Introduction: Easy Waterproof Clothing
While I was making my glow tie I realized that the solution I made to apply the glow power to the fabric was incredibly hydrophobic, which makes sense as it's silicone based. After some experimentation I found it was a great method for waterproofing all kinds of close knit fabrics, like tote bags and other large flat fabric surfaces.
I'm not that impressed with most commercial versions of waterproofing, and this method gives me full control of the efficiency of my waterproofing. Inexpensive, flexible, and easy to make, this homebrew solution is a great way to make almost anything waterproof.
Ready to waterproof all the things? Let's make!
Step 1: Supplies
Making your own waterproof solution requires 2 things:
- 100% clear silicone sealant (must be 100% silicone)
- Mineral spirits
You'll also need the following supplies:
The glow powder is added to a liquid medium which is then applied to the tie. The medium is made from silicone caulking which is diluted in mineral spirits.
You'll want to use 100% clear pure silicone caulking. Look for "silicone I" as "silicone II" has mold retarding agents, we want pure silicone. The silicone can be thinned with mineral spirits. You can find both the caulking and the mineral spirits at your local hardware store.
Step 2: Mixing Solution
To make a medium that can be brushed onto the fabric, we'll need to thin the silicone caulking with plenty of mineral spirits.
I started with a ratio of 5:1 - 5 parts mineral spirits to 1 part caulking. Put both into a mixing cup and mix thoroughly. At first this is going to look like too much mineral spirits and not enough caulking, but silicone is incredibly thick and after a few minutes of mixing the solution will begin to thin.

You're looking to achieve a very runny medium with no clumps, lumps, or anything even resembling the caulking. The GIF above should be the viscosity you are looking for, something like very runny maple syrup. It is also going to smell terrible, so make sure to work in a well ventilated area.
Step 3: Brush Onto Fabric
I used a bristle chip brush to apply the medium onto the tie. Chip brushes are meant for resin, acetone, and epoxy, so are a suitable choice for this application.

The brush was dipped into the mixture and generously applied all over the fabric. The fabric was hung to dry, making sure that the fabric was not overlapping anywhere - any overlapping fabric will bond together when it dries.

