How to Install a Garage Door Bottom Rubber Gasket


As you go about your day-to-day activities, you may not pay much attention to the astragal, which is the technical term for the bottom rubber gasket of your garage door. According to DDM Garage Doors, Inc., the garage door gasket not only acts as a garage door seal but also safeguards the bottom of the garage door from damage caused by impact with the floor each time the door is closed. When the astragal becomes worn, it creates very small gaps that enable dust and debris to fly into the garage. When the bottom rubber gasket is deteriorated, it makes it easier for water to leak in, even rainfall.

  1. 1. Take Your Measurements

    Take a measurement of how long the door is. Obtain a door gasket seal that is that length plus at least an extra 6 inches in length beyond that.

  2. 2. Shut Off the Power

    If you have an electric garage door opener, make sure that the power is turned off to the door. Pull the plug on the garage door opener, or turn off the power to it at the circuit box.

  3. 3. Disengage the Door From the Opener

    Find the handle that’s attached to the door and holds the garage door opener in place. This is often a bright red handle that is fastened to a rope and dangles from the ceiling above the garage door. You may open the door manually by pulling down on the handle of the rope, which will disconnect the door from the automatic door opener.

  4. 4. Raise the Door

    Raise the door so that its base is just a hair’s breadth below the point where the vertical track starts to curve away from the roller track. While you are replacing the garage door gasket, you should use vise grips to prevent the door from falling while it is being held in place on the track below it.

  5. 5. Straighten the Tracks

    Using a screwdriver, pry open the grooves that act as a track for the bottom rubber gasket on each end of the garage door. These slots are located on either side of the door. By using the screwdriver to realign the tracks that run down the bottom of the door, you will make it simpler for yourself to install the new garage door seal.

  6. 6. Remove the Old Gasket

    To remove the old gasket from the garage door, pull it off. If it does not move out to either side, you will need to use a utility knife to cut the gasket into two pieces that run down the length of it. The old gasket may be taken out in pieces using the slider.

  7. 7. Clean the Tracks

    Clear away any material that may still be stuck on the underside of the door. The two tracks that hold the weatherstripping need to have the debris removed.

  8. 8. Apply a Lubricant

    Spray the inside of both tracks with a silicone lubricant, being sure to cover the whole surface. You may also use a spray bottle full of water and add one or two drops of dish detergent or another kind of soap to the mixture. The soapy liquid may be used as a lubricant if it is sprayed over the track.

  9. 9. Fold the Gasket in Half

    On one end, fold the new gasket in half to create a crease. Place one of the rubber flanges that are attached to the gasket onto one of the tracks, and then place the second flange onto the track that is parallel to the first. Put the replacement gasket on the garage door by sliding it onto the bottom of the door. Hold the new gasket at the same height as the track around 12 inches outside the door to make it simpler to feed it onto the track. This will give it a straight shot onto the track, which will help the process go much more smoothly.

  10. 10. Install the Seal

    You need to move the bottom seal about 3 inches beyond where the track ends. After folding the seal back upon itself, draw it back until it is level with the door’s side and then fold it back again.

  11. 11. Cut Away the Excess

    At the point where you fed the gasket onto the track, cut off all but three inches from the end of the gasket. To adjust the gasket, pull it back from the track by three to four inches. The end of the gasket has to be folded back upon itself. When you have the gasket in its final position, which is achieved by pushing it back onto the track and aligning both sides of the gasket with the door’s sides, you may close the door.

  12. 12. Lower the Door

    Take the door out of its current position by removing the vise grips. Bring it down to the ground level. Bring the door into alignment with the opener. The garage door opener requires that the electricity be turned back on.

  13. 13. Check and Make Adjustments

    Repeat moving the door up and down the track. Adjusting the restriction on the door opener according to the instructions provided by the manufacturer may be necessary if the door goes down but then opens back up again.

    Things You Will Need

    • Tape measure

    • Vise grips

    • Screwdriver

    • Utility knife

    • Silicone lubricant spray

    • Dish detergent

    • Spray bottle


    Ridgeline suggests searching for a rubber gasket that can withstand high temperatures, is constructed from many layers, and is so durable that rats won’t be able to nibble through it.