2026-03-17 7 min read
If you live on the east side of Covina near Charter Oak or in the older ranch-style neighborhoods off Badillo Street, you already know how relentless the summer sun gets. Temperatures regularly climb into the low 90s from July through September, and the San Gabriel Valley's trademark heat-trapping geography means your garage door faces conditions that doors in cooler climates never have to deal with. Most homeowners don't think about it until something breaks — but by then, the damage has been building up for years.
Covina sits in a classic Southern California Mediterranean climate — short, hot, dry summers and mild winters where most of the year's rain falls between November and March. That means your garage door spends the majority of the year baking under direct UV radiation with very little moisture relief.
UV exposure is one of the sneakiest threats. Day after day, ultraviolet rays bombard the door's surface, causing colors to fade, materials to deteriorate, and potentially compromising structural integrity over time. For the midcentury ranch-style homes that dominate Covina's neighborhoods — most built between the 1940s and 1980s — many garage doors are working with materials and finishes that are decades old and long past their UV-resistance prime.
On metal doors, UV rays break down the paint's chemical bonds, causing fading and chalking. In severe cases, the protective coating deteriorates enough that the metal underneath becomes exposed to moisture, which means rust. On wood doors, UV rays break down lignin — the natural compound that holds wood fibers together — leading to surface graying and deep structural cracks.
Beyond surface damage, the heat itself creates mechanical problems. When temperatures rise, metal components — springs, tracks, and panels — expand. This expansion can cause the door to warp or become misaligned, leading to operational issues. High temperatures also cause lubricants to evaporate or break down faster than they would in milder climates. When lubrication fails, friction increases, and that puts added strain on your opener motor and springs.
Another problem specific to sunny climates: direct sunlight on your garage door's safety sensors (the infrared eyes near the floor) can overpower the beam, causing the door to refuse to close unless you hold down the wall button. If your door has been acting up on sunny afternoons specifically, that's likely the culprit — not a broken sensor.
The good news is that most heat and UV damage is preventable with some routine attention. Here's what actually works:
Standard lubricants can thin out and lose effectiveness when temperatures push past 85°F. Choose a lithium-based or silicone spray rated for high temperatures, and apply it to the rollers, hinges, tracks, and springs at least twice a year — once before summer hits and again in the fall. Don't skip the smaller hardware like bolts and brackets; heat can expand those metal parts too, causing subtle misalignment that wears everything out faster.
The rubber seal at the bottom of your door takes a beating from Covina's heat. Check it for cracks, brittleness, or any sections that have started to detach from the door. A compromised bottom seal doesn't just let hot air in — it allows dust, insects, and pests to enter your garage. Replacement seals are inexpensive and can be a DIY job if the door frame is in good shape. Check the side seals too; they get forgotten but degrade just as fast.
If you have a painted steel or wood door, a UV-blocking topcoat can meaningfully extend its life. Polyurethane and clear acrylic coatings are both popular options — they create a barrier that reflects UV radiation and slows the breakdown of the underlying finish. For steel doors especially, this also reduces the risk of rust developing under peeling paint. A good wash with mild detergent before applying any coating helps the product bond properly.
If you're in a spot where the afternoon sun hits your garage opening at a low angle — common in west-facing garages across Covina and neighboring West Covina — pick up an inexpensive sun shield for your safety eyes. This is a five-minute fix that prevents a lot of frustrating "door won't close" calls. You can also adjust the angle of the sensors slightly downward to reduce direct sun exposure.
Many of Covina's older homes were built with uninsulated single-layer garage doors. An insulated door — or an insulation kit added to your existing door — keeps your garage significantly cooler, which reduces strain on the opener motor and helps protect anything stored inside, including your car's interior and any electronics. For an attached garage, it also reduces heat transfer into your home, which shows up on your utility bill.
For a full rundown of routine care tasks that extend door life, check out our garage door maintenance checklist — it covers everything from spring inspection to opener testing in one place.
If your door panels are already visibly warped, faded, or cracked, it's worth getting a professional set of eyes on it. Minor panel damage can sometimes be repaired in isolation, but if the heat has warped the frame or caused alignment issues in the tracks, you may be looking at a more involved repair. Our services page has details on what Garage Door Covina handles, from panel replacement to full door inspections.
Don't wait for a full breakdown in the middle of a 95-degree July afternoon. A quick inspection in spring — before temperatures peak — is the smartest thing you can do for a door that's already showing its age.
Q: My garage door works fine in the morning but struggles to close in the afternoon. What's going on? A: This is a classic sign of sun interference with your safety sensors. When direct sunlight hits the infrared beam connecting the two sensor eyes, it can disrupt the signal and make the system think there's an obstacle in the door's path. Adding a small sun shield to the sensors or slightly adjusting their angle usually fixes it immediately.
Q: How often should I lubricate my garage door in a hot climate like Covina? A: Twice a year is the minimum — once in spring before the heat builds and once in fall. If your door is used heavily (multiple times a day) or if you notice any squeaking or stiffness during summer, add a third application in midsummer. Always use a product rated for high temperatures, not standard WD-40.
Q: Can I paint my garage door to protect it from the sun? A: Yes, and it actually helps quite a bit. A lighter color reflects more heat than a dark one, and using a paint with UV inhibitors or adding a clear UV-blocking topcoat can significantly slow down fading and surface cracking. If your door has existing rust spots, treat those with a rust-inhibiting primer before painting — otherwise, rust will push through the new paint within a season.