDF and that many manufacturers use it.

Not quite sure what makes this mdf waterproof as all the panels soaked up the water like a sponge.
The flood was around 6" deep over the floor but the water stains on the mdf could be seen almost to the roof and all the panels up to around three feet up had expanded by at least a third in width.

I've seen small sections of veneered chipboard in some Jeanneau's but I never thought I'd see MDF in a boat.

would you care to name the German manufacturer

 

[lw395]

I had a kettle fail to switch off in our kitchen. The MDF above it swelled to double thickness in one place, due to the steam.
The swelling eventually went down, you cannot see any damage now.

It's how you get a boat down to the price.

 

[sailorman]

I had a kettle fail to switch off in our kitchen. The MDF above it swelled to double thickness in one place, due to the steam.
The swelling eventually went down, you cannot see any damage now.

It's how you get a boat down to the price.

Yes & photo the veneer onto it

 

[30boat]

would you care to name the German manufacturer

Why not tell us what make the boat is?

 

[sailorman]

Why not tell us what make the boat is?

The OP is better informed

 

[planteater]

Veneered MDF is fine in a dry environment - got loads of it in our house. I guess it's down to whether you regard the interior of a yacht as a dry environment. Water coming in from from dodgy sea cock is probably going to knacker something.

 

[sailorman]

Veneered MDF is fine in a dry environment - got loads of it in our house. I guess it's down to whether you regard the interior of a yacht as a dry environment. Water coming in from from dodgy sea cock is probably going to knacker something.

i believe that mdf is a banned material in the use due to carcinogenic properties

 

[Lakesailor]

We used some mdf to face a sturdy stud wall for fixing tiles to.
What a mistake.
It was in a ensuite and only took about 6 months to absorb damp and start smelling like dead fish.
Had to tear it out.

 

[prv]

I needed some cherry-faced ply to make a new bulkhead in Ariam, and could not find it available from stock anywhere in the country. Lots of people wanting to sell me cherry-faced MDF though.

In the end I had to get Robbins to make me a sheet specially (laminate some of their cherry veneer onto a sheet of WBP). No way I'm putting anything other than decent ply or solid hardwood in any boat I own.

Ariam is old enough (1998) that the bulkheads and furniture are ply, but it doesn't surprise me for a moment that newer boats are MDF.

Maybe this is the answer to the "old GRP boats last forever" problem? The hulls will still be around, but the interiors will be soup.

Pete

 

[saxonpirate]

Maybe this is the answer to the "old GRP boats last forever" problem? The hulls will still be around, but the interiors will be soup.

Pete

Brilliant... that's gotta be quote of the month

 

[Daydream believer]

i believe that mdf is a banned material in the use due to carcinogenic properties

Well nobody told me. When i had my joinery business i used to buy lorry loads of the damned stuff.i hated it
HSE advised me that there was no problem with it & the dust produced was non hazardous. Which is good because my workshop often got covered in the dust if an extractor fan or bag burst
The biggest problem with its use on a boat would be its weight followed by its total failure at the sight of water
However, there are moisture resistent ( note note dunk in the drink resistent) & exterior grades
I never used much exterior grade but seem to recall it had a greasy surface making laminating difficult

Re buying veneered panels
If they are still going then Eden's in Kent will supply from stock pre veneered boards & for a boat Brunezeel ply is the best
I believe James Latham will do the same ( oh how one soon forgets when retired)
There are loads of firms ( shawyers in east london for starters) who will purpose veneer a sheet of ply for you but you need to ensure that the glue they use is a waterproof glue
Most veneerers used to use a spray on neoprene glue or a PVA adhesive , not all of which is waterproof

 

[oldsaltoz]

I suspect there is a lot of this rubbish on boats than we believe. I was floored I discovered this had been used in "light weight" 28 footer a couple of years ago, it was the bunk sided in the sallon and was supporting the hull shape, well almost, as the bottom 4 inches was a nice veneer on the outside but mud on the inside. Replace with ply and new veneer, not cheap but safer and lighter.

