Deck Leaks!

chal

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I was going to add this to the "Teak Decks!" thread but any classics forum needs a more general Deck Leaks thread anyway (perhaps the software powering classics forums should have built-in threads to save us the trouble of starting threads for varnish, stockholm tar, leaks, etc etc). And, my deck isn't teak ;(

My deck is now 75 years old and is pine planks, 1 inch thick. When I bought the boat, the wood itself was in quite good condition but the screws were not, and the sikaflex no longer adhered to the planks in a number of places. The surface was just bare wood. Overall, it looked ok: I think the comment about teak decks looking fine scruffy and suitable for royalty when clean probably applies to any natural wood. However, when it rained, it rained almost as much below the deck as above, and something absolutely had to be done about it.

I am restoring the boat on a strict budget (it actually costs me a lot more than I first intended, even trying to be strict) and I also have limited time. I was very lucky because where I was doing the work, someone was building a boat from scratch (the big lugger I put a link to in the "Designing and building a modern wooden classic" thread); he was just the nicest and most helpful person you could ever hope to meet and gave me a lot of advice, lent me some tools, etc, and under his guidance I did the following.

First, I screwed the deck down. I understand Tillergirl's point about this taking 10 years to replace the screws and I did not do that. The original screws were put into the beams in a "top left, bottom right" pattern, so I put new screws in bottom left and top right. Where the old screws were exposed and the wood had gone soft I scraped it out, then filled all the exposed screw recesses with cheap Trago Mills sikaflex substitute. It took over a thousand screws and I did not have time to put little wooden plugs in every new hole plus most of the old holes. I reckon about 90-odd percent of my screws went into sound timber so I'm taking the beams on trust. I then repaired the sikaflex: I didn't remove it all but cut out areas where it was no longer adhering to the deck, and filled the holes with more of the Trago gunk (£3 a tube, and I used a lot of tubes).

My plan at that stage was to sand the whole lot down and apply Coelans (once again, a cheaper brand) as that would tend to run into any cracks and both seal any remaining small leaks and add UV protection to the cheap-o-flex. It looked pretty good, but I hadn't realised that that sort of finish goes cloudy when wet, so overall it mostly looked a bit peculiar. In the end, I decided to go for a solid colour, and the decks are now green, and swmbo and I think they look pretty good.

The final result is that they do keep most of the water out: we get the odd drip although that's mostly condensation from the portholes. Last summer of course when everything went a bit mad and there was a strange big hot yellow thing in the sky for a change, the planking shrank a bit and the leaks started again, albeit on a much smaller scale than before. Captain Tolley thankfully sorted them out. We repaint the deck annually and it does pretty much do the trick (the paint is expensive though).

Apart from sharing experiences and getting a bit of early morning typing practice, a point of this thread is to pose a question too, and that is the old chestnut of: is it really possible to stop wooden decks leaking???

Where swmbo and I differ about the deck is that I think that if I ever had some spare money - however unlikely that might be - I'd like to replace the deck and would probably go for plywood with a glass mat covering, using the woven glass that hopefully would end up looking like canvas when painted. Chal is what might be called a "smack yacht" and canvas deck covers would have been pretty common on such boats. I would hope this would finally stop all the leaks and reduce maintenance to a lick of normal deck paint when it looked worn. Swmbo on the other hand thinks this would be sacrilege: we would loose the pattern of the planks which is still clearly visible, and old wooden boats are supposed to have the odd leak.

What does the panel think?

This is what the deck looks like now (actually at its worst after last summer's heatwave, so you can see some caulking mess around a few of the seams):

deck_zps0cf4d7fb.jpg


and this is what is underneath (at the end of the repair process):

deck2_zps9fe4010b.jpg
 
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DoubleEnder

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My decks are newer than yours, but are similar construction. Deck planks screwed in to deck beams, and sikaflex seams. The planks are teak, the deck is now about 7 years old and it doesn't leak at all (touch wood). So it is certainly possible to have a traditionally constructed deck that keeps the water out. The ply/glass method works but is not without it's problems: one advantage of traditionally built decks is that if you have a leak, you know about it and give it attention. Ply/glass or ply/teak can hide the presence of a leak until a lot of damage has been done.... the water migrates horizontally to the edge of the ply, where it starts to rot expensive bits of the boat.

I don't know about Coelan, have never used it.

I'd say stick with what you have. New decks would be really expensive and may be no better, might even be worse. If you can keep up the paint, and maybe give them a bit of a soaking during heatwaves, I think it is healthy
Graham
 

NormanS

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When I had a big wooden boat (60' converted fishing boat), she had 2" Oregon Pine decks. I completely re-caulked the decks with oakum, and payed them with pitch. In normal use there were NO deck leaks. Like you, I painted the decks, but I just made up a semi-gloss mixture of light grey, stirring some sand into the paint, to make it non-slip. I made it a light grey, to try to stop it getting too hot in the sun, and if at all possible, cooled it with the deck-wash hose. Occasionally, after hard frost in the winter, some dampness would appear. You wouldn't really call it a leak, but a nuisance just the same. Presumably there was some damp in a seam, which would freeze, swell, and then when it thawed, would make its presence felt.

