There is nothing that can make or break the look of a sailboat more than the look of the exterior teak. But teak isn’t a maintenance-free boat surface that can be ignored or neglected for a long time. Though teak doesn’t rot, it can crook, check or look dull if proper care is not provided. Keep in mind that this article is not about deck restoration, so, we will not going to get into applying new Sikaflex on your deck, etc. 

Teak is amazingly flexible and can be made new again even after a lot of rough use. Teak with grey weathering rarely extends far below the surface of the wood. Instead of tedious sanding and scrapping to restore the weathered surface, a standard chemical cleaning is enough to bring back the teak from its worst condition to nearly its original appearance. Chemical cleaners can clean almost the worst off weathered teak.

Though, chemical cleaning may be tough on wood. Many chemical cleaners depend upon an acid or a caustic to bleach and clean the wood’s surface. But sometimes these chemical cleaners wear away the surface gradually. To achieve the best results, you should never allow your teak to get to that condition where you have to take these drastic measures. However, if things happened and there is a need for extreme cleaning, make an effort to keep it clean moving forward. 

Keep in mind that this article we will not going to get into applying new Sikaflex on your deck, etc. The article is coming though and will link it here as soon as it’s available.

Cleaning

If the teak of your boat got dark brown because of age or got weathered grey due to negligence, then the first thing necessary is to clean it thoroughly. The severity of the discoloration of your teak will tell the restoration method required. Since cleaners contain caustic and acids that are tough on wood, you have to use a mild cleaner as less as possible to do the job. The value of a mild scrub using a soft cleaner is that it’s gentle for the teak. As it is more probable to have soft cleaners in your boat, always try this method before applying drastic measures. 

The mildest cleaner for teak could be a common purpose domestic powdered soap. A concentrated powdered cleaner with vigorous scrubbing using a soft brush will clean the teak, which is just dirty. Scrub it as lightly as you can and also keep in mind that you have to scrub across the grain. Every time the teak is scrubbed, softer wood is removed, which eventually causes a rough surface that elevates the grain. Using a scrubbing brush regularly to scrub the grain, makes it weak and rough.

First of all, try to wet down the teak with fresh water, then clean it with a detergent solution. After that rinse it with water, then leave it to get dry for some time. If the teak’s wood gets clean, even a light tan, then you are in luck. Otherwise, you will need to use a powerful cleaner. 

Pro-Tip: You can also use the same washing machine power that you use to clean your clothes. I am talking about the powered detergents with the small grains in them. Those will actually help scrub the wood better because the granules will get into the teak. The best way is to sprinkle it directly on the teak instead of using a bucket and then doing it. However, you are looking for better results the following options could be better for you.

One-Part Cleaners

The next step is to use “one-part cleaners” made explicitly for teak. It can be liquid or powdered. Most cleaners consist of a mild and abrasive acid-like oxalic acid or phosphoric acid. These acids are more efficient in lightening the surface of the wood than a simple detergent. Most of the household cleaners have oxalic acid. You should take precautions while using these cleaners, which contain acids. 

Even a badly weathered wood of teak can be cleaned using “one-part cleaners”. After drying the wood, it should come out as light tan. After cleaning one time, if some areas remain grey, repeat cleaning will do the trick. Still, if the wood of the teak is discolored or mottled, then you have to use “Two-part cleaners”.

I recommend this teak wood cleaner from Star Bright, it is soft on the teak but gets the job done. Make sure to get a Scrub Pad and a Stainless Teak Scrub too so you can get the best result as easy as possible. Here is a video on how to do it properly:

Two-Part Cleaners

These cleaners are more powerful, but they are hard on the teak. They are potent acids and caustics that can do a fantastic job of brightening and cleaning the teak. But it should be handled with care to avoid harm to adjoining surfaces. Also, surrounding surfaces, whether varnish or paint, should not be tainted by these cleaners. Continuous flushing of surrounding surfaces with fresh water among cleaning is usually sufficient, but covering off freshly varnished or painted surfaces will be more efficient.

There are slight differences in the guidelines for different “Two-part cleaners”, but the common principles are described below:

  • Wet down the teak
  • Apply “one-part cleaner”, dispersing and gently scrubbing with a soft brush
  • When the surface of the teak is a muddy brown, uniform wet, apply “Two-part cleaner”, dispersing with clean stiffed brush
  • Apply and disperse the acid required to turn teak into a uniform tan
  • Wash it off thoroughly and then let it dry completely

Most commonly, the “two-part cleaner” is used twice as the first to obtain a uniform bright color. So it would be an excellent idea to buy an extra bottle of acid in case it’s needed. Also do not wash off the brown muddy surface of teak, unless the directives require it, after treating it with caustic. Furthermore, neutralizing the acid will reduce the problems.

This is the best 2-Part Cleaner made from TotalBoat and below is a video on how to use it. For large surface areas you might also want to get a get a large deck brash with a handle just to make the job easier.

Preparing for Finishing

A recently cleaned teak is a pleasure to witness, but the teak won’t remain fresh, light, and clean for a long time if proper finish is not applied. The teak’s surface will start to oxidize as soon as it dries. The earlier you complete the treatment after scrubbing, the better. 

Teak consists of grain that differs in stiffness, even in the same portion of the wood. Cleaning it with detergent may erode the softer parts of the teak’s grain, leaving ranges of firmer grain. The abnormality of such surface merely increases the speed at which the teak goes dull again.

If the surface of the teak that you have cleaned is plywood, there is a good chance that thorough polishing the teak, the surface may go right off from side to side, exposing the coating of the veneer, effectively ruining the piece. On the usual fiberglass boat, plywood or veneered components are the companionway hatch tops, drop boards, and occasionally cockpit soles and seats. Before polishing any part, inspect them cautiously to understand whether they are veneer or solid lumber. 

