Cause of Rot?

[SHUG]

Am I right that fresh water can cause rot and that salt water does not?

I have an open wooden boat which is a rain trap but I periodically flush out the bilges with sea-water in the hope that this will prevent rot in the bilges.
I see that there are water soluble wood preservatives on the market would I be better using some of that periodically.
No rot so far after thirty years but its always a worry with a wooden boat.

 

[Wooden Boat Fittings]

Hi Shuggie,

I reckon the jury is still out on this one, and possibly will be forever. Some wooden boaties swear that salt helps prevent rot, others pooh-pooh the whole idea and says that it's the dampness that does it whether there's salt present or not.

I know that some old sailing ships had salt shelves built into the structure to hold bags of salt where they could deliquesce and keep the atmosphere saline. I reckon there was probably a reason for that.

Personally, I go with the salt theory myself, but I've been howled down more than once by the anti-religionists. I was always glad that I sailed Aileen Louisa in saltwater, but had I been restricted to fresh I certainly would have salted the bilges from time to time.

Mike

 

[BlueLancer]

I would concur that Freshwater causes more problems than Saltwater. The main cause of rot on my timber cruiser was from the ingress of rainwater through a leaking deck. The bilges hold a small amount of water which does not seem to be a problem.

 

[Eyore]

Have to say I go with the salty water being ok and fresh being bad theory myself, especially when it comes to deck/superstructure leaks as mentioned above. If I was berthing in fresh water I would certainly sprinkle salt in the bilges.

 

[chinita]

If salt water causes rot my boat would have disintegrated ages ago with the amount I have swilled over the decks and through the bilges.

 

[chinita]

Have to say I go with the salty water being ok and fresh being bad theory myself, especially when it comes to deck/superstructure leaks as mentioned above. If I was berthing in fresh water I would certainly sprinkle salt in the bilges.

Don't waste the salt - the freshwater gribble will get her anyway!

 

[Kukri]

Umm.

Wood which is thoroughly saturated with water won't rot, whether that water is fresh or salt.

Wood that is dry to its natural state of equilibrium won't rot either.

Damp wood is what rot needs. Wet rot can only spread in damp timber; dry rot carries its wetness with it, hence the name, but has to start in a damp place.

Salt timber stays damp.

I am a heretic and I am with L Francis Herreshoff in saying that at the end of a season the best thing you can do is to put a fresh water hose through your boat, inside and out, obviously after removing the soft furnishings, and then let her dry in the breeze before you put the winter cover on. By flushing out all the salt you will stop the timber from staying damp.

An open boat is OK unless she sits for a long time with rain water in her bilges - you'll notice that it is the area "between wind and water" where rot tends to start, because the timber there is damp but not saturated.

 

[SHUG]

Thanks for the comments. The summary seems to be that I should salt the bilges in season and dry out in the winter after a fresh water rinse to avoid dampness.
No comment on introducing water based preservatives into the bilges.For example: http://www.wickes.co.uk/Products/Gardens/Garden-Timbercare+Wood-Preservatives/Water-Based-Shed+Fence-Treatment/c/1000772

 

[Kukri]

Thanks for the comments. The summary seems to be that I should salt the bilges in season and dry out in the winter after a fresh water rinse to avoid dampness.
No comment on introducing water based preservatives into the bilges.For example: http://www.wickes.co.uk/Products/Gardens/Garden-Timbercare+Wood-Preservatives/Water-Based-Shed+Fence-Treatment/c/1000772

No need for that. And remember - your bilge water goes overboard and fishes have to drink it!

 

[PhillM]

So what does the forum think about hosing off the boat in freshwater after sailing?

I've tended to do this about once a month, not every time. Just to try to keep the salt off the boat and of course to keep her generally clean.

I find it a useful way to try to spot and fix deck and coachroof leaks too.

 

[LittleShip]

I leave the salt on the boat, give her a scrub down with a wax polish every now and then. I dont wash off the salt whist she is in the shed over the winter period as I think it helps keep some moisture in the wood.

I remove water (salt) from the bilges when she is ashore and I clean off salt deposits from the joints in the bilge after launching for the season.

Tom.

 

[Searush]

The boats that rotted most at Conway, were those under the trees. Seawater preserves timber, that's why wrecks last so long, and logs float for years until waterlogged & sink, but a handful of twigs lying in rainwater soon grow mould & start rot on the decks.

 

[Rosie1963]

Rot need not need water on it to start it; Just dampness will do. Condensation in the cabin is a great tell tale sign of a damp - get ventilators fitted! My hull has been lined in plywood on the inside and I see, rather unsurprisingly, mold on all the inside surfaces of plywood.

Re: washing in fresh water. Rosie has a drain plug so this can be done with water draining out by gravity when ashore. In the design spec from one Humphrey Barton, so I wont argue with that!

 

[SHUG]

Thanks for your responses.
Obviously ROT is close to the heart of any wooden boatowner.
The message I am getting is that DAMP is the villain of the piece and that ventilation is the key to wood preservation.

 

[chinita]

Absolutely.

Ventilation is it.

You know your ventilation is right when you have spiders on board; spiders hate damp!

 

[chinita]

Absolutely.

Ventilation is it.

You know your ventilation is right when you have spiders on board; spiders hate damp!

 

[Kukri]

Thanks for your responses.
Obviously ROT is close to the heart of any wooden boatowner.
The message I am getting is that DAMP is the villain of the piece and that ventilation is the key to wood preservation.

As they say in my wife's country, KORECK!

 

[chinita]

"Fink else?"