Garage Door Safety for Dogs & Cats: How to Protect Your Pets From a Closing Door and Other Garage Hazards

Introduction

For a lot of London families, the garage is part of the dog's daily routine. It is the way out to the car for a trip to the vet, the spot where muddy paws get wiped after a walk along the Thames Valley Parkway, and for many cats it is a favourite place to nap, explore, or slip out when nobody is looking. That makes the garage door one of the largest moving objects your pet meets every day, and most pets have no idea how heavy or fast it is.

The good news is that modern garage doors are designed with animals and small children in mind. A properly set up opener will stop and reverse when something is in the way, and a few simple habits remove almost all of the remaining risk. The bad news is that the safety features only work if they are installed correctly and tested, and the garage holds several other dangers for pets that have nothing to do with the door itself. This guide walks through how a closing door can hurt a pet, the safety systems that protect them, the monthly checks worth doing, the other garage hazards to watch for in an Ontario climate, the upgrades that help pet owners most, and realistic 2026 London prices.

How a Garage Door Can Hurt a Pet

A typical double steel door weighs well over a hundred pounds, and a heavy insulated or wood-look door can weigh a great deal more. The springs carry that weight while the door moves, but when it closes, it comes down with real force. Pets get hurt around garage doors in a handful of predictable ways.

Darting under a closing door

This is the classic accident. A dog hears the car, or sees you walking into the house, and bolts for the opening just as the door starts down. Cats are worse, because they tend to wait until the last moment and then shoot through the gap. A dog or cat that runs under a door is moving low to the floor, which is exactly why the height of the safety sensors matters so much (more on that below).

Lying or sleeping in the door's path

Many dogs like the cool concrete at the threshold in summer, or the sunny patch of driveway just outside the door. Cats will curl up against the bottom seal where the draught is smallest. A pet lying still in the opening while someone presses a remote from inside the car, or from a phone app across town, is the scenario the reversing system exists for.

Getting trapped in the garage

Pets slip into the garage unseen far more often than people realise, especially cats and small dogs. The door closes, everyone drives off, and the animal spends hours in a space that may be far too hot or too cold, with no water, and possibly with access to chemicals.

Paws, tails and the moving parts

Pinch points between door sections, the vertical tracks at the sides, and the bottom corner of the door are all places where a tail, paw or nose can be caught. Curious dogs sometimes chew the lift cables or the photo-eye wires where they run along the wall near the floor, which can damage the cable or disable the sensors.

Running out onto the street

An open garage door is an escape route. A dog that learns the door means "outside" may push past you the moment it starts to rise, straight toward a busy road.

The Safety Features That Protect Your Pets

Every automatic opener sold in North America since the early 1990s must include an external entrapment protection system, usually a pair of photo-eye sensors near the floor, as well as a built-in reversing feature that responds when the door meets resistance. Together, they are what stand between a pet and a closing door.

Photo-eye sensors and the six-inch rule

The photo-eyes are the two small boxes mounted on either side of the door opening near the floor. One sends an invisible beam across the opening and the other receives it. If anything breaks that beam while the door is closing, the opener stops and reverses the door.

Height is everything. The Door and Access Systems Manufacturers Association explains in Accidents Underscore the "Six-Inch Rule" that the sensors must be mounted no higher than six inches above the garage floor, because a beam set higher can miss someone lying or crawling underneath it. For a pet owner, that point is even sharper: a cat, a dachshund or a sleeping dog can be well under a beam that has been raised to a foot or more, often to stop a car bumper or a bin from triggering it. If your sensors are mounted high, have them lowered. Our photo-eye sensor guide explains alignment, cleaning and the most common reasons they stop working.

The auto-reverse (contact reversal) system

Separately from the photo-eyes, the opener watches how hard it is working as the door closes. If the door hits something and meets resistance, it should reverse. That backup only works if the force setting has not been turned up to overcome a stiff or badly balanced door. A door with tired springs forces the opener to work harder, and a technician or homeowner who turns up the force to "fix" that can leave a door that pushes down hard before it reverses. This is one of the most important reasons not to ignore a heavy or noisy door.

The wall control and remotes

DASMA's garage door opener safety tips recommend mounting the wall button at least five feet above the floor, out of reach of children, and watching the door until it is fully closed. Both matter for pets too. A large dog jumping up at the wall can bump a low button, and a door closed "blind" from inside a car can close on an animal that has wandered into the opening.

The Monthly Pet Safety Check

These checks take about five minutes, can all be done from the floor, and are the single most useful thing a pet owner can do. Put your pets inside the house before you start.

