In some cases it is important to seam seal your tent or tarp. Usually after using your shelter for a prolonged period (dozens of nights) or if you plan on camping in a very wet location. Usually seam sealant is needed where the needle pierced the fabric while manufacturing. The sewing maching created dozens of small holes in the fabric. Over time, strain in the material allows those small holes to become slightly larger. This may cause your tent to leak in heavy, prolonged rains. This happens with almost all tents, but we’ve noticed that almost no one educates their customers on this vital step. We even go the extra mile of including seam sealer kits with all of our tents! Let’s learn how to seal those holes tight!
Learn Your Tent Fly Fabric
Be sure to check with your tent manufacturer, to learn which type of sealer is applicable. This is important! For example, Luxe Hiking Gear tents use a fabric that requires a silicone-based sealer (approved for PU coated fabrics). We sell silicone-based seam sealer in our shop.
Preparing the Fabric for Sealer
It is important that you pre-clean the tent fabric in areas you will be sealing. Set your tent up outside, somewhere you can leave it for a prolonged period and the weather forecast is fair. The tent needs to be taught and wrinkle free, to insure a nice smooth seal. We like to use isopropyl rubbing alcohol for cleaning the fabric. This is readily available and evaporates quickly. Pick some up at any pharmacy.
Don’t Make a Mess
It can be very easy to get seam sealer on the tent fabric, where you may not want it. Some tips to prevent this include applying masking tape beforehand and removing the tape after 30 minutes of drying. Or pre-cut a skinny rectangle stencil using thick paper or card you have lying around, and just move your stencil around and paint strips of seam as you go.
Don't over apply sealer, you just need enough to fill the stitching holes.
Seam Sealing Your Tent
Now you are ready to apply seam sealer to your tent seams. Use a small brush, to make sure the sealer penetrates the small thread holes. Generally you want to apply sealant to the outer tent rain fly where it has been sewn. Pay special attention to the peak of the tent and where the guyline loops pull, since the fabric is under stress in these areas, those are the highest priority spots if you only have a small amount of seam sealer. You only need to apply seam sealer on the outside of the tent. Some people seam seal their bathtub or inner tent floors, where the fabric is close to the ground. Doing this will keep your area dry during heavy rain storms.
After the Seams are Sealed
Leave your tent set up for 12 to 24 hours, or until the next day. Inspect and visually test the area, to make sure you did not miss any areas. It may be necessary to re-apply in some cases. Seam sealant is tacky (sticky) to the touch, even once it is dry. Some people rub baby powder or cornstarch on afterwards to prevent the sticky feeling, but keep in mind that it will leave a soft white appearance on all your seams.
Not drying? Chances are that you over applied. Try wiping excess with a shop cloth or rag.