Repairs · Cannington
Garage Door Bottom Seal Replacement in Cannington
The gap under the door is a finger wide at one end and nothing at the other.
In plain words
The bottom seal, called an astragal in the trade, is the flexible strip along the underside of the lowest door section that squashes against the floor when the door closes. On most steel doors it is a U-shaped vinyl or rubber profile whose two edges slide into the channels of a retainer fixed to the bottom rail; on wood doors it is often a flat angled strip nailed in place. Replacing it means matching that retainer and profile, fitting a fresh seal the full width of the door, and confirming it meets the floor in one continuous line so light, drafts, water and pests lose their route in.
How the visit goesWith the door closed and the lights off, a bright line of daylight runs along the floor from one side to the other. Leaves and grit have blown in under it and gathered in a neat drift against the back wall.
Garage Door Bottom Seal Replacement
How the visit goes
Why the old seal failed
The old strip is read for its history before it comes off. Cracks along the fold and a chalky surface point to sun and age. A flattened bulb that no longer springs back is compression set. A torn edge at one end usually means the seal froze to the floor and the opener pulled it free. Chew marks say rodents. A strip that has slid partly out of its channel points to a bent or opened retainer, or to a seal that was slightly the wrong size. Each of these leads to a different choice of material, profile or retainer work, so the new seal is spared the fate of the old one.
Cutting the new seal to length
The replacement is cut from a roll to the door width plus a small allowance at each end, using heavy shears or a knife, and the profile is checked against the retainer before any feeding begins. The technician confirms the T or bead edges match the channels and that the bulb height will fill the gap measured earlier without being squashed flat. Where the floor dips at one end, a slightly taller profile is chosen rather than relying on the opener to press harder. Cutting a little long means the ends can be trimmed to the door and finished cleanly once the seal is in.
The rest of the weather line
With the bottom sealed, any remaining draft points to the perimeter: the vinyl fin on the stop moulding at the jambs and header, and the joints between sections. These were looked over during the visit and anything torn, shrunk or missing was pointed out. Replacing perimeter stripping is straightforward work that can be planned for a mild day. Together with a sound bottom seal and, where the floor calls for it, a threshold, the garage gains a stronger barrier against wind, water and cold on all four edges, and an attached garage can stay closer to the temperature of the house.
Garage Door Bottom Seal Replacement
In the van
Wire brush and scraper
T-style bottom seal
Aluminum bottom seal retainer
Seal end caps
Bulb or U-style bottom seal
Garage Door Bottom Seal Replacement
What affects the quote
Condition of the old seal
A supple strip slides out in a minute. One that has hardened and seized in its channel, or been torn and frozen into the corners, has to come out in pieces, which takes longer.
Floor and threshold shape
A dished, sloped or heaved slab may call for a taller bulb profile or a threshold seal on the floor, each of which is quoted as a separate choice you can accept or leave.
Perimeter seals done together
Jamb and header weatherstripping renewed in the same visit is quoted per length of stop moulding, and doing it alongside the bottom seal saves a second call-out.
What to have ready
- Does the door stop short of the floor or reverse before it closes?
- Is the old seal hard and cracked, torn, hanging loose, or missing?
- Are the side and top weather strips also worn or torn?
Garage Door Bottom Seal Replacement: questions
QuestionsHow do I look after the new seal?
Wipe it clean of salt and grit a few times a year, and give it a light coat of silicone spray each autumn so meltwater has nothing to bond to. Keep petroleum products and solvents away from it, since they soften vinyl. Clear ice and packed snow from the threshold before running the door in winter. Once a season, look under the closed door for daylight. That is the whole routine.
Why does the seal freeze to the floor, and what should I do when it does?
Snow melts off the car, runs to the low point at the door and refreezes overnight around the seal. When that happens, leave the remote alone, since the opener will tear the strip or pull the door out of level. Free the seal by hand with gentle warmth along the line or by working a plastic scraper under it, then run the door. A film of silicone on the seal each autumn largely prevents it.
What does a new bottom seal do about water coming in?
It closes the gap between the door and the slab so rain and meltwater meet a continuous barrier. Where the driveway slopes toward the garage, or the slab edge has dipped, the seal alone is working against gravity, and a threshold seal glued to the floor adds a lip that turns water back toward the drive. The technician looks at where the water comes from and recommends the combination that suits your threshold.
Related services
- Garage Door Tune-UpSince the first cold snap the door has been sluggish.
- Off-Track Garage Door ResetYou tapped the door with the bumper while backing in, barely a nudge, and now the bottom corner has swung inward.
- Garage Door Panel ReplacementYou misjudged the last metre of the driveway and felt the bumper meet the door.