How Local Conditions Play In
Northbrook sits in a cold-moderate climate band, and that's the whole story behind most draught calls we get. It's not one brutal week of arctic air that wrecks a seal - it's the repeated freeze-thaw cycle every winter, where the rubber bottom seal goes rigid overnight, gets driven over by the door's own weight in the morning, and slowly loses its memory. Vinyl and rubber seals are rated for flexibility across a temperature range, and this area asks them to flex across a wider swing than a warmer climate would.
Housing age matters just as much. Most homes in the service area were built between 1938 and 1996, with the bulk of that stock going up in the 1960s and 70s. A door frame poured in 1968 has settled differently than one poured in 1990 - concrete aprons crack, slabs tilt a fraction of an inch, and the seal that was cut to fit a level threshold decades ago is now trying to close against a gap that isn't uniform anymore. That's a maintenance issue tied directly to the age of the slab, not a defect in the seal itself.
What Most People Get Wrong
The most common mistake is blaming the opener. Someone feels cold air along the bottom of the door in January and assumes the travel limits are off or the motor is weakening. In a house built before 1996 - which is most of them here - that's almost never it. The opener closes the door to the same spot every time; what's changed is the seal or the threshold underneath it, not the mechanism pulling the door down.
The second mistake is treating the seal as a one-size job. A lot of these older Northbrook garages have already had one seal replacement over the decades, often with whatever bulb-style gasket was on the shelf at the time, and it may not match the track profile the door was built with. Pushing a new seal into a track it wasn't designed for looks fine for a season and then peels or bows. And people often try to fix a draught with foam tape along the sides when the actual gap is at the bottom corners, where the slab has settled unevenly - foam tape there just buys a few weeks before it tears.
When to Get Help
If your house falls in that 1938-1996 build range - and most in this area do - and the draught is at the bottom corners rather than dead center, that's a seal or threshold problem, not a panel or opener problem, and it's usually a straightforward swap. If the cold air is coming through gaps along the full width of the door evenly, the issue is more likely the door's alignment against the track, which is a different job.
One honest limit: if the slab itself has heaved or cracked badly enough that no seal profile sits flush anymore, a new seal won't fix the draught - that's a concrete problem, and we'll tell you that instead of selling you a seal that won't hold. For most seal-only jobs, though, it's a same-visit fix. If you're not sure which one you've got, we can take a look.
