Steel boat - headlining advice

[Valhalla1]

Hello, I have a Dutch Steel Cruiser and am in the process of re-lining the sides of the main cabin. There was carpet which disintegrated so not keen on doing that again. Was thinking of foam backed vinyl - anyone used this straight onto steel sides? Any other ideas?? Thank you ?

 

[Tranona]

Perhaps best not to stick anything direct to the steel, but to build a framework inside for panelling, leaving a gap that can be used for insulation. That is how they usually finish the inside of steel narrow boats.

 

[harvey38]

Evening Valhalla, do a search and you'll find plenty on the subject although I'm not sure that sticking onto steel would work too well. A couple of super talented members on here have built steel hulled boats so will be better able to guide you.

 

[JOHNPEET]

I don’t think that the foam backed vinyl would have sufficient insulation value to keep the interior of the boat warm in cooler weather, cool in warmer weather or keep condensation at bay. My approach was as follows - four additional coats of epoxy primer onto the pre blasted and primed steel after drilling 10mm holes in the frames and stringers ready to accept timber grounds. The timber grounds were fixed to the steel using 6mm stainless bolts, using a shouldered nylon bush in the 10mm holes in the frames in order to prevent the bolts from damaging the primer and coming into direct contact with the steel. Then 30mm sheets of rigid foam insulation were cut and bonded to the hull plating using expanding foam in such a way to ensure that there were no voids behind the sheets of insulation. The foam was trimmed and all joints were sealed with self adhesive aluminium tape to make the insulation as air tight as possible. 9mm ply was then cut and fitted over the timber grounds to completely line the interior of the boat. After installing all of the interior bulkheads and partitions etc, I then lined all of the ply with a further layer of 4mm oak veneered ply using contact adhesive so no fixings are visible. You could use the foam backed vinyl at this point in lieu of the 4mm oak. Use waterproof pva adhesive to bond the foam backed vinyl onto the ply. Use an A2 spreader for the pva. I used foam backed vinyl bonded onto 4mm ply for the deck head panels. I can provide some photos of all of this if i5 would help Or search out my build thread!

 

[Refueler]

Foam Backed Vinyl ..... lovely stuff - till foam powders away !!

As others say - doubt any lining is good stuck direct to the steel.

Just thinking about it ... I would be inclined to look at floor insulation ... you can get it in various thicknesses from about 2mm and up. That can be applied with carpet spray adhesive between battens. The top lining then can be anything such as Van Lining (I'm using this to replace Foam Backed Vinyl in my GRP boat) ... or whatever.

Just thoughts ... but basically - I would not use Foam Backed Vinyl.

 

[Stemar]

Foam Backed Vinyl ..... lovely stuff - till foam powders away !!

That was my thought, too. ISTM that there are far more boaters who swear at the stuff than swear by it.

I rather like Johnpeet's plan. If you don't want a veneer finish, just paint the ply with a mould-resistant kitchen and bathroom paint.

 

[PCUK]

I used foam back cord carpet glued onto the steel. Never any condensation and still in good condition after thirty years.

 

[justanothersailboat]

I'm begging you here, please not foam backed vinyl. Someone will get stuck with the job of ripping out the horrid decaying nightmare it inevitably becomes.

(guess what I've been doing this winter?)

 

[Refueler]

I'm begging you here, please not foam backed vinyl. Someone will get stuck with the job of ripping out the horrid decaying nightmare it inevitably becomes.

(guess what I've been doing this winter?)

Guess who is dreading doing the main cabin after completing forecabin ......

I have to say though - it wasn't quite as bad as many have made out ... I decided not to go the whole sanding and grinding route ... I scraped as much as possible till reasonably level and no dust / flake left - then hoped van lining would take. It took well and has shown no signs of peeling - despite my reduced preparation.

 

[justanothersailboat]

Thanks Refueler, good to know it's not an automatic disaster if the subsequent sanding-down is less than exhaustive! Fingers crossed yours stays good.

The sinking feeling when one admits it has to go, then peels it back and unveils the brown-green-grey filth that instantly covers everything, is bad enough - possibly worse than the work afterwards. And l can't even tackle the forecabin this year...

 

[geem]

I don’t think that the foam backed vinyl would have sufficient insulation value to keep the interior of the boat warm in cooler weather, cool in warmer weather or keep condensation at bay. My approach was as follows - four additional coats of epoxy primer onto the pre blasted and primed steel after drilling 10mm holes in the frames and stringers ready to accept timber grounds. The timber grounds were fixed to the steel using 6mm stainless bolts, using a shouldered nylon bush in the 10mm holes in the frames in order to prevent the bolts from damaging the primer and coming into direct contact with the steel. Then 30mm sheets of rigid foam insulation were cut and bonded to the hull plating using expanding foam in such a way to ensure that there were no voids behind the sheets of insulation. The foam was trimmed and all joints were sealed with self adhesive aluminium tape to make the insulation as air tight as possible. 9mm ply was then cut and fitted over the timber grounds to completely line the interior of the boat. After installing all of the interior bulkheads and partitions etc, I then lined all of the ply with a further layer of 4mm oak veneered ply using contact adhesive so no fixings are visible. You could use the foam backed vinyl at this point in lieu of the 4mm oak. Use waterproof pva adhesive to bond the foam backed vinyl onto the ply. Use an A2 spreader for the pva. I used foam backed vinyl bonded onto 4mm ply for the deck head panels. I can provide some photos of all of this if i5 would help Or search out my build thread!

