Re-caulking a teak deck..?

[PaulBrun]

I would appreciate anyone giving me advice on, or directing me to another thread on the topic of, re-caulking a teak deck. I have a number of areas, mostly on the sidedeck, where the caulking (sikaflex) is standing proud, or even separating completely from the groove between the teak planks. The wood is mostly still OK, and I really do not want to strip the deck right back, at this time. But I would like to repair the areas where the caulking is not good, and cure a few slight leaks. There are also some screwheads showing, and these may also be a possible point of ingress, so these will need to be removed, re-drilled, and re-plugged at the same time. The cost of repairing, or renovating, the deck is obviously going to be much less than replacing it altogether, but I want to be sure I do it correctly, and that I am not wasting my money..? All advice will be much appreciated. PS. The bowsprit that I replaced last year came out beautifully, and compliments the deck perfectly..!

[Bob Cleek]

Do the search feature. There's lots of discussions on this often misunderstood topic.

First, the threshold question is whether it is a true laid teak deck, or just a plywood deck with teak facing on top. That's going to make a big difference.

As said often before, on a true laid deck, it isn't really the goop you put on top of the caulking that stops leaks, it's the cotton driven into the seam. The goop just protects the cotton.

On a teak faced deck, you have a tougher problem because you have to figure out how the leak is happening. It can come in anywhere and end up dripping down on your bunk every time!

Before you "drill down" to reset fastenings and bungs, determine just how thick that teak really is. On a faced teak deck, when there's no longer enough depth for a bung to "stick," it's usually because the teak has worn down to the point where replacement ought to be considered because there won't be enough thickness to allow both the bung and the screw to hold. On a laid deck, you might get away with squeezing another quarter or 3/8 inch out of it, maybe.

Sikaflex will dry out, harden and crack in deck seams every time. You can dig a bit out and slap a bit more on top of the spot if you want. It may work for a while, or it may not. It probably won't stop the leaks for long, or at all.

[PaulBrun]

Thanks, Bob, for your helpful, and enlightening advice. I was not aware that Sikaflex (or as you call it 'Goop') is liable to dry out and crack..? I thought it was meant to remain semi-pliable, so that it would seal the gaps between two pieces of timber that are apt to move, shrink, swell etc..? Anyway, it does appear to be the case, as some of it has become rather stiff, and has cracked, particularly where it is in full sunlight all the time. The deck is, I believe, laid onto the original wooden cross-members, although they may well have 'glassed over' them first, before laying the teak..? I don't think there is any plywood underneath, though it's difficult to tell. There is certainly no evidence of any cotton, just the 'goop'. The teak strips are rather thinner towards the edge of the deck, where all the 'traffic' is, but I am hoping that there is still enough 'meat' there to re-screw them down..? There is still more than 10 mm in most places. I think it was originally 12 mm, or even thicker originally. If I can stop some of the leaks, for a while, I will be happy. But ultimately it looks like I will have to re-new the deck completely, at some point in the future..? Thanks again.

[BBSebens]

My Father-in-law and I recently finished re-doing the teak deck on our Cheoy Lee Offshore 31, which is a glass boat. It has a Teak deck, with fiberglass over that, with the teak strip decking on top of that. wierd yes.. but its an odd duck. Our deck was in similar condition to yours it sounds like, and we didnt want to tear it off either. some of the strips were fairly weathered, but we decided to leave them all. we hogged out all of the caulking with a Fein Multi-Master. There is a specific attachment for them that is purpose made. Very handy. then cleaned up the grooves with a Dremel to get them clean. We replaced all of the screws (980 of them) and re-plugged. We gooped it all up and sanded it down. this worked out pretty good, because we got the deck down to flat, got rid of the excess goop, and didnt have to tape every single piece of teak! It worked out really well. I cant recall the goop we used, but it was made in such a way that it would stick to itself and seal even if it had allready dried in that spot, great for going back and fixing voids. When I find out what we used Ill put it up here.

This while process took about 5 months of evenings and weekends, and the end result is pretty darn good.