Special attention was given anywhere there were stitches, since this will be a weak spot in the waterproofing. After drying, multiple coats were applied to the fabric to ensure a good waterproof seal. Additional coats were put on seams and stitches to make them more durable.
The smell from the caulking is still pretty terrible even after a day of drying, but goes away after about a week.
Step 4: Hang Dry
The fabric was left to dry for an entire day after each coat, allowing the silicone to cure completely.
Step 5: Waterproofing Thoughts
This was a fun exploration into homebrew waterproofing. The process is simple, and the results are much better than commercial options. However there's a significant drying time between coats, which makes this a good waterproofing option if you prepare ahead of time, not in the heat of the moment.
Share your comments and results below.
Happy making!
162 Comments
Question 4 months ago on Step 5
Will this work on a boat canopy
Answer 2 months ago
yes it will
3 years ago
Will this work on nylon/tent fabric? I was concerned that the solvent would possibly dissolve the fabric.
Reply 7 months ago
I've seen it done and it works amazingly well. None the less I second the notion to first test in an innocuous location.
Reply 7 months ago
Or even in an inconspicuous location lol
Reply 3 years ago
Test on a small piece of item in an inconspicuous location.
4 years ago
Could this be used in a spray bottle instead of brushing
Reply 3 years ago
Yes you can. I mixed a quart of oderless mineral spirits ( even though there's still an oder LOL) and a whole caulking tube of 100% Silicone and thought maybe it would be too thick to spray. I poured the mixture into a 1-gallon spray bottle after a thorough mix with a paint stick, pumped it up and squeezed the trigger and a fine to medium spray came out! It couldn't have been better! Waterproofing my canvass BBQ cover, but should have bought extra mineral spirits + a standard tube of silicone to add to fully cover the whole BBQ cover. I sprayed it about an hour ago and it's starting to dry already and look natural to the area I didn't hit. Luckily I find that I can mix more and start off where I left off. YES, I recommend using the spray bottle!!!!! NO MESSY BRUSHES and cuts your time sign=significantly shorter and sprays much more evenly!! Now I'm trying to see if I can salvage my spray bottle after a heavy rinse. If not, fine. I'm thrilled anyway!
Reply 1 year ago
Hey Scott, can this mixture you talk about stored? Cause I prepared mine and applied it succesfully on a test area with a spray bottle but the next day was impossible to spray, the silicone was very viscous and I had to use a brush. I tried adding more solvent but didn´t work. Also after 2 or 3 days of preparation was impossible to apply with a brush cause the mixture was like a gum or a slime. I mean, should this product be used ONLY the same day of preparation or can be stored or modified to be stored? of course these sillicone tubes are made to dry and toughen to glue stuff but did you keep yours or did you throw it away the same day?
Reply 7 months ago
Keep in mind that silicone doesn't dry it cures so it's not the evaporation of the mineral spirits that is causing the silicon to become hard and solidify it's a chemical reaction when the silicone is exposed to air. It is almost impossible to completely prevent air and the silicone interacting as you will find if you open an old tube of silicone. You even if it hasn't been opened it will have gone hard around the edges and really old tubes can becomes a single solid mass (which an be fun to carve and make into molds). You could try vacuum sealing the mixture in a bag but it seems like a lot of effort for just a few dollars worth of silicone and turps (aka mineral spirits). In my opinion a better solution would be to try and make up only as much as you need to use and dispose of any leftover solution or even better find something else to waterproof.
What I would like to know is if this preparation is dangerous particularly to animals and even more particularly to reptiles. The I have just completed the internal decoration of my lizard enclosure using acrylic paint which I now want to make waterproof to prevent the paint running when I water the plants. The tyre ways I've considered are simple clear spray paint (which I Ave used before), and I a commercial waterproofing spray, or this method. I was leaning towards this method because most aquariums are made with silicone because it's non toxic. But I'm concerned that the mineral turps is vapour will persist and harm the geckos when they are returned to their enclosure. I'd be interested if anyone has got any opinions or alternative solutions. Cheers.
Reply 1 year ago
It's the silicone that made it to the tip of the spray bottle that's clogging the nozzle or the mineral spirits softened the plastic pieces inside the spray bottle. Try like "Zaps" brand spray bottles, (usually for sale at home improvement stores) their .5gal and made with stronger innards for harsher chemicals.
Reply 4 years ago
Possibly, but I think it might be too viscious
Question 7 months ago
Hi, I have a completely different requirement. Have you ever hear about Temporary Tattoo Paper!? It is a basic paper with a thin Silicone layer on it. You print on this paper over this silicone layer, put this paper (silicone and printed side facing) onto your skin and applied some Water and that print transfers onto your skin. I want to make this same thing on a Fabric. I really dont want to make the fabric waterproof but slippery, so that a print on that fabric can transfer to any skin.. Can you please help what ingredients will I need for this? Thank you in Advance.
Question 3 years ago on Step 5
I can’t get mineral spirits in Australia is it the same as mineral Turpentine?
Answer 8 months ago
Yep. I believe it is. Thats what I've used for this before.
10 months ago
I know this post is really old however no one commented or asked about the weight of the mixture. I have quite a few nylon inflatable yard decorations and a few are starting to sag due to the fabric thinning over time. i checked motor and all seams as well as for rips and there are no other issues. I have heard some say that this mixture is able to revitalize those inflatables, but obviously weight becomes a concern since the fans are mostly smaller. what are your thoughts on this?
1 year ago
Do you think this mix could be tinted with something like acrylic paint without effecting the waterproofing ability. The reason I ask is I do custom work on sport bikes everything from building race engines for track bikes to crazy lighting on street only rides, this includes seat covers. The problem I run into a lot is the fairings can be painted or custom ordered to be in any color you can imagine but it's very hard or very expensive if you can find marine grade vinyl in a matching color if someone didn't account for that before choosing what color or colors for the fairings. I can often find matching colors or close to it in fabric that's not suitable for all weather, and I can always find acrylic paint in a matching color. If adding the paint to the mix could tint it to match I could use it to not only waterproof fabric that wasn't made for that use but also use a fabric that was close to matching and with the waterproofing make it match or come much closer to matching. Just wondering if anyone would know automatically if it wouldn't work before I wasted my time on a pointless venture.
5 years ago on Step 5
I question using this on indoor furniture - is this fire-retardant?
Reply 3 years ago
Mineral spirits are petroleum-based products like naphtha which is highly flammable!
Reply 2 years ago
True, but the mineral spirits evaporate in the drying process so those are not relevant for the indoor stuff when drying is over. It is the silicone you should think about. According to wikipedia polydimethylsiloxane is non-flammable, however it does score a 1 in the fire diamond. Cellulose, the main component of cotton, also scores a 1. So I guess that should give an idea, it is probably not more flammable than fabric itself.