Polish the uneven grain of severely weathered teak once it is clean.

Decks are typically solid lumber, so they can create problems. If the flooring is less than half inch dense, and has beavered fastenings, polishing the grain edges will sand away sufficient solid to sand from side to side or release the bungs, revealing the fastenings. Even if the grain of teak is on fixed teak surfaces, you will be better off living with a clean uneven surface instead of opening the “Pandora’s Box” trying to make a perfectly flat surface.

On other hard teak objects such as toerails, dorade boxes, and handrails, thorough scraping of the washed surface, before applying it with sealer may produce an attractive surface. Don’t attempt to refurbish grey teak and badly weathered teak by scraping before cleaning it as I described above. There is a chance that you may quickly learn that discouraging quantity of scraping is necessary, and you will use chemical cleaners. Polishing both before and after the treatment is just a waste of effort, and may eradicate more wood. Teak with noticeable surface abnormalities would definitely take an eternity to scrap out to obtain an even surface. While cleaning with chemicals will swiftly lighten up even the inmost grain or gouges defects. Also, wait till the scrubbed teak is completely dry before polishing or applying teak covering.

Polishing scrubbed teak isn’t always needed. Mainly polishing is necessary if the teak’s surface needs to be preserved with oil covering instead of using a gloss polish like varnish. Granted, flawlessly smooth teak’s surface is more uniform in color. From a merely practical point of view, irregularities are insignificant except in the case of simplified scrubbing. Unless you plan to put the effort needed to preserve your teak’s surface between main cleanings, polishing the teak’s surface smooth is just a waste of your time. The chemical cleaning may recur the grain of the teak raising cycle, needing another rubbing.

If you are keen to keep your teak up, a good scraping will improve the wood’s form. The safest instrument for general smoothing is the high-speed sander like the “Makita XOB01Z” or any other small sander. I just like this one because it’s cordless, portable, and durable. It is also made by Makita, and I have great experiences with the brand. Inexpensive, slow-speed, and heavy sanders must be sidestepped. They leave revealing twirl marks on the teak’s surface that are emphasized by the finish. Also never use the sander on the surface of the teak to be scrapped bright.

The same is the case for a belt sander. A belt sander is maybe the most effective tool for leveling flat and large surfaces. But can also do some painful and permanent damage if the person using this tool is inexperienced. For hatches and decks of hard lumber, belt sander may be the solution, only if you’re comprehensively experienced with this equipment.

When doing power sanding, remember to cover surrounding areas of gelcoat. Just lightly touching the refined gelcoat surface with the sander will damage it. This same instruction applies to manual sanding. Remove the masking tape instantly after the completion of sanding. Even just leaving tape overnight on the exterior surface may make it difficult for you to remove. 

The adhesive residue could be removed with the mild solvent like alcohol and gentle rubbing with a rough cloth. Many teak coverings are easily put with polyfoam brush.

Remove dirt from the surface with a vacuum cleaner, after sanding. If electricity isn’t available, just sweep thoroughly with a large paintbrush or dusting brush. Obviously, you do not need to sacrifice your finest paintbrush. The cheapest stiffen brush will do just fine.

Applying Finish

The last step in restoring the surface of teak is the application of a sealer or coating to preserve for a long time the look of freshly installed wood. Your preference should be a covering that doesn’t blacken the wood. A good idea would be to look nearby boats whose teak looks good to you, then ask the owners about the products which they use.

No teak polish lasts for very long. To get the best results, monthly use of coating is needed, with good cleaning before putting on a fresh coat. You’re kidding yourself if you think a once-a-year treatment will keep your teak looking good. Don’t try to use domestic type equipment oils for teak. They may not stand against the weather.

Whatever teak covering you utilize, be wary of smearing it. Splattered teak covering will not look good when it’s put on fiberglass. However, it unavoidably blackens with time, leaving marks that look as ugly as varnish marks, and are hard to eradicate. Clean up these spills and overruns straightaway with any rag dunked in spirits like alcohol unless the manufacturer indicates an alternative solvent. Covering tape isn’t particularly efficient in defending surfaces from teak oil or varnish, as the thickness of most coverings is so thin that they just drain under the edge of the tape. The solution to this problem is careful use and thorough cleaning.

Depending on the look that you want to give to your boat’s teak you can get some standard teak oil from Star Bright for a matte look or if you want to go for a high-gloss varnish you can get this product made from TotalBoat.

Also, to avoid splatter and oil marks on the teak, the best way to apply the finish is with a foam brush. They are cheap and give the best result with lowest effort.

Maintaining

Your work is not done when the final coat of finish is applied. Teak requires constant attention to make it look good at all times. When a boat is used in saltwater, repeated wash downs with freshwater will definitely extend the lifespan of the covering. But, constant interaction with saltwater will likely decrease it. Highly traffic places like the teak cockpit will need the most care of all. Although they are easy to brush and retreat, sanding isn’t always desirable.

How to Restore Teak on a Boat – Conclusion

I know it seems like a lot of work. That clarifies why the exterior teak surface on many boats looks so dirty. It takes less effort than preserving a varnished teak surface. If you think you need varnished teak, first of all, try to maintain a freshly oiled surface just for a year and revisit the idea then.

Few things look better on a boat, mostly a white fiberglass sailboat than a well preserved exterior teak. A person who neglects teak wood may also be the same person who hardly replaces engine oil, and who hardly troubles himself to place the sail protections after a sail when he assumes he is going to sail again tomorrow. So, if you are looking for a sailboat to buy, remember that a clean and neat exterior probably means a well-maintained boat overall.