Can't wait to use it.

[PaulBrun]

Thanks BB, for your feedback. The work on my deck is going on at the moment, but unfortunately, I am not there to supervise, or to observe how it's going..? The guy doing it is a local craftsman, who assures me that it should be no problem to repair the deck, and cure most of the leaks. But he wouldn't guarantee it..! The 'goop' has all been dug out anyway, and some of the screws removed. New 'goop' was inserted into the channels, and the screws redrilled, and replugged. They are using a Sikaflex product, which comes well recommended. I forget the product code number, but it is specifically for teak decks. They are now busy sanding it all down, and should finish by the end of this week. The proof as to how well it has been done, will be after the first heavy rainfall, due soon with the onset of the monsoon season..! I will post again after that, with some pictures. (hopefully, not of myself lying in my bunk, holding an umbrella..!)

[tjaldur]

I believe that the process of caulking is not quite what is done on a teak-deck, placed on top of a glassfibredeck. Although it may of course be that my understanding of English is not adequate.

When I do caulking, my deck is a wooden deck where the boards are 50 mm thick and they are shaped in a narrow "V"-form so that the opening in the bottom is 1 mm or less and the opening at the top is 4 - 6 mm.

First I need to use a hammer to squeeze hemp between the boards. This is done three times hammering irons with different widths (from 0mm to 4mm) on the irons I am using. Before that I must remove the old caulking with a particular tool. Fortunately one can now buy a "Fein Multimaster" that has particular knives for removing the old caulking.

After the hemp is hammered into the channels I squeeze in Sicaflex nr 291. Originally it was tar that was used. But tar tends to melt and expand in the summer-heat and leave residue on the feat/shoes. Also tar needs to be heated while working it, with fire as a result from time to time. Anyway it is correct as has been said above. It is the hemp (or the cotton) that prevents the leak, because it expands when it gets wet. The goof, what ever it is, is only there for preventing the hemp from leaving the channel.

It is hard work. My "caulking speed" is about 1 m/h. Also I need to have dry weather for a week so that the boards are thoroughly dry and the openings maximum wide when doing the caulking.

[PaulBrun]

You are absolutely right, TJ. I have mis-named the thread, because I am not really re-caulking the deck at all. I am just re-sealing it, I suppose..? But thanks for the very detailed and useful description of what would be involved, if I was doing it in the traditional way. Maybe I'll do that, when it comes time to replace the teak deck altogether..? The shape of the teak strips is not V-cut, but there is a rebate into which you squeeze the 'goop'. On my deck, the rebate has pretty much worn away, in a few places, which means that the repair job there might not be as successful as I had hoped. But in most places there is enough wood remaining, and the rebate should be able to accept the new sealant. The hull of the boat is solid wood, and is definitely caulked, as I found some when repairing some minor damage. But they then coated the entire hull with an epoxy 'sheath', on the outside only, which makes for a very clean finish. The deck is also wooden planking, beneath the teak decking, but I think it was also sealed with fibreglass, as there is evidence that this is the case along the edges. The screws will have punctured this, and be the obvious source of entry for the water that gets in. The exposed screwheads need to be replugged to stop this, hopefully..? As I said before, I should find out how good the repair job is in the next week, or so, as the forecast is for rain, and thunderstorms..!

[tjaldur]

If it is the case that the opening is sort of squared "U"-form, then, with fear of stating the obvious, it is very important that the sides are absolute clean and primed with a primer so that the sica fastens properly to the sides. Also that you use a non-adhesive tape in the bottom so that the sica does not fasten to the bottom, but only to the sides. A trick of the trade is to use tape on both sides of the top of the board so that you do not get sica on the board when you force the sica into the channels . After the sica has hardened, you just remove the tapes and the boards are clean.

Covering wood with epoxy may be dangerous. Then it is very important that the wood is properly aired on the inside. Particularly not covered with painting or any other sealant.

