How to Clean a Sailboat Sail – The Right Way

There are some tedious activities that I put off for a long time due to the sheer anticipation of how much time and energy it will take, and cleaning my sailboat sails is definitely one of them. However, once I finally hunkered down and got to work on them, the process was actually pretty straightforward and easy. Luckily, I also found some excellent resources to ensure I was cleaning and handling my sails properly.

So, how do you clean a sailboat sail, the right way? As it turns out, there are a numerous simple and natural solutions for cleaning a sailboat’s sails, and the method will depend on the type of material the sail is made from, and what type of dirt or damage that needs to be removed.

Additionally, I discovered some crucial how not to’s that you will most certainly want to know about so that you don’t accidentally damage or destroy your expensive sailboat sails. 

Reasons You Might Want or Need to Clean Your Sails

Firstly, you might be wondering when one is supposed to clean one’s sailboat sails and how regularly. Unlike how a car needs to be serviced roughly every 5,000 miles or so, a sailboat sail only needs to be thoroughly cleaned when its owner notices a certain types of grime, wear, or a nasty nest of spiders (true story.)

Here are some tell-tale signs it is time to lower your sails and scrub-a-dub-dub.

  • You Spot Mildew: You will start to notice spots of grey at first, until the mildew grows black, usually in the same recurring place on your sails (often at the bottom near the folded creases of the sails.
  • You Spot Lots of Bird Droppings: While some may consider bird droppings to be good luck, I, along with many health advocates, believe it to be quite unsanitary. You’ll want to remove any pelican feces, if not for the appearance, for your health.
  • There’s Obvious Dirt, Grime or Grease: I once cruised on a friend’s vessel whose sails were so filthy that they were no longer pearly white, but rather brownish-yellow. It was pretty disgusting, honestly, and a brown sail is more than enough of a sign to know to lower the line and give that sail a deep clean.
  • Your Sails Have Been In a Dark Dusty Corner Somewhere: While I would not recommend abandoning your sails in the dark, dusty corners of your storage unit (spiders nests, remember?), I am aware that this kind of thing does happen. However, while you do conveniently have your sails in storage (or grandma’s attic), you may as well give them a good hosing down before you hoist them up on your boat. 
  • You Had a Particularly Messy Sailing Excursion: If you go out for a cruise and any of the following happens, you may consider giving your sail a thorough rub down when you dock back into port.
    • Maybe it was a particularly rough sea, and you know your sails took a good beating, and there’s way too much salt residue clinging to them.
    • Your new sailing companion forgot to mention their tendency toward sea-sickness, and they christen your sails with their recent clam chowder.
    • Your relaxing wine and cheese cruise was a little too relaxing, leading your brother-in-law to stumble and fall, his full cup of wine soaring to the heavens above him, landing serendipitously upon your crisp, clean sails. (It’s happened.)
    • There’s a fight on your sailboat after a little too much wine (there’s that wine again), and your best mate has a better right hook than you expected, and your inebriated senses make you dodge and duck just a hair too slowly and your freshly broken nose creates a beautiful spray of blood across your perfectly pearly sails. (Hey, who am I to judge what happens aboard your private vessel, as long as you have a first aid kit handy…)

The Wrong Ways to Clean a Sailboat Sail

Before we go through the in-depth list of how to properly clean your sails, it is prudent we investigate the wrong ways to clean them as well, so that you can avoid any easy-to-make mistakes.

Here are some questions many sailors, including myself, have initially pondered when gearing up to wash their sails, and the reasons why these methods are unfortunately ill-advised.

Can you Bleach Sails?

A lot of folks want to know whether or not one can use bleach, oxi-clean, or acetone to clean sails. I do not recommend it for specific sail fabrics. While you ‘technically’ can use any of these chemicals, it could come at a cost to your sails. If you can successfully clean your sails without using these very harsh chemicals, I would urge you to do so.

