Teak deck renewal

[SYJetzt]

My teak decking at the entrance to the cockpit looked brittle, so i renewed it.

1) Removal of the old plywood backed sheets with a hammer drill, using a chisel.
It took 15 minutes to rip the old teak off, including the plywood backing.
As expected the tool left some deeper scratches in the GRP surface.
2) Repairing the scratches with thickened epoxy and a layer of peel ply, after curing sanding with 60 grit, cleaning with acetone
3) Glueing the new teak strips (35x6mm) without plywood backing to the freshly sanded surface using sikaflex
4) Caulking  the seams with TDS  SIS 440
5) Overall sanding with 120 grit
 

[Lazy Pelican]

Nice job. My bathing platform needs doing in the near future. Unfortunately I won’t be able to take it home😥.

[Ailatan]

Nice job indeed!
Do you have a picture of how it was before? My deck has seen better moments and I don't know what to do.
Do you think I can use your technique to change the whole deck? How could I bend the wooden strips along the deck sides?

[symphony2]

It is impractical to replace the teak decks using glued on strips. Most people remove the teak completely, (a major undertaking - I think Yngmar has a thread on the subject) and then use an alternative non slip finish such as Kiwigrip. If you want a teak or teak type deck then the alternatives are to have panels made up like the originals or one of the "fake" teak looking products such as Tek Dek or Flexiteek. There are ither possibilities such as cork based finishes, but these are less common.

[SYJetzt]

It is impractical to replace the teak decks using glued on strips.

As you can see its not impractical. Yes, its much easier to do in a workshop instead of working on open deck, but it was a lot easier than i suspected before.
The bathing platform has been renewed by a professional last year in the same manner, and i watched the pro closely.
I expect that the remaining teak surfaces in the cockpit need replacement in the next 2 to 3 years, so i will start using the same procedure.

Do you have a picture of how it was before?

Sorry, i don't have a photo,but there was the teak cover down to less than 1 mm, and the caulking did not stick in places

Do you think I can use your technique to change the whole deck? How could I bend the wooden strips along the deck sides?

I expect its not possible to change teak areas made of bent strips without screwing the strips down when glueing. But i think its practical to replace the plywood backed panels  with straight strips like bavaria used them for the cockpit flooring and seating.

[symphony2]

You will have great difficulty in bending even 6mm thick strips of teak to get a swept deck, even if you screwed it down which in itself is a daft thing to do on a GRP deck. Your method works fine if you have straight strips - I did a whole deck, cockpit and coachroof on a 26' boat that way (never again!). The only practical method is pre-formed panels which are not a DIY job to make, but guess could be glued down DIY.

[Ailatan]

What do you think about this "teak" (I suspect it is not even teak) deck?
The black caulking is disappearing every time I clean it and the wood has grooves because the previous owner was a big fan of hard brushes because I found three of them when I bought the boat.

[geoff]

As long as the strips of teak are not lifting from the substrate , this looks to be an easy if tedious recaulking job. It an be done in reasonably small sections ,masked up to minimise mess then troweled flush. As long as there is still 3 or 4mm of teak left . Geoff

[symphony2]

Yes, that is what 20 year old plantation grown teak looks like, particularly if stiff bristle brushes have been used. Looks well stuck down and worth the effort to take out the old caulking and recaulk with TDS. Long slow horrible job but will probably give 5-10 years more life.

[tiger79]

What do you think about this "teak" (I suspect it is not even teak) deck?
The black caulking is disappearing every time I clean it and the wood has grooves because the previous owner was a big fan of hard brushes because I found three of them when I bought the boat.

It's very, very worn.  However, the effort involved in replacing it is huge, so could be worth trying to renovate it.  You need to sand the inside edges of all the caulking gaps, and you must mask both edges of the gaps before caulking.  It's essential to minimise the amount of caulking which gets on to the surface of the deck, as sanding it off will remove a lot of teak too.

Best to work in smallish areas at a time.  Keep some solvent and rags handy, as you will inadvertently tread on wet caulking at some point!  Keep a cardboard box on deck with a brick inside it, and drop each piece of masking tape in it as you remove it.  The brick is to stop the box blowing away (don't ask me how I know this!).

To sand the surface of the deck, I used the lightest DIY belt sander I could find, with fine grade belts.  Don't try to sand out all the furrows and cracks, as you'll end up with nothing left.  A little triangular detail sander is ideal for the awkward bits.

When you've finished, treat the deck with Boracol two or three times a year, this will keep it looking good with minimal maintenance.  And only ever use a sponge to wash it.

I renovated the teak deck on my old Hallberg-Rassy 352 about 20 years ago; my knees are still complaining!  So my last tip is to get some very good gel kneepads.

[Yngmar]

What do you think about this "teak" (I suspect it is not even teak) deck?
The black caulking is disappearing every time I clean it and the wood has grooves because the previous owner was a big fan of hard brushes because I found three of them when I bought the boat.

Lucky you! I wish our caulking had disappeared instead of turning to sticky goo.

There's not much teak left, but if you're not too picky you can stretch it on for another five years or more depending on use, location and how carefully you handle it.

Recaulking it all is a lot of wear on your spine and knees though, and then you still have to rip it all off in a couple years down the line. Not to mention a surprising amount of expensive deck caulking. So consider your options before you decide which way to go.