I think the only real recommendation that I would make would be to consider painting with a lighter colour, to try to cut down the temperature caused by the sun. Am I correct in supposing that your deck is not actually caulked at all, but merely payed with mastic?
My deck planks were all "quarter" sawn, which meant that the grain was mostly vertical. I notice that yours are not. This may result in more shrinking and swelling.
 

LittleShip

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I always check around my deck after rain as when the decks start to dry any loose seams will stay wet.

Then it's out with the craft knife, sharpened screwdriver, sandpaper, magic stuff to help Sikka stick, a tube of black ****e and sore knees for the evening.

The gin makes it all worthwhile.:rolleyes:

Looking after a deck is easier than trying to get it back in good order after years of neglect.

Tom.
 

chal

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I think the only real recommendation that I would make would be to consider painting with a lighter colour, to try to cut down the temperature caused by the sun

we started with light grey ourselves for that very reason, but it was perpetually dirty and as summer after summer has been a washout we changed to the dark green. mostly not a problem and it looks better (we think)


Am I correct in supposing that your deck is not actually caulked at all, but merely payed with mastic?

yes as far as I could tell
 

IAN JACK

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i have the same decks as yours, 2" Oregon Pine, also quarter sawn, on a 55 footer. some previous owner had glassed them and they were a mess, we stripped the glass off, very easily i was surprised to find, and we are in process of caulking(oakum) and paying with Sikaflex, we intend to leave them natural if possible and i wonder if anyone has recommendations as to what preservative should be used so that the wood does not darken or get slippery when wet. have heard Deks being advised,also Sikkons Ceetol.
any thoughts ??
 

chal

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i have the same decks as yours, 2" Oregon Pine, also quarter sawn, on a 55 footer. some previous owner had glassed them and they were a mess, we stripped the glass off, very easily i was surprised to find, and we are in process of caulking(oakum) and paying with Sikaflex, we intend to leave them natural if possible and i wonder if anyone has recommendations as to what preservative should be used so that the wood does not darken or get slippery when wet. have heard Deks being advised,also Sikkons Ceetol.
any thoughts ??

Cetol is now called Woodskin afaik after International did some sort of brand re-organisation. I like it (see the Varnish thread) but I don't think I'd put it on a deck: I think it would wear off too quickly and also be too slippery. My deck was natural, no coating at all, and was fine - showed the dirt less than any paint and reasonably non-slip when wet. Only painted now as part of water-tightening, which you might not need. Last point is that Woodskin now only available in teak colour.
 

IAN JACK

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Cetol is now called Woodskin afaik after International did some sort of brand re-organisation. I like it (see the Varnish thread) but I don't think I'd put it on a deck: I think it would wear off too quickly and also be too slippery. My deck was natural, no coating at all, and was fine - showed the dirt less than any paint and reasonably non-slip when wet. Only painted now as part of water-tightening, which you might not need. Last point is that Woodskin now only available in teak colour.

thank you for your very helpful reply,i can see i will have some rethinking to do with regard to preservative but your decks seem to be ok without it. thanks again
 

Kukri

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I'd like to report a success.

In 1995 I had owned Mirelle for 11 years and the decks, originally 1 1/4" teak secret nailed with iron dumps to oak beams by Claude Whisstock, later screwed down by Ernest Nunn, had leaked all the time. My sister knew Leena Reekie who knew a barge owner who had used some magic stuff called Coelan on his foredeck seams and had enjoyed, for the first time in his ownership, a drip free night in his bunk, so I discussed it with Alan Staley and we decided to give it a go.

At that time Coelan was almost unknown in Britain.

We sanded the decks, reefed out, recaulked and payed (with Sikaflex DC) the seams and after checking with a moisture meter* primed and applied six full coats of Coelan.

This resulted in an attractive finish but when we went to sea we found we had made ourselves a skating rink, and we were worried about UV degrading the Coelan, so we painted over it with Blakes' nonslip deck paint.

The boat was, honestly, bone dry below from 1995 until I sold her last November.

(The new boat, built in the Sixties, has epoxied glass over ply decks...)

* The moisture meter was interesting; it went off the scale over each deck beam. Alan thought this was due to the amount of metal in the vicinity, wit the old dumps and the newer bronze screws.
 
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IAN JACK

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thank you for reply, now i am torn between two decisions, do i leave her bare and put the hose over it now and then with a light scrub and chance a leak or three , or do i paint over that beautiful pine and have a tight deck and a good nights sleep in a dry bed.
Originally i was going to give the deck a soaking with half and half Linseed oil and turps but i am told that turns black so another good idea bites the dust.
The previous owner had just laid glass matting and stippled it with resin, no Epoxy, and within a year it had started cracking and moving,it just stripped off in sheets,luckily it hadn't harmed the wood.
 

