Why Your Garage Door Lets in Draughts (And What to Do About It)

Checking It Yourself

Start at the bottom of the door. Most houses in this part of Plano went up between 1973 and 2015, with the bulk of that stock dating to the early 2000s, so the bottom astragal on your door is likely the same vinyl strip the builder put on. Push a flashlight against the seal from outside at dusk and look for light coming through from the garage side. Check the corners first - that's where the seal pulls away from the track first. Run your hand along the top and side jamb weatherstripping too. If it's stiff instead of pliable, or if it's cracked into short segments instead of one continuous strip, it's not sealing anymore, it's just decoration. A door that closes flush but still lets in dust or light along one edge almost always has a seal problem, not a spring or opener problem, so don't call about the opener when the fix is a ten-dollar strip of vinyl.

What Is Going On

Vinyl and rubber seals don't fail all at once. They harden with age and sun exposure, and once they harden they shrink slightly and stop conforming to the concrete or the track the way they did when new. On a house built in the early 2000s - which describes a large share of homes in this area - that seal has had two decades of expansion and contraction cycles to work through. The bottom seal takes the worst of it because it's in direct contact with the slab and gets compressed every time the door closes. Side and top seals fail more from UV exposure through the small gap where the door sits in the frame. None of this is a defect in your door. It's just what happens to rubber and PVC over years of daily use in a climate that runs hot for a good part of the year.

The Seasonal Bit

This area sits in a moderate heat climate band, not a hard-freeze one, so the seasonal story here isn't about ice splitting a seal - it's about sustained heat softening and then re-hardening the material over and over. A seal that spends long summer stretches warm and pliable, then cools at night, goes through a small expansion-contraction cycle every single day. Do that for fifteen or twenty years on a door built in the early 2000s and the material fatigues even without any single extreme event. I don't have data on how many freeze days this area sees in a given winter, so I won't tell you your seals are at risk from ice - they're not, particularly. The wear pattern here is steady heat cycling, not sudden cold snaps.

What the Weather Here Does to It

Heat does two things to an older garage door beyond just aging the seals. First, it expands the metal track and the door panels themselves, which can shift alignment just enough that a seal that used to sit flush now has a small gap at one corner. Second, sustained heat on aluminum or steel track fasteners can loosen them slightly over time, which compounds the seal gap problem - you get a draught that looks like a seal issue but is actually a track alignment issue. On homes built through the early 2000s that are now well into their second decade or more, we see both issues together more often than either alone. Honest limitation: if the panel itself has warped from heat exposure over the years, a new seal won't fix the fit - at that point you're looking at panel replacement, not a reseal, and I'd rather tell you that up front than sell you a strip of vinyl that won't solve it.