1. Look at the sensor height. Measure from the floor to the centre of each photo-eye. If it is more than six inches, book a visit to have them lowered.
2. Test the beam. Start closing the door and wave a broom handle or a box through the beam low to the ground. The door should stop and reverse right away.
3. Test the reverse on contact. Lay a roll of paper towel or a flat piece of wood on the floor in the middle of the opening and close the door. It should reverse as soon as it touches the object. If it presses down and stops, or keeps pushing, stop using the automatic close until it is fixed.
4. Check the sensor lights. Both sensors usually show a steady light when they are aligned. A flickering or dark light means dirt, misalignment or a damaged wire.
5. Inspect the wires along the wall. Look for chew marks, loose staples or a wire pulled away from the wall where a dog could reach it.
6. Check the balance. A door that feels heavy by hand, or will not stay put halfway, puts more strain on the opener and on its force settings.

Our monthly garage door safety test covers each of these in more detail, including what a failed result means.

Other Garage Dangers for Pets

The door is only part of the story. The garage is where most households keep the most toxic things they own, and in southwestern Ontario it swings between some of the hottest and coldest temperatures of any room connected to the house.

Antifreeze, ice melt and other chemicals

The ASPCA's article What Pet Dangers Are in Your Garage? lists antifreeze, ice melts, fertilizers, weed killers, rodent poisons, slug and snail baits and paints among the common hazards. Antifreeze is the one that worries vets most: it tastes sweet, a small amount can cause kidney failure, and a puddle under a car is easy to miss. Ice melt is a particular issue in a London winter, because it gets tracked into the garage on boots and tires and ends up on paws that are then licked clean. Store chemicals on high shelves or in closed cabinets, wipe up drips under the car, and rinse your pet's paws after walks on salted sidewalks. If you think your pet has swallowed something toxic, call your veterinarian or the nearest emergency animal hospital straight away rather than waiting for symptoms.

Summer heat

An attached garage with a dark, uninsulated door facing the afternoon sun can get uncomfortably hot on a humid July day. A pet shut in there, even for a short errand, can overheat quickly. Never use the garage as a place to leave a dog on a hot day, and never leave a pet in a parked car inside the garage. An insulated door keeps the space noticeably more stable, but it does not make a garage a safe kennel.

Winter cold

Most garages are not heated, and a January night in London can drop well below freezing. A cat that slips in unnoticed can be left in a very cold space for hours. If your garage is cold all winter, the door is usually the biggest reason; our guide to why your garage is so cold explains where the heat goes and what helps.

Exhaust fumes

Never run a car, generator or gas-powered equipment in a garage with a pet inside, even with the door open. Carbon monoxide builds up quickly in an enclosed space and animals are affected by it just as people are. Our carbon monoxide safety guide for attached garages covers detectors and safe habits.

Cats hiding in or under the car

In cold weather, cats, including neighbourhood strays, sometimes climb into a warm engine bay or sit behind a tire. Banging on the hood and checking around the tires before you start the car, and before you close the door, takes a few seconds.

Everyday Habits That Keep Pets Safe

• Watch the door all the way down. Do not press the remote and drive away. Wait until the door is fully closed.
• Put the dog inside first. When you arrive home, bring your pet into the house before closing the door, or close the door before letting the dog out of the car.
• Teach a "wait" at the garage. A dog that sits and waits while the door moves is a dog that is never under it.
• Do a head count before you leave. A quick check that the cat is inside prevents most accidental lock-ins.
• Keep the opening clear. Bowls, beds and toys should never live in the path of the door.
• Keep remotes out of reach. A remote left on a low table can be stepped on or chewed, and a door that opens by itself is an escape route.
• Never bypass the sensors. Taping the sensors together, or mounting them high to stop "false" reversals, removes the protection your pet needs most.

Upgrades Worth Considering for Pet Owners

A smart opener you can check from your phone

A Wi-Fi opener tells you whether the door is open or closed, sends an alert if it has been left open, and lets you close it from anywhere. For a dog owner who wonders "did I close the garage?" halfway to work, that peace of mind is the main benefit. Openers with a built-in camera go a step further, letting you see the floor of the garage before you close the door remotely, which is the safest way to close a door you cannot see. Our guide to garage door openers with built-in cameras explains how they work and whether they are worth it.

Careful use of an auto-close timer

A timer-to-close feature shuts the door automatically after a set delay, with a flashing light and a beep before it moves. It stops a door being left open all night, which is good for security and for keeping pets from wandering out. It also means the door moves when nobody is watching. If your pets use the garage unsupervised, leave the timer off, or choose a long delay and make sure the photo-eyes are mounted low and working perfectly. Our auto-close timer guide covers the safety rules built into the feature.