Excellent advise on how to do the insulation properly. So many steel boats miss out this vital process and suffer an early demise due to internal corrosion. I would go as far as to say it would be even better to use some of the proprietary waterproof membrane systems onto of the insulation layer to provide a long-term moisture barrier. I have seen the aluminium self adhesive foil tape fail after a few years.

 

[JOHNPEET]

Whilst I appreciate that where foam backed vinyl has been bonded directly to a hull it can be a nightmare to remove and prepare the substrate for the subsequent lining material, I still think that the vinyl has a role to play in the correct application! As I mentioned in a previous post, I have used it on my deck head panels with good effect (at least I think so anyway!). All of my deck head panel are easily removable and so should the foam break down at some point in the future, if removal of the foam from the panels is found to be overly difficult, I can use the panels as templates for new!
As nothing lasts forever, I can imagine some of the suggested alternatives being quite difficult to replace in the future also should they become tired, stained or damp.
One of the factors that influenced my choice of finishes, is that I wanted all surfaces within the boat to be wipe clean.

 

[Valhalla1]

Whilst I appreciate that where foam backed vinyl has been bonded directly to a hull it can be a nightmare to remove and prepare the substrate for the subsequent lining material, I still think that the vinyl has a role to play in the correct application! As I mentioned in a previous post, I have used it on my deck head panels with good effect (at least I think so anyway!). All of my deck head panel are easily removable and so should the foam break down at some point in the future, if removal of the foam from the panels is found to be overly difficult, I can use the panels as templates for new!
As nothing lasts forever, I can imagine some of the suggested alternatives being quite difficult to replace in the future also should they become tired, stained or damp.
One of the factors that influenced my choice of finishes, is that I wanted all surfaces within the boat to be wipe clean.View attachment 149748View attachment 149749View attachment 149750View attachment 149751

Gorgeous!

 

[Valhalla1]

Thanks everyone for your responses and taking the time to reply, truly appreciate it. Have decided against the foam backed vinyl now! Do you think the foil bubble wrap stuff first as insulation and then just plain vinyl will work? As Johnpeet mentioned, I really wanted something wipe clean so like the idea of the vinyl. Thanks.

 

[Refueler]

Thanks Refueler, good to know it's not an automatic disaster if the subsequent sanding-down is less than exhaustive! Fingers crossed yours stays good.

The sinking feeling when one admits it has to go, then peels it back and unveils the brown-green-grey filth that instantly covers everything, is bad enough - possibly worse than the work afterwards. And l can't even tackle the forecabin this year...

My 'trick' was to have a vacuum cleaner nozzle playing as It pulled old vinyl away ... it makes job longer - but reduces the spread of that dust ..... plus a simple dust mask is then sufficient.

Originally I had planned to follow many Youtube examples and had drill with sanding gear ready .... but once I saw reality and that most of the crud actually flaked or fell away .... left drill and gear in the bag.

Pulling old down :

Surface once old vinyl away ... before general brush off ...

After general brushing - still looks bad - but in fact was OK for new application ..

Old vinyl used as rough template on Van Lining :

Van lining in place ....

Just that one seam that didn't lay in and 'mesh' as well as other side ...

Apologies to original Poster ... but maybe it can help to reduce that dread of doing the job !! I have to say that once I had that lining in place - I sat back and felt proud !!

 

[Refueler]

OK - I have to accept that Van Lining will not be 'wipe clean' as vinyl ... but having already had to 'clean' marks from it - a damp rag with tiny bit of washing up liquid did the trick. For anything more - I would expect to use a carpet cleaning solution - one that foams .... and then wipe away ...

 

[boatmike]

Lots of good advice here but I would second the advice not to stick anything direct to the steel. There are many ways of insulating the hull but the easiest is to first ensure that you have a good corrosion resistant finish on the hull itself followed by adding wooden battens which can be held in place by sikaflex and screwing light plywood to them to create an airgap between the hull and interior. You can then finish this with anything you choose including vinyl, carpet, or perhaps use wood veneered ply and varnish. This will not only be more attractive long term but provide insulation and reduce condensation.

 

[MisterBaxter]

It's really important to prevent warm, moist cabin are from contacting the steel; in an ideal world you want at least 30mm of foam insulation or the equivalent of other types; and ideally you want to be able to remove any section to access the interior steel hull easily, but some feel that this can be compromised on if the first two are 100%, as in spray foam applications.
Foam backed vinyl would only achieve the first one, so I wouldn't use it myself.
Johnpeet's process looks excellent although as mentioned an additional waterproof membrane might be worth adding, behind the ply lining but on top of the insulation.

 

[Refueler]

IMHO as already posted ... 3 - 6mm floor based closed cell insulation sheet ... Depron or similar .... will give good water resistant insulation against the steel - especially if a good resin based protective paint applied first.
Battens applied between panels of foam sheet to give fastening for whatever you consider on top of the foam sheet.

 

[JOHNPEET]

It's really important to prevent warm, moist cabin are from contacting the steel; in an ideal world you want at least 30mm of foam insulation or the equivalent of other types; and ideally you want to be able to remove any section to access the interior steel hull easily, but some feel that this can be compromised on if the first two are 100%, as in spray foam applications.
Foam backed vinyl would only achieve the first one, so I wouldn't use it myself.
Johnpeet's process looks excellent although as mentioned an additional waterproof membrane might be worth adding, behind the ply lining but on top of the insulation.

I sealed all joints in the insulation and the insulation to the timber grounds etc, I don’t doubt that a further vapour barrier would improve things further.