[Ailatan]

Thanks for all your advice. I think I will give it a second opportunity. I'll put it in the to do list for next winter

[geoff]

The usual caulk is very expensive , I  use geocel 201 a one part polysulphide  . I have used it for many years all over the boat and it shows no sign of degradation after time. The best thing about it is 1/3rd of the price for a bigger tube [380 ml verses 310 ml ] Geoff

[Joe]

Thanks for all your advice. I think I will give it a second opportunity. I'll put it in the to do list for next winter

Next winter is coming soon. Perhaps a good option would be black epoxy:

https://www.yacht.de/ratgeber/ratgeber-downloads/das-teakdeck-sanieren-mit-epoxid-127567

[symphony2]

It will be interesting to see how long that lasts. The big downsides with epoxy is that it does not like UV light and it is inflexible so does not allow for movement of the wood. It is OK with thin laminates - I used it to grout  the teak strips in a cockpit more than 30 years ago, but the strips were straight and only 2.5mm thick, plus the cockpit on that boat was always covered when not in use. I would not use it on curved strips on a deck unless they were worn thin such that conventional caulking would not hold against the sides of the seams.

[Ailatan]

Thanks for all your inputs.
Geoff, I think that Geocel 201 can only be found in UK. I have found other products in the EU but they are different. Even Sika has one product with the same component but it is different. In any case, do you have experience of this product hit by the Mediterranean sun for more than 5 years?
Joe, I agree with Symphony that epoxy+sun is not a good combination but can be an option if the seams are too shallow to hold the caulking

[PEA-JAY]

I find the information in this topic very interesting especially as PEA JAY’s eighteenth relentlessly hot  Mediterranean summer is fast approaching! Considering I have never oiled the cockpit teak and I use a power washer to clean it, I seem to be fortunate I haven’t destroyed it over the years. The caulking is still all there but it’s hardened considerably and I can now see how worn down the teak is. In a few years time I’ll need to do something about it. I have been mulling a possible solution of sanding off the teak layer without disturbing the ply base and gluing a fresh layer of teak or one of the very real looking artificial products. I’m curious to know if anyone has opted for this solution instead of starting by tearing out the ply base? .

[geoff]

I think that polysulphide sealant will be available everywhere in EU . It is a commonly used high grade building product and will be formulated to withstand local conditions. It is now over 10 years since I owned a boat in the med [a beneteau 411] but I have no idea where it is now. Geoff

[Ailatan]

Well, the winter has come and this project is on.

I started sanding the wood to get good adhesion for the masking tape but some parts are very damaged so I don't want to sand to get a completely smooth surface because then almost all my teak will disappear.
As this project is physically quite demanding I am alternating the sanding with removing the caulking from the joints. Fortunately most of the caulking has disappeared but not between the deck and the cabin and the deck and the gunwale and that job has to be made by hand as I am scared that any tool can damage the gel coat.
Now the questions:
Does anyone know of any teak filler that I can use where the teak is very damaged?
When the teak join the gunwhale, do I need to put masking tape in the vertical part to protect the gel coat or just on the teak?
Finally I am considering using the Geocel or similar product as I was trying to reach the customer service of TDK but they don't answer my questions, and I don't want to give my money to companies that don't listen to their clients, but I have seen that they have changed the formula and I am not very sure that it is polysulphide any more. Has anyone tried this product recently? Do you think it can work?

[Ailatan]

I keep on working on this project and I have started with the foredeck. I have realized that Bavaria used two different sealants: the sealant used in the seams has desapeared in most of them but, in those places where still remains, it has turned into dust or it is very deteriorated; then there is a second sealant to fill the gap between the panels of teak and the toe rail on one side or the cabin on the other side. This second sealant is in very good shape and it's very difficult to remove.

Is anyone familiar with the method used by Bavaria to build and glue this panels of teak that can tell me which sealants were used?

On the other hand, I haven't decided which sealant should I use to re caulk the deck, but I've found this interesting article (https://www.practical-sailor.com/boat-maintenance/paints/teak-deck-caulks-rated-for-durability-and-resistance-to-chemicals)
 and I would like to share it with you. It was written a few years ago but the brands are still in the market and, as far as I know, there is no improvement in the chemicals base of the sealants.

[tiger79]

Is anyone familiar with the method used by Bavaria to build and glue this panels of teak that can tell me which sealants were used?

The teak deck was made off-site in panels.  In the Bavaria factory, the panels would have been glued to the deck and the joins and edges caulked. 

The panels were probably made by Wolz Nautic, who use both PU and MS polymer caulking.

Bavaria would most probably have used Sikaflex to caulk the joints (and to glue the panels to the deck).

[Ailatan]

Thanks Tiger79, to the best of my knowledge, the MS polymers caulking are much more UV resistant than PU sealants so probably Wolz Nautic used a PU caulking for the seams.

Do you know what Sika used Bavaria or the chemical base of the caulking? Because there is a huge difference in terms of quality.

[tiger79]

Thanks Tiger79, to the best of my knowledge, the MS polymers caulking are much more UV resistant than PU sealants so probably Wolz Nautic used a PU caulking for the seams.

Do you know what Sika used Bavaria or the chemical base of the caulking? Because there is a huge difference in terms of quality.

I'd have hoped they'd have used 290DC PRO, or whatever the equivalent was then.  This is a PU product.

[Ailatan]

I'm still working on this project and I do not expect to finish before summer.
While in the process of sanding the deck I also sanded the teak toe rail that was very deteriorated and the result is very good, so I was wondering if there is any product to keep the teak colour instead the grey one. I mean something easy to keep not varnish or something similar

[Yngmar]

You can oil it: https://www.woodworkingtrade.com/linseed-oil-vs-teak-oil/

Won't last as long as varnish, but easier to re-apply and good for the toe-rail as it will inevitably see some abrasion that would cause varnish coatings to be punctured and stain beneath.