Good luck and fair wingds.

 

[dleroc]

Well nobody told me. When i had my joinery business i used to buy lorry loads of the damned stuff.i hated it
HSE advised me that there was no problem with it & the dust produced was non hazardous. Which is good because my workshop often got covered in the dust if an extractor fan or bag burst
The biggest problem with its use on a boat would be its weight followed by its total failure at the sight of water
However, there are moisture resistent ( note note dunk in the drink resistent) & exterior grades
I never used much exterior grade but seem to recall it had a greasy surface making laminating difficult

Re buying veneered panels
If they are still going then Eden's in Kent will supply from stock pre veneered boards & for a boat Brunezeel ply is the best
I believe James Latham will do the same ( oh how one soon forgets when retired)
There are loads of firms ( shawyers in east london for starters) who will purpose veneer a sheet of ply for you but you need to ensure that the glue they use is a waterproof glue
Most veneerers used to use a spray on neoprene glue or a PVA adhesive , not all of which is waterproof

Not quite so I'm afraid. Hard and soft woods all have exposure limits for dust and that for hard wood is more stringent. The original rumours about MDF being banned etc due to possible carcinogenic causes originated from the USA where the rumour was that it had been banned. MDF contains formaldehyde and some of the boards were not properly dried after manufacture and when used would give off high levels of this chemical. When dry the remaining risk is just one of dust exposure.

 

[rob2]

It's how you get a boat down to the price.

Sounds more like how to get a boat down to the bottom! If they think that adequate what other fatal stupidities have they built in? Vot a bunch of Vankers!

Rob.

 

[maby]

I'm pleased to see your report - when I mentioned the use of MDF in the construction of modern boats on another thread recently, nobody believed me. It is a way of keeping construction costs down and probably does not detract excessively from the boat provided it is only used in non-structural contexts. If you get enough water into your boat to destroy an MDF cupboard door, it is probably one of your lesser problems!

 

[AngusMcDoon]

I have foam cored plywood for interior panels. I imagine it's more capable of taking a soaking than MDF, but at $400 a sheet for 8' x 4', I would hope so too!

Oops! It's a bit of a big pic. Didn't look like that when I copied the link.

 

[snooks]

Not all MDF is the same, just like not all plywood is the same or chipboard or wood.

I've seen faced MDF on many boats, although some cover it better than others...even on some high end Swedish boats it's there.

However this is not your bog standard stuff you get from B&Q. It's moisture resistant, the same way chipboard for floors is treated and green coloured, so is treated MDF.

This stuff won't suck up water and absorb water, neither will it delaminate when it get wet. therefore it's perfectly fine to find on boats....Panic over

 

[sailorman]

Not all MDF is the same, just like not all plywood is the same or chipboard or wood.

I've seen faced MDF on many boats, although some cover it better than others...even on some high end Swedish boats it's there.

However this is not your bog standard stuff you get from B&Q. It's moisture resistant, the same way chipboard for floors is treated and green coloured, so is treated MDF.

This stuff won't suck up water and absorb water, neither will it delaminate when it get wet. therefore it's perfectly fine to find on boats....Panic over

Well that ok then

 

[Daydream believer]

Not all MDF is the same, just like not all plywood is the same or chipboard or wood.

I've seen faced MDF on many boats, although some cover it better than others...even on some high end Swedish boats it's there.

However this is not your bog standard stuff you get from B&Q. It's moisture resistant, the same way chipboard for floors is treated and green coloured, so is treated MDF.

This stuff won't suck up water and absorb water, neither will it delaminate when it get wet. therefore it's perfectly fine to find on boats....Panic over

That is not quite so
Mr grade is or uses where there may be some moisture ie kitchen unit carcasses
Not a boat or even a shower partition wall for that matter
Plus a lot depends on what glue is used to stick the veneer to it
Some veneers would just peel away in a high moisture environment
I could have shown you loads of so called mr chipboard floors that failed during the construction phase