Best Waterproof Tent Sprays

How to Choose the Best Waterproof Tent Spray for You

Aerosol vs Spray Bottles

When it comes to waterproof tent sprays there are usually two methods of application. You can either buy the spray in a pressurized aerosol bottle or you can buy a spritzer bottle that you hand-spray.

Aerosol bottles are usually metal cans that have been pre-pressurized with some type of gas. Today companies are better about what types of things are used to pressurize these bottles, but in the past (and to some extent still today) aerosols are known for being pressurized with harsh chemicals.

Most of us outdoor enthusiasts probably prefer to minimize the spraying of weird and unknown chemicals so there’s another choice.

The spray bottle is your classic household cleaner style bottle with a little hand spray lever. Pull the lever and the bottle spritzes out some fluid – in this case a waterproofing spray.

The disadvantage of hand spray bottles vs aerosol is that aerosol applications can be engineered to produce a much finer mist of particles. This fine mist usually does a better job of applying an even and penetrating layer of waterproofing substance than does the hand applicator bottle.

Silicone Based Sprays

As we’ll talk about later, the best waterproofing for tent fabrics comes from silicone products. Silicone is a soft waterproof material that’s used in all sorts of household stuff – even oven mitts!

While there are many different waterproofing sprays out there, most of the best ones for use on tents are based on silicone. Be careful that you don’t accidentally get a “stain resistant” spray for use on clothes. These stain guard style sprays just won’t hold up to use on your tent.

Generally speaking tent waterproofing or boot waterproofing sprays apply a much thicker, heavier layer of waterproofing material than those meant for clothing stain protection.

Understanding Tent Fabrics

How effective your waterproof tent spray actually is will depend greatly on what you’re starting with. There are several different types of tent fabric and understanding them will help you know more about what you’re getting into.

Silnylon and nylon are man made fabrics that are very similar to the same material used in plastic bags. This material is processed into fibers which can be woven into nylon fabric of various thicknesses.

Silnylon is just nylon fabric that has been impregnated with silicone. This silicone is the important waterproofing element of the fabric.

Silpoly and polyester is a similar man made fabric in many ways. It’s less stretchy than nylon under loads and when wet. However, it can be a bit more expensive and only certain specific weaves of silpoly make ideal tent bodies.

Both silnylon and silpoly make good tent bodies but the quality of the fabric and the silicone impregnation are an important and often difficult to understand factor of the overall picture. Many manufacturers offer very little information about the details of their fabric types.

A rarer but important tent fabric known as Dyneema Composite or Cuben Fiber is even more waterproof than either silpoly or silnylon. This ultralight fabric is also ultra expensive but is made from a fully waterproof impermeable sandwich of plastic mylar and dyneema fibers. Cuben fiber never needs waterproof spray.

Duck Cloth Tents

A word to those of you who might be using old military surplus gear such as the old duck cloth tents. These waterproof sprays will not make your tent waterproof.

Waterproof sprays like this work by creating a chemically bonded layer of waterproof material on the surface of the fabric. On very tightly woven fabrics like modern nylon and polyester, this works great!

On fabrics with larger weaves, like cotton and duck cloth canvas, the space between each fiber is enormous compared to nylon and polyester. These waterproof sprays cannot properly fill and protect those larger weaves and you’ll soon be disappointed when your tent eventually begins to leak again despite your efforts.

Difference Between Seam Sealing and Waterproofing Spray

You’re probably researching waterproof tent sprays because you’ve realized your tent has a leak. But will waterproof tent spray actually help?

Before you go with waterproof spray you need to be sure the leak is not coming from a puncture or seam.

Punctures are easy to spot and can be caused by sticks, branches, tent stakes, or clumsiness. Leaks along the seam of your tent might be harder to identify.

Seam tape is a thin strip of waterproof material applied at the factory over the sewn seams of your tent. Invariably this tape will lose its stickiness and begin to peel off after a couple of seasons, even if you don’t use the tent. Check the seams of your tent to see if your seam tape is beginning to peel.

Silicone seam sealing can be done at home or at the factory and usually provides much better results. Diluted silicone is brushed onto the seams in a thin layer which penetrates and seals the puncture holes left by the sewing machine. This method can be used to repair old seam tape that is beginning to peel.

Now that you’ve inspected and repaired your seams, if the leak is still occurring then you probably need to re-waterproof your tent with a spray.

How to Apply Waterproof Tent Spray

To get the best results from your waterproof tent spray you’ll need to follow a couple of simple steps.

1. Set up your tent outdoors in the sun for a few hours until it’s completely dry.
2. Bring your tent into the garage or other covered space with minimal wind and sun exposure (direct sunlight can be hard on the waterproof spray chemicals).
3. Spray in generous even strokes, overlapping each pass by an inch.
4. Do not overspray! Drips and runs should not be present. If you notice a buildup of excess spray on the fabric move your spray faster or back off a few inches.
5. Let the spray dry overnight before taking your tent down and packing it away.

It’s okay to apply more than one layer of waterproof spray as well. If you feel that your tent needs extra waterproofing or if one layer didn’t work well enough repeat the processes as many times as needed.

Can I Waterproof a Tent That Wasn’t Already Waterproof?

The simple answer here is no. If you buy a crappy tent and it’s not actually made from quality waterproof materials then no amount of waterproof spray will help.

If your tent originally was waterproof and it just needs a little help getting back on track, waterproof spray should help extend its life a few more seasons.

To avoid this problem, make sure you fact check manufacturer’s claims. If you go to buy a tent and the manufacturer doesn’t clearly state what kind of waterproof fabric the tent is made from then just skip it. It may be junk.

FAQs

Can I use these waterproof sprays on breathable fabrics like Gore-Tex?

The answer is unfortunately long and complicated. For breathable fabrics to work properly, the outer layer of nylon or polyester must remain dry (or at least not saturated).

Over time waterproof breathable garments may lose their water resistance on the outer layer and “wet out”. Once this happens the garment may still be waterproof but it will lose its breathability. To restore breathability you’re best off using a wash-in DWR treatment.

Do these sprays smell bad?

Good question. The answer is yes and no.

Most of them have some minor odor when sprayed on at first. Over the 24-72 hours while they cure the odor should almost entirely disappear. Once cured all of the sprays on our list should have little or no smell at all.

If you spray your tent and then pack it up before the spray has a chance to fully cure it may continue to smell for a while.

How many coats of spray should I use?

For most of the heavy duty silicone based sprays on our list you should be good with one heavy coat. Adjust your spray distance and speed to apply a nice thick layer, but don’t get the fabric so wet that you get drips and runs.

Using a heavy application like this should yield good results with just a single pass over the entire tent fly surface.

Conclusion

When it comes down to it often you’re better off buying a new tent with a high quality rain fly to make sure you stay dry. But that’s expensive and most of us don’t want to cough up the cash! Waterproof tent spray can be as cheap as $5 and it just might save your tent for another season.

If you follow our buyer’s guide and read through the reviews to find the best waterproof tent spray for your equipment, you should be successful at restoring the quality of your rain fly.

Remember that at some point tents get too old and too worn out to save and you’ll eventually have to give in and upgrade your equipment. Waterproof tent spray isn’t magic but if you understand its limitations and use it preemptively it can help extend the life of your gear!