How to Use Flex Seal Spray

Put the phone down. Aren’t you tired of calling your repairman for every leak or break around the house? That gets expensive. Unless you don’t mind wasting thousands of dollars, there’s another way you can fix those pesky leaks without breaking the bank.


Flex Seal is a liquid rubber sealant coating that’s perfect for almost any DIY project inside or outside your house. Flex Seal can be used on almost every surface: wood, metal, tile, concrete, masonry, fabric, glass, plastic, aluminum, porcelain, drywall, rubber, cement, and vinyl. Plus, it won’t sag or drip in the summer heat, and it won’t crack or peel in the winter cold. It even prevents corrosion. There are many practical and creative ways to use Flex Seal. But what counts most is that you use it properly.

Make sure to have all of the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.

Step 1: Prepare Your Project Area

Before using Flex Seal, make sure that you have a well-ventilated area. Your garage could be the perfect space (with the door open). Or you could use a room in your house with windows opened and a fan running. If you’re more of an outdoor kind of guy (or gal), try your backyard. But make sure you pick a dry weekend to do your project. That means no rain, sleet, snow, dew – you get the picture. Once you’ve picked your area, cover it with a drop cloth. If you are spraying an entire object this will prevent you from spraying Flex Seal on any unwanted areas.

Step 2: Clean The Surface

Wipe off any dirt or dust from your surface. If the dirt is a little hard to get off, wipe the surface down with a damp rag and cleaning solution.

Flex Tip: If there’s any rust on your surface, sand it off before moving ahead. Sanding your surface will increase adhesion for Flex Seal.

Once your surface is clean, wipe it dry. Flex Seal works on wet areas, but it’s more effective on dry surfaces. Depending on your project type, you may need painter’s tape to section off the areas you’re looking to treat. For example, if you’re fixing leaks in a gutter outside, you’d tape off the edges around the gutter before you start spraying the holes with Flex Seal.

Step 3: Spray It

Shake your can of Flex Seal vigorously for about a minute. Then aim the nozzle at your surface and spray it in a sweeping motion from a distance of 8 to 12 inches. Take your time to focus on those holes and the larger surrounding area around them. Feather the edges. Let the first coat dry for 24 hours before applying the next coat. Allow 48 hours to fully cure.

If you have any questions, you can reach our customer service team at (833) 411-3539.