When it comes to mildew, I understand the desire to use bleach. It’s what I use as soon as I notice any of those pesky grey spots sneaking along the edges of my glass shower sliding-door. Thus, I empathize in wanted to sufficiently douse your moldy sail in bleach. However, many sails will be heavily damaged by bleach, and it could even weaken the strength of your sail up to 60%. That certainly does not seem worth it, does it?

If you just can’t fathom getting rid of mold or mildew any other way, then at the very most, you may create a dilution of water with the faintest amount of bleach to clean your sails, but at your own risk of ruining or weakened their fragile fibers. (This may be possible when cleaning Dacron sails, but not when cleaning Nylon or Kevlar sails – they are much too fragile for bleach.)

Can You Put Your Sails in a Washing Machine?

No. This is a poor idea since there is no give or stretch in the type of cloth used to make sails, and the washing machine (depending on the kind you have) may twist and pull at the fibers until they are weakened. And that is assuming the washing machine doesn’t put a tear in the sail entirely, which has happened to me with two different pairs of normal bed sheets. If a washer can easily shred bed sheets, trust that it can shred your expensive sails.

Also, suffice it to say that while you would never want to use a washing machine, you most certainly do not want to use a machine dryer. The intense heat will severely damage the resin in your sails, and when you pull it out, it will likely be crinkled up and misshapen and will be extremely hard to re-shape after that point.

Can I Soak My Sail in a Chlorinated Pool?

Due to the massive size of a pool matching up with the massive size of your sails, it makes sense you might want to just chuck your grungy sails in your chemical pool. In some instances, this might be okay, depending on the fabric of your sails (Dacron, for example). However, much like bleach and oxi-clean, chlorine is a tough chemical. Granted, our bodies can swim in it without our skin withering away – so it’s not as harsh as bleach. However, I still feel confident there are other safer ways of cleaning your sail that hopefully disables any weakening of its fragile material.

However, if you have a Dacron sail and you want to put it in your chlorinated pool for a short period of time, I don’t think it will permanently damage your sail.

To Recondition and Re-Resinate or Not to? That is the Question.

There are some really top-notch professional companies that have perfected chemical engineered cleaning processes to clean sailboat sails. Based off of customer reviews, it also seems that many people have a lot of success with this method.

One company, in particular, located in Pennsylvania, created a cleaning process they call the LaMauney Process. This entails the cleaning of polyester/Dacron fabric sails, followed by a replacement and fortification of the resin in the sail fibres. They do this to strengthen the sail – and they also add some cool features like UV protection and anti-fungal elements. 

To learn more about this process, watch this video of Jerry Fultz from Sail Care, Inc.

This may or may not be a great option for cleaning sails; therefore, the jury is split on this one. Some companies are adamant that reconditioning and re-resinating sails does not work and is a bad idea. They argue that if a sail is old, the new resin will wear away after only a few sailing seasons and that the heat involved in this kind of cleaning and refurbishing process can shrink boltropes and leach lines, making the problem worse (rather than better). The biggest argument being that if your sail is so distorted or messed up, the cost of a new sail is going to be a much better value than sending our sail out to be professionally cleaned and re-resinated.

The Right Ways to Clean a Sailboat Sail 

Now that you’re well versed in the chemicals and methods that are NOT recommended for the cleaning of your sails, let’s get straight to the best ways to clean your sails (based on mess/problem and the sail fabric). Firstly, make sure you have a space cleaned and prepared that is large enough for your sail. This is your first obstacle. Everything after that is relatively easy.

Allan Stokell of Grampian Marine YouTube Channel also has some excellent cleaning tips and has years and years of experience as well. (His story about how he dries his sail after he washes it is worth listening to.)