A pet door in the house wall, not the garage door

Pet flaps are sometimes cut into garage doors. We do not recommend it. Cutting a section weakens the panel and can void the door's warranty, the flap moves up and over with the door, it lets in cold air and pests, and it gives any animal (or a raccoon) a way in. If your pet needs access between the house and the garage, a flap in the interior house door or wall is the better choice, as long as the garage itself is safe to be in. Keep in mind that the door between a house and an attached garage often has fire-separation requirements, so check before cutting into it.

Tidy, protected sensor wiring

If you have a chewer, have the photo-eye wires run neatly along the wall and secured, or covered, so they are not a tempting target. A damaged wire can make the door refuse to close, or worse, fail to reverse if it has been badly spliced.

Realistic 2026 Costs in the London Area

Prices on this page are before HST.

Most pet safety fixes are small jobs. Typical 2026 figures for London and the surrounding area, all-in for a residential door:

• Opener safety sensors replaced and the reversing system tested: $125 to $250.
• Remote or keypad reprogrammed: $80 to $120.
• Yearly multi-point tune-up, including a force and reverse check: $120 to $220.
• Spring re-tension and re-balance, no new parts: $90 to $220.
• New belt-drive opener supplied and installed: $600 to $800.
• Chain or belt opener with a camera or battery backup, supplied and installed: $725 to $925.

Our service call is a flat $85, absorbed into the repair when we do the work. Lowering and realigning sensors that are simply mounted too high is often done during a tune-up visit. If a new door is on your list anyway, our price estimator shows real installed prices for London.

Common Mistakes Pet Owners Make

Raising the sensors to stop false reversals

It is tempting to move the photo-eyes up when a dog bed, a recycling bin or a bumper keeps breaking the beam. Move the obstruction instead. Sensors belong within six inches of the floor.

Turning up the force setting

A door that stops or reverses on its own usually has a balance, track or roller problem. Increasing the force hides the symptom and makes the reverse-on-contact less sensitive, which is the opposite of what a pet owner wants.

Closing the door remotely without looking

An app that closes the door from across town is only as safe as your view of the opening. If you cannot see the floor, use a camera, or wait until you are home.

Treating the garage as a kennel

Garages get very hot, very cold, and hold chemicals and exhaust. A short supervised stay while you wipe muddy paws is fine. Hours alone is not.

Frequently Asked Questions

Will my garage door stop if my dog or cat runs under it?

It should, if the photo-eye sensors are mounted low, aligned and working, and the reversing system is set correctly. Test both every month. A small or low animal can pass under sensors that are mounted too high without breaking the beam.

How high should garage door sensors be for pets?

No higher than six inches above the floor, which is the industry standard for everyone's safety. That height catches a crawling child or a small pet. Mounting them any higher to avoid false triggers defeats the purpose.

Is it safe to leave my dog in the garage?

Only briefly and under supervision. Ontario garages can overheat in summer and drop below freezing in winter, and they usually store chemicals such as antifreeze and ice melt. If you must keep a pet there for a short time, make sure the space is temperature-safe, has water, has no chemicals within reach, and that nobody will start a car inside.

Can I put a pet door in my garage door?

It is possible, but we advise against it. It weakens the panel, can affect the warranty, lets in cold air and pests, and moves with the door. A pet door in the house wall or interior door is a safer option, subject to any fire-separation rules for the door into an attached garage.

My cat keeps sneaking into the garage. What can I do?

Keep the interior door closed, do a quick check before you leave, and consider a Wi-Fi opener with a camera so you can look inside before closing the door from your phone. Sealing gaps around the door also stops a cat getting in, and keeps wildlife out; see our guide to keeping pests out of your garage.

My dog chewed the sensor wire and now the door will not close. Is that dangerous?

The door refusing to close is the system doing its job: with no sensor signal, most openers will not close on a normal press. Do not bypass it by holding the button down as a routine. Have the wire repaired or the sensors replaced, then test the reverse before using the door normally.

Are older garage doors riskier for pets?

Openers made before the early 1990s may have no photo-eyes at all, and older doors are more likely to be out of balance. If your opener has no sensors near the floor, replacing it is the most important pet safety upgrade you can make.

Conclusion

Your dog or cat cannot understand a garage door, so the door has to be set up to understand them. Low, aligned photo-eye sensors, a properly balanced door with sensible force settings, a monthly five-minute test, and a few simple habits such as watching the door close and counting pets before you leave remove nearly all of the risk. Add safe storage for chemicals, a garage that is never used as a hot or freezing kennel, and perhaps a smart opener you can check from your phone, and the garage becomes just another safe part of your pet's day.

If you would like a London-based technician to check your sensor height, test the reversing system, balance the door and talk through the right upgrades for a household with pets, call 519-619-7901 or send us a note through our contact page. AA Advantage Doors has been keeping London-area families, and their four-legged members, safe since 2009.