Floorboards

[Tom Richmond]

Hello,

 

What are people's views and experiences with real floorboards, as opposed to a plywood or other sheet material subfloor?

 

I am fitting out an old dutch barge, bilges are being treated as best I can, but are very corroded, and it would be good to be able to access them to check and maintain. The vessel has frames running across the beam every 30cm, which will work well as conventional 'joists'. My thought is to use fairly large section timber (perhaps new scaffold planks, for ease of availability?) and I am happy with a fairly rustic appearance. There would be no tongue and groove joint, and I would be able to lift a board wherever I wanted to inspect beneath it, if a board runs under a wall or kitchen or other part of a fit out I can cut it, but I will try and be sensible about where I site the joints.

 

My thought is to screw timber battens alongside every other, or even every third frame, to give me something to fix the boards down to. I am not sure how draughty they may be, but I would consider caulking the gaps (which could also look very nice) if it was necessary.

 

Thanks in advance for your collective knowledge!

[koukouvagia]

I used second hand floorboards (they came from the Tate!) laid on to transverse wooden bearers which were bolted to the steel cross-members.

 

The boards are tongue and groove, but the tongue is removed at various points so that I can lift sections out and inspect the bilges.

 

There will probably be some movement as atmospheric conditions vary - hence the T&G so there is no draught. Also remember to leave room for expansion at the edges otherwise the floor may warp.

 

[Tom Richmond]

I used second hand floorboards (they came from the Tate!) laid on to transverse wooden bearers which were bolted to the steel cross-members.

 

The boards are tongue and groove, but the tongue is removed at various points so that I can lift sections out and inspect the bilges.

 

There will probably be some movement as atmospheric conditions vary - hence the T&G so there is no draught. Also remember to leave room for expansion at the edges otherwise the floor may warp.

 

lining out owl -vg.jpg

 

Great stuff...

 

Yeah, just been chatting to a carpenter friend who suggested that reclaimed boards will tend to me more stable than new, as they've had time for the moisture content to settle...

[Robbo]

Hello,

 

What are people's views and experiences with real floorboards, as opposed to a plywood or other sheet material subfloor?

 

I am fitting out an old dutch barge, bilges are being treated as best I can, but are very corroded, and it would be good to be able to access them to check and maintain. The vessel has frames running across the beam every 30cm, which will work well as conventional 'joists'. My thought is to use fairly large section timber (perhaps new scaffold planks, for ease of availability?) and I am happy with a fairly rustic appearance. There would be no tongue and groove joint, and I would be able to lift a board wherever I wanted to inspect beneath it, if a board runs under a wall or kitchen or other part of a fit out I can cut it, but I will try and be sensible about where I site the joints.

 

My thought is to screw timber battens alongside every other, or even every third frame, to give me something to fix the boards down to. I am not sure how draughty they may be, but I would consider caulking the gaps (which could also look very nice) if it was necessary.

 

Thanks in advance for your collective knowledge!

If you screw battens length ways you could improve air flow, however I would add as much insulation as you can and use forced air flow (i.e. Some bilge fans to pull the air out from one end and vents at the other)

[Bee]

I'm guessing that the frames are 'angle iron' and that the nice useful flat side is what the plates are riveted to. Personally I would do just what you are suggesting but use tanalised timber or whatever preservative they use, roofing battens are cheap and if you can get everything level you might not need to fix the boards down at all. Grease is what they used to use on the bottom plates of barges but these days there are better alternatives, Waxoyl etc. Morris's of Shrewsbury do a wax and there are lots of other similar things. I was told by a Barge owner not to use old engine oil, 1) its awful stuff and smells horrible and 2) its acidic so not terribly good for steel.

[Sea Dog]

Careful with tantalised wood - brilliant when used correctly, but pop a mild steel screw in it and you can measure it's life in weeks.

[Tom Richmond]

If you screw battens length ways you could improve air flow, however I would add as much insulation as you can and use forced air flow (i.e. Some bilge fans to pull the air out from one end and vents at the other)

 

Headroom restricts my options somewhat. I have room for boards only above the steelwork.

 

But yes, some insulation (cellotex? What about the potential air gap?) is gonna go in I think.

 

 

I'm guessing that the frames are 'angle iron' and that the nice useful flat side is what the plates are riveted to. Personally I would do just what you are suggesting but use tanalised timber or whatever preservative they use, roofing battens are cheap and if you can get everything level you might not need to fix the boards down at all. Grease is what they used to use on the bottom plates of barges but these days there are better alternatives, Waxoyl etc. Morris's of Shrewsbury do a wax and there are lots of other similar things. I was told by a Barge owner not to use old engine oil, 1) its awful stuff and smells horrible and 2) its acidic so not terribly good for steel.

 

 

Yes, bilges will be treated in 'Bilge Grease', which is waxy stuff. I have seen warning against waxoyl elsewhere on this forum...

[Bee]

The usual advice is not to insulate below the waterline, possibly because it could soak up water lying in the bottom but I can't really think of a good reason why not so long as theres some sort of reasonable gap. You might struggle to get a worthwhile thickness in but if you can then celotex would be good. It is a really good thing to be able to get at the bottom. Personally I would be reluctant to buy an older boat if I couldn't lift a few boards, the floor really isn't a fit and forget item and planks of some sort are so much better than big sheets of ply (especially with laminate or something laid on top.) If you have a stove then inch dia. holes drilled in the floor in front of it will make the stove pull air in from the bilge.