Tranona

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The problem with laid decks like yours is that they were never intended to be long lasting, nor expected to be leak free. They were cheap to build and the working craft that used them kept them constantly soaked in seawater. This kept them reasonably tight and clean. However, it was quite common for them to only last 20 years or so before redecking was needed.

Such decks are less than ideal for leisure boats and there is no easy answer to how to deal with them. If the hull is tight, then epoxy glass sheathing and paint can work, but you run the risk of having a stiff deck and a floppy hull plus problems of keeping the join between them watertight. Polyester and glass is worse as described earlier - it just sit rigid on top of a flexible deck.

Coelan is potentially a good idea as it is very flexible and can cope with movements of both the substrate and the underlying structure. It is, however, expensive and difficult to apply effectively. As noted earlier it needs further finishing to be non slip.

Probably the best you can do is to make the seams as watertight as you can, deal with loose plugs if a screwed and plugged deck and make sure there are not places where stagnant fresh water can pool or get into joints. Do not put any oil or other goop on the bare wood as it only attracts dirt.
 

Kukri

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Deck leaks are annoying for the owner, on the few nights a year when she or he is aboard and it rains overnight, but they are deadly for the boat, because they allow fresh water below whenever it rains, and fresh water is the leading cause of death in old wooden boats...

The pleasure of owning a boat that never smells musty or "old boaty" when you first open the hatch, aboard which you can leave books, clothes, etc without a second thought, far outweighs the pleasure of looking at a bare deck.

YMMV
 

IAN JACK

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thank you for your excellent advice,i am making a list of yes and no's but no decision as yet. but a slight lean towards a good non skid paint is ahead. the wood is still in excellent condition and clean with no worn bits. oh well,decisions decisions.
 

Gordonmc

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I am somewhat surprised no one has mentioned the traditional method of sealing a deck, using stretched cotton canvas on a bed of paint.
Canvas will move with the wood unlike fibreglass which either part company or effectively seal in water.
Boatyards used to collect paint left over from other jobs for just this purpose.
 

Kukri

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I am somewhat surprised no one has mentioned the traditional method of sealing a deck, using stretched cotton canvas on a bed of paint.
Canvas will move with the wood unlike fibreglass which either part company or effectively seal in water.
Boatyards used to collect paint left over from other jobs for just this purpose.

Well, indeed I didn't mention it. There were two reasons for my not mentioning it.

I've canvassed three decks in my forty-three years of owning wooden boats. All successfully, but it is yesterday's technique.

A good canvassed deck was reckoned good for ten years, assuming nobody stuck a stiletto heel through it or dropped a marlinespike. A suitable deck for canvassing was made of T&G softwood, and the canvass was turned up inside beadings at the coachroof, cockpit and hatch coamings and turned down at the deck edge and buried under the rubbing strip. For success, the t&g has to be dead smooth, with no hills and hollows

Boatyards used to carry wide rolls of canvas for the purpose, to avoid or at least to minimize seams - this they no longer do. So you will need to have seams = a source of leaks and not pretty.

Canvas was replaced by Trakmark, a superior product which had a moulded PVC tread on the upper surface of the canvas and which did not need painting. It's no longer made.

Trakmark was in turn replaced by glass cloth in epoxy over plywood sheeting over the original deck.

In the case of the boat in question here she has a laid deck with covering boards and a rail; the laid deck will inevitably be somewhat uneven, and the beadings and rubbing strip would be an issue 0- unsightly and impractical. You would have to terminate the canvas at the inboard edge of the covering board, and cover the edge with a beading, which would not look nice at all,

The best approach here, with an old laid deck which is still securely held down, is Coelan. It works.

I won't say it is never right to use canvas; if you are restoring a small Hillyard or a Blackwater Sloop or similar that was originally built with canvassed decks and you are seeking a high level of authenticity, it may still be appropriate. But in general, the newer techniques are better.
 
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Gordonmc

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You are, of course, absolutely correct and I apologise if it seemed as though I was teaching egg-sucking.
My last boat was, indeed, a Hillyard. The original canvas decking was sound 40 years on.
 

Kukri

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You are, of course, absolutely correct and I apologise if it seemed as though I was teaching egg-sucking.
My last boat was, indeed, a Hillyard. The original canvas decking was sound 40 years on.

I believe we are "on the same page"! Congratulations on not dropping marlinespikes, anchors, etc! :)

Which way did the deck planks run? I was once told that it dawned on David Hillyard at some point, possibly in the hard chine 6 and 8 tonners' era, that if he ran the t&g deck planking at 45 degrees to the centreline he could use shorter lengths and avoid waste, so he proceeded to do so, but I don't recall having seen one.
 

burgundyben

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Deck leaks are annoying for the owner, on the few nights a year when she or he is aboard and it rains overnight, but they are deadly for the boat, because they allow fresh water below whenever it rains, and fresh water is the leading cause of death in old wooden boats...

When I joined YBW we had the old Classic boat forum, it was words of wisdom such as those that made me the wooden boat owner that I am today. Safety at sea first. Look after the timber second. Cosmetics if there's time.
 
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