What can stay in the garage over winter: gasoline, batteries, paint and lawn chemicals

Garage storage over winter in the GTA is mostly a question of what survives the cold, but three items carry a rule rather than a preference: the gasoline, the propane cylinder and the running engine. Ontario's Fire Code sets a litre limit for fuel in an attached garage, Ontario's fuels regulator keeps propane out of every structure, and the same Fire Code decides where carbon monoxide alarms go in a house with a garage. Late September is the week to sort it, because the mower is about to be put away and the snowblower is about to come forward.

How much gasoline may be kept in an attached garage in Ontario?

No more than 50 litres of flammable and combustible liquids in total, and of that, no more than 30 litres of Class I liquids. That is Article 4.2.4.6 of the Ontario Fire Code (O. Reg. 213/07), which applies to a garage or shed attached to a dwelling unit. Gasoline falls in Class I: the Code makes every flammable liquid, meaning a flash point below 37.8 °C, a Class I liquid, and CCOHS's chemical profile of gasoline notes it can ignite at room temperature.

The limits tighten as the fuel moves closer to where people live. Inside the house itself the Code allows 30 litres in total, of which only 10 litres may be Class I. On an exterior balcony the answer is none at all.

Article 4.2.4.6 is written for attached garages and sheds. Windsor Fire & Rescue Services, an Ontario fire department, calls a detached garage or shed the safest place for gasoline, away from pilot lights, electric motors, heaters and stoves, and away from paper, rags and cardboard. If the house has a detached shed, that is where the fuel can goes.

What counts toward the 50 litres, and what container is allowed?

Everything flammable or combustible in liquid form counts, not only the gasoline. The Code requires such containers to be marked with a warning that the contents are flammable and should be kept away from heat, sparks and open flames, or to carry the equivalent labelling under federal product law, so the label is the fastest way to sort the shelf. Stand each can in one of two groups — flammable or combustible — and add up the capacities printed on them.

• The container itself has a standard. Article 4.2.3.1 requires containers for these liquids to be built to one of the listed standards, including CSA B376, Portable Containers for Gasoline and Other Petroleum Fuels, or ULC safety-container standards. Windsor Fire puts it plainly: use only a ULC- or CSA-approved plastic or metal gasoline container, and never glass jars.
• The one exception is small. Article 4.2.3.3 allows a non-conforming container for a Class I liquid only up to 1 litre. A 4-litre juice jug of mower gas does not qualify.
• Leave room for expansion. Windsor Fire says to fill a container no more than 90 to 95 per cent full; CCOHS says to leave 5 per cent of the space. Check that the cap and the vent cap both seal.
• Keep the amount to what the season needs. Both CCOHS and Windsor Fire tell you to store only the minimum amount of gasoline.

Can e-bike and tool batteries stay in an unheated garage?

No. Toronto Fire Services' instruction is to store lithium-ion batteries at room temperature and away from anything that can catch fire, and an uninsulated garage in January is well below room temperature. That covers e-bike and e-scooter packs, cordless drill and trimmer batteries, and the battery for an electric mower or leaf blower.

Bring them indoors to a spot away from anything flammable, and follow the manufacturer's storage instructions for charge level. When you charge one before spring, Toronto Fire says to keep it in sight, unplug it when charging is complete, and never charge on a soft surface such as a bed or couch. If a pack shows an odour, a change in colour or shape, too much heat, leaking or odd noises, stop using it; a battery that is sparking or smoking is a 911 call.

Paint, lawn fertilizer and pesticides: when the label decides

For these, the product label is the rule. Read the storage statement on each container before the first frost. If it says to protect from freezing or to store above a stated temperature, the unheated garage is out and the product goes to a basement shelf or utility room.

• Pesticides, including weed-and-feed products: Health Canada's instruction is to keep unused product in a secure location out of the reach of children and pets, and never in anything but the original container. A locked cabinet satisfies the first part wherever it stands.
• Paint and stain you want to recycle later: Product Care, which runs Ontario's free paint recycling network, only takes paint in its original container, tightly sealed with the label on, and refuses containers that are badly rusted, leaking or bulging. A can that sits on a damp garage floor for years and rusts through becomes unrecyclable, so keep paint off the concrete and on a shelf.
• Anything that has lost its label: Product Care also refuses unidentifiable and unlabelled containers. If you cannot tell what is inside, deal with it this autumn while you still remember.

Running the mower or snowblower in the garage: the carbon monoxide rule

Do not start or idle an engine inside the garage, even for a minute to warm it up. Health Canada lists lawn mowers, snowblowers, generators and vehicles as carbon monoxide sources, names garages and sheds among the places where using them exposes people to dangerous levels, and notes that indoor exposure risk is greatest in fall and winter. Push the machine out onto the driveway first, then pull the cord