PVC Outer Skin on wooden boat

[Punter42]

I have acquired a 6-9 seater wooden punt, for a bit of fun over the summer. A few patches had rotted through on the hull, the previous owner patched it by glueing a screwing new pieces of ply wood over the old hull, and likewise inside the boat, he then coated the outside hull in several layers of Bitchimen. The result of all of this is that the water is still coming into the boat at quite a rate except I can't tell where on earth it's coming from, it just appears to soak up through. I've included a picture taken a few seconds after it was put in the water, it is hard to see in the picture just how many puddles were forming, but within a few minutes it already had an inch of water.

I've reading some guides for building canoes with PVC and wondered if rather than find a workshop and rehull it, which I have neither the means nor the desire to do, would it not be possible to just buy a large roll of PVC, glue it to the outer hull and tack it on above the water line? The boat itself no longer needs to be waterproof as it's just acting as a frame. Any thoughts would be greatly appreciated.

 

[pmagowan]

You could but the boat would just rot away. Just take the patches off, strip it down and scarf new bits in where there was any rot. It is not that big a job and can be done with hand tools outside on a couple of good weekends. I did it with some rot in my boat and with a little bit of care you won't be able to see the repair at all. The pvc idea sounds like how you might create a raft or other bodge for a laugh but it won't last.

 

[Punter42]

Thank you very much for the advice. Essentially I just thought it allow me to use it with minimum effort for the summer and then should I decide to do it properly I could do so in the colder months or put it on eBay for someone else who fancies a project.

 

[Tranona]

Suspect you will find the whole floor is rotten and full of water. Remember water gets through the smallest places and bitumen won't stop it as it is probably not actually adhered to the rotten panels.

Boat does not look good enough to be worth replacing the bottom panels so probably save it for November 5th!

 

[fisherman]

Expanding foam loves the wet, if you can find the leaks.

 

[DownWest]

Some old sheets or canvas and lots of cheap oïl paint. Paint the hull, apply the cloth to the wet paint, then more coats to fill the weave, as few joins as possible.

 

[Punter42]

Thank you very much for this suggestion, I was considering doing something similar with epoxy paint. Would you recommend scrapping off the old coats of bitchimen to prepare it for this procedure? Or may I lay the sheet directly on to the prepainted hull?

 

[Tranona]

Don't waste your money trying to use epoxy on sodden wood - it simply won't stick. As I suggested earlier it is almost certain that the ply floor is rotten and that is why the bitumen is not sealing it.

The only solution is to cut out the rot and replace it. No amount of painting or trying to seal from the outside will stop water from seeping through.

 

[Punter42]

I'm sorry I don't think I described it very well. The rotten patches in the hull were all knocked through and dried out leaving several holes. Rather than just patching these holes the chap glued and screwed in to place sheets of ply to completely cover the old hull. Then bitchimen was painted onto the new dry sheets. However there must be gaps between the ply sheets that we missed and the bitchimen didn't fill because the water still comes through. But because of all these sheets and coatings I can't see where the holes are. So I need a complete coating solution.

 

[Tranona]

Then your problem is between the old parts and the new. No form of extra coating on the outside will fix it.

 

[pmagowan]

There are all sorts of bodges you can do including just putting the whole thing in a plastic bag but the only real solution is to take it apart and fix it properly. It is not that big a job and should be doable with materials from a B&Q, a few hand tools and a little DIY skill. You should be able to complete something reasonable in 1 or 2 weekends.

 

[andygc]

From your posts it is clear that you want to know if you can do a very quick fix so you can have some fun and then decide if you want to spend time doing a proper repair.

Of course you can. Buy the cheapest possible plastic tarpaulin that will cover the hull. Stretch it tight and staple along the gunwale (the top edge along the sides of the boat). Fold the ends as neatly as possible to fit the shape of the hull at bow and stern. Staple in place. Cut off the excess material. Job done in 15 minutes. Have some fun. At the end of the summer fix it properly or have a bonfire.