On Thu, 24 Jul 2008 13:43:29 -0700 (PDT), "
wrote:

Hi all,
On the assumption that my boat stays above the waves long enough,
my next job is to put in floors. I've landed myself the job of
removing a library full of oak shelving which should do the job
nicely, but I;m not too sure what the best way of joining them
together or sticking them down would be - I've laid permeable
bubblewrap style insulation under the floor (over the ribs/joists, off
the bottom of the hull) and I could do with advice as to what to do
next - as I see it my options include:
- nail/screw the planks to the joists through the insulation
- nail/screw/glue the planks to crossways bits of wood lying on top of
the insulation (the whole floor would not be attached to the joists,
but this is a predominantly inland waterways boat, so it shouldnt get
too shaken up)
- biscuit joint the floor together into one big slab
- get the planks tongued and grooved and clip them together

My woodworking skills have not had a chance to develop yet, so nothing
too technical would be good.

thanks in advance,

Jim Potter

Any time you do anything to a steel boat your first thought should
always be RUST, and most steel boats rust from the inside out.
One of the more common problems with steel boats is wood to metal
joints holding water and the metal corroding and the wood rotting.

I question what good bubble wrap is going to do under the cabin sole
(floor). Is this heat insulation? Prevent condensation?

I'm not a steel boat builder so don't want to be too specific but what
I have seen is the cabin sole bonded and screwed down to the steel
beams, usually with Sikaflex or 3M 5200 and stainless screws.
Depending on the location flush hatches are used to allow access to as
much under deck space as is possible - you do want to be able to
inspect for rust and clean and paint if at all possible as well as the
usual stowage.

I think I would recommend a plywood sub-flooring covered by some sort
of finish lumber. your oak for example. If you just lay down oak
boards they will undoubtedly shrink leaving cracks for dust and dirt
to filter down into the bilges.

You might try contacting Roger Long over in rec.boats.cruising. He
designs metal research boats and may have some ideas about laying wood
decks on steel (although I believe he works mainly with aluminum).

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)