[Lew Barrett]

Check out "Teak Deck Systems" or "TDS" products. They are considered the premium product for this application by many.

http://www.teakdecking.com/caulking%20products.htm

[PaulBrun]

Thanks again TJ, for your sound advice and sensible observations. I am pretty sure that this is the method he is using on my deck..? As well as the sikaflex 'sausages', he asked me to purchase a number of rolls of paper masking tape, and a gallon of primer. I had someone go down to take a look at his work, and they say he appears to be doing an excellent job. But the proof is in the end result, being both waterproof, and long-lasting..! I also agree 100% that coating a wooden boat with epoxy is dangerous, but this was how I bought it, and there seems to be very little evidence of any problems, at the moment. However, the inside of the boat was also painted, and in one place I did find some softening of the surface of the wood. To remove all the paint would be a huge task, so for now I am just keeping the boat well-aired, and a close eye on things. I do plan to re-fit the interior one day, so at that time it might be a good idea to strip it back to bare wood..? We'll see. I have contacted TDS, Lew, and requested more information about their product line. If and when I do re-new the whole deck, I will try to find a local source, or order directly from the factory. Again, thanks for your help.

[tjaldur]

An easy and inexpensive way to remove old paint is to cover the paint with the ancient brown/green soap (the one that your grandmother probably used to wash the floor) then cover the soap with ultrathin plastic film (the one modern wives use to cover food in the frigidaire), preventing the soap from drying and making it do its work. Then after a couple of days, remove the soap and the paint with a scraper. If needed repeat. No dust and no (petro)chemicals that we really do not know what are.

[Andrew Craig-Bennett]

I must say that I had quite good results with Sikaflex - it needs to be the "DC 290" grade, not the ordinary stuff, and you must use the right primer.

But in the end I painted my solid teak deck with Coelan. Not a drip in the last 12 years.

[PaulBrun]

Thanks again, TJ. I will try the trick with the soap, to help remove the paint on the inside of my boat's hull. Is it carbolic soap you're talking about..? I suppose that would have a chemical effect on certain types of paint, just as it had on the stubborn stains in my grandmother's day..!

And thanks Andrew, for confirming to me that I am using the correct Sikaflex products. I am curious to know what 'Coelan' is, so will try a 'search' for that..? I was also curious to know where your 'location' is..?
I guessed at Maldon, and wasn't too far out. I was born in that area, and briefly enjoyed sailing traditional boats on the Blackwater, some years later. But I think I prefer my present location..!

[Boatsmith]

sika flex does not sell deck calking in the us we have removed sikaflex calk froma dozen new boats because the sika stayed too soft and when hot would actually track around these were on imported boats ie viking sport cruisers and riviera sport fish boats we use eithr teak decking systems or maritime wood products calk tds regards david

[Lew Barrett]

One can give good advice based on experience but it is frequently overlooked, Boatsmith. Jay Greer also has much to say on the topic.

[tjaldur]

PaulBrun:

I do not know what carbolic soap might be. I am referring to soap in its purest and most original form. The idea is to attach the painting, not the wood. The soap is only fat and some base that I do not know the name of in English. No extra additives that may damage the wood.

[Capt. Mike]

I have a lot of decks to maintain on my boat I had to reseal most of them. but I keep my boat in a covered slip or I could not get this boat finished.

www.bigwoodenboat.com

http://web.mac.com/tanyard/Site_6/teak_decks.html

[PaulBrun]

Thanks everyone for your good advice, and sound opinions. I have gone with the Sikaflex because that was readily available, and recommended by most other people in the area where I keep my boat. I have not yet seen the end result, but I am told that it looks OK..? The proof will be, as I said before, in whether or not the deck still allows water to come in, or if it has made matters worse..! This is only a 'temporary' repair, which I hope will last a couple of years, until I can arrange to do the job properly, and completely.

[svjester]

Has anyone ever used TDS for "caulking" an old hard wood floor? I pulled up these old lead covered floor planks and am "flipping" them and then refinishing them. What I'm wondering is if I can use TDS (or maybe Sikaflex) to caulk in between the still prominent gaps? I know it's off topic but I'd welcome any comments...