Cleaning Based on the Type of Problem

  • Dirt, Thick Salt Residue, or Bird Feces – This standard type of grime, which will eventually be found on most sails, can be easily cleaned with a mild detergent or dish soap and a gentle brush (one with soft bristles). You’ll then follow this with a thorough rinse of fresh water and lay the sail out on a surface (preferably one that allows both sides to dry.)
  • Oil or Grease Stains – Also removable with soap and warm water. For difficult stains, you can add the tiniest (like a quarter size) of bleach. But again, I must warn you the risk you take in using bleach (especially on nylon and Kevlar sails.) Vinegar can also be used to lift some grease stains (I use a solution of normal dish soap, water, and a little bit of apple cider vinegar to clean the grease and grime off my stovetop and it works serious wonders.) However, there is a caveat. Vinegar can eat through certain materials – make sure your sail can withstand a strong vinegar before you go dousing it. For oil and grease stains, a normal, soft bristled scrub brush will suffice. Rinse with fresh water, lay out to dry.
  • Rust & Metal Type Stains – Despite its potential to damage your sail, acetone is excellent at removing this specific type of metallic stain. However, for our purposes, we recommend using a dish soap with water with only a trace amount of acetone (again, baring if you have a nylon or kevlar sail). In this instance, that were are trying to avoid harsh chemicals, you may try SimpleGreen. And if that doesn’t do it, try a white rust stain remover.
  • Mold and Mildew – As soon as you spot mildew, you’ll want to instantly isolate the area so that the mold does not continue to spread to the rest of the sail. If you’ve got a Dacron sail or another durable type of sail material, you may use a 1% or less bleach solution (or an extremely watered-down store-bought solution). In the same vein, vinegars are also known to kill fungi and bacteria – but you’d want to use a similar caution when using vinegar on your sails, as you would with bleach. Thus, our third recommendation is Lysol. Lysol is a great anti-fungal spray, and kills spores, and prevent their continued growth. You can spray your mildew with Lysol and wipe away several hours later, and the mold should be gone.
  • Blood or Wine – I know the above scenario seemed outlandish; however, it would not be the craziest thing in the world to somehow have blood or deep red wine stains appear on your sails. In this event, you’ll want to soak the particularly stained segment of your sail in a normal detergent. If this doesn’t work than try part water, part cleaning solvent (here is a good one). If you don’t have a cleaning solvent, and it’s a Dacron sail, you can do ten parts water to one part bleach (but need I remind you one more time to be cautious of its use?)

Prevention is Key: Ways to Prevent Your Sails from Becoming Damaged or Dirty

There is no better way to keep your sailboat sails immaculate than by preventing damage and stains in the first place. Here are some easy to follow, and sometimes rather obvious seeming ways to care for your sails.

  • Don’t leave your sails in the sun. The sun’s UV rays will severely damage your sails. You must make sure you have a sufficient protective cover for your sails anytime your boat is going to be docked for extended periods of time in the sun.
  • To this effect, avoid exposing your sails to unnecessary heat (like storing them someplace not temperature controlled – like a car trunk or outdoor storage unit). Likewise, be sure not to place them someplace silly like near a hot engine or heater.
  • When your sailboat is not in use (during the off season), remove the sails, clean them, and have them properly repaired at least once a year. And store the sails somewhere clean and safe. And never store them before they are 100% dry!
  • Roll and fold your sails properly – do not just shove them into a box or bag, this will help prevent a breakdown of your sail’s resin
  • Avoid petroleum-based products – the adhesives on laminated sails are liable to break down when you use such products

Key Take-Aways

Ultimately, the longevity of your sails is almost certainly determined by the state of care you give them, part of which involves preventative measures, and after-care for when your sail inevitably encounters dirt, salt, grease, or mildew. As long as you are keenly aware of the fabric your sail is made of, you should aptly be able to discern the best plan of action for cleaning your sails for your particular needs.

It is wise to avoid having to go through the time-intensive process of removing, cleaning, drying, and re-hoisting your sail, to do all you can to prevent damage, stains, and mess to occur on your sails. However, I understand sometimes things happen, and they must be cleaned. But now that you are now armed with the knowledge of how best to do so, you’ll have them spic-and-span in no time.


I am the owner of sailoradvice. I live in Birmingham, UK and love to sail with my wife and three boys throughout the year.

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