[Robbo]

Headroom restricts my options somewhat. I have room for boards only above the steelwork.

 

I would use some kind of insulation between the metal and boards as you'll get cold spots on the floor which overtime you tend to get "marks" visible.

[Jrtm]

Brass or s/s screws are best but brass gets weak

[WotEver]

Axminster Tools now do a wide range of SS woodscrews including a starter set.

[Tom Richmond]

I would use some kind of insulation between the metal and boards as you'll get cold spots on the floor which overtime you tend to get "marks" visible.

 

Some sort of thin foam or rubber sheet / strips along the steel?

[nebulae]

I would advise against plywood. I have refitted a couple of (not very old) boats where rot has started in the shower area and once started has spread rapidly with the grain.A right pain trying to replace the boards without destroying the fit out. Old floorboards work well,but beware dry rot.I have this problem at the moment,so I am contemplating using 19mm compressed re-cycled plastic boards. We have used them succesfully for the floor of a cattle lorry. Has anybody used these yet?They are impervious to water,dont rot and can be sawn/nailed

[Jennifer McM]

We've got tongue and groove oak floorboards, I understand every metre or so one of the 'tongues' has been removed (you don't notice) so the floor can be picked up without any damage, in case we need to get underneath the floor.

[blackrose]

I would do what you originally suggested, except that on an old boat I'd prep the entire bilge area back to steel with angle grinders and wire wheels, vacuum, clean and spirit wipe and then apply a few coats of Jotamastic 87. There's absolutely no way I would be putting any kind of oil down there because I've seen cases where water gets underneath (and oil does tend to float on water). I can't say I know enough about waxoil to know if it floats on water? But anyway, prepping and painting with a good epoxy is just what I'd do because it would only need doing once.

By the way, I don't think you've mentioned ballast? Is there any, what is it and how does it sit on the steel?

Edited November 7, 2016 by blackrose

[Tom Richmond]

No ballast in bottom of bilge, poured concrete around the edge.

 

As i understand it, bilge grease/barge grease is more wax that oil. It is heated gently and applies as a liquid, then solidifies in place. I guess it is a little like blacking in the sense that it goes hand, but never truly dries.

 

I used jotamastic 87 on outside, both above and below waterline. It was great stuff. Not sure i want to use it inside though, as i am innevitably not going to get to every spot of rust in between the frames etc, and covering it up feels a bit like sweeping it under the carpet.

[blackrose]

No ballast in bottom of bilge, poured concrete around the edge.

 

As i understand it, bilge grease/barge grease is more wax that oil. It is heated gently and applies as a liquid, then solidifies in place. I guess it is a little like blacking in the sense that it goes hand, but never truly dries.

 

I used jotamastic 87 on outside, both above and below waterline. It was great stuff. Not sure i want to use it inside though, as i am innevitably not going to get to every spot of rust in between the frames etc, and covering it up feels a bit like sweeping it under the carpet.

 

Fair enough, if you can't get to the steel to prep it there's not much point using Jotamastic.

 

I don't like poured concrete ballast. Had it on a previous boat and water got between it and the steel.

[PaddingtonBear]

Fair enough, if you can't get to the steel to prep it there's not much point using Jotamastic.

 

I don't like poured concrete ballast. Had it on a previous boat and water got between it and the steel.

 

Well said, Your most important job will be to get rid of the concrete, very little point of using good blacking either in or out and leaving the concrete in. The concrete also indicates a shoddy boat building job as well IMHO

[Sweeny Todd]

Hi

 

We have used scaffold boards in out barge. We have tried different flooring types in our last boat (a narrowboat) but found that they all had their drawbacks. We figured the scaffold boards were designed to take the hammer and have been down now for around 6 months and have coped with everything that we have thrown at them during fitting out the barge, including getting very wet a few times when we were re building the cabin roof / deck. We fixed the boards in place using batons underneath which we screwed the boards to and have used cork inserts to fill the gaps in between whilst allowing for expansion. Gives a rather nice pinstripped effect too . We have sealed the boards with wax.

[Tom Richmond]

Thanks Sweeny Todd! That's really good to know.

 

Re the concrete. Thanks for your comments, I am well aware of the drawbacks, but it was discussed at length with my surveyor and decided it should remain in place. The balance of effort/cost to remove it against the potential benefits and overall value of the boat was deemed not worth it.

Sweeny Todd, can I ask how wide your barge is? (assuming you've laid boards lengthways?). Also, are you living aboard?

[Sweeny Todd]

Hi

 

We have laid our boards length ways. Our barge is 17' 6" wide so wider than many. We do live aboard the boat (2 adults, 1 large dog and a cat). As the boat is still a work in progress the boards are getting plenty of hammer but are standing up to it. As for the concrete, I agree with your surveyor. Having been on quite a few of the older barges, many of them have concrete in one area or another so not unexpected to find some.

[Tom Richmond]

Yeah, it was an old working boat (built in Holland 1940) which got topped off and turned into a liveaboard in the 80s. I am sure when they poured the concrete it was the easiest cheapest way to get the boat ready to haul coal or whatever it needed to do, and they weren't so concerned with it's longevity!