If your zipper looks like the image above then it is not waterproof.
Most zippers have a good level of water resistance however if you walk into a rainstorm with a zipper like this water will get through.
Rubbing silicone wax or beeswax over your zip, or covering the zip with waterproof tape are good methods of keeping water out.
If your jacket or bag is equipped with an inadequate zipper then here are three things you can do to waterproof your zipper:
1. Use Wax
Wax is the quickest and easiest zipper waterproofing solution.
Silicone wax, beeswax even soap (if you’re short of options) will help seal up your zip and repel water.
Wa has been used for waterproofing for centuries and to this day is still used to waterproof jeans, Barbour jackets and more!
To wax your zipper take a small amount of wax and rub it up and down the outside of the zipper teeth until all teeth are covered.
Make sure you rub it in well so that it gets into the cracks between the teeth as this is where water penetration occurs.
Be careful not to apply too much or it will get all over your coat which is not ideal.
Once you have finishing applying the wax rup the zip up and down the zipper a few times to help evenly spread the wax and embed it in and around each tooth.
One additional bonus to using wax is that it also help lubricate your zip so it should run nice and smooth after applying the wax.
2. Use A Zip Covering / Storm Flap
Most outdoor coats will come fitting with a zip covering, also known as a storm flap.
This is a fabric flap that runs alongside the zip. When the zipper is closed you can cover it with the storm flap.
Many include velcro attachements for extra rain protection.
The combination of zipper, storm flap and velcro is pretty much impenetrable to rain even if the zipper is a standard (non-waterproof zip).
However if your jacket doesn’t have a storm flap you could sew one on if you know what you are doing!
If you want to go down this route then check out this tutorial on how to add a storm flap to your jacket.
Alternatively, for a short-term solution, you can just stick some waterproof tape such as Flex tape over your zipper to keep the rain out.
3. Replace The Zipper With Purpose Made Waterproof Zipper
Most zippers are not waterproof however waterproof zippers do exist, they look like this..
Waterproof zippers have the coils (teeth) hidden at the back of the zipper, a rubber or PVC coating covers the front of the zip when it is closed making it completely waterproof.
If you want to replace your zip with a waterproof zip we recommend you take your jacket and the zip of your choice to a tailor, however if you want to do it yourself then follow these steps:
- Buy a waterproof zipper that is the correct length for your coat, get a zipper which is as close in length to what the supplier offers as possible (get one that is slightly too long rather than too short).
- Remove the original zipper. To do this you will need a ripper tool, this will slide between the seam where the zipper meets the jacket, use it to slowly break the stitching so that you can release the zipper from the undertab.
- Sew your waterproof zipper in. It is a good idea to use an anti-wick thread as these use additives which help prevent water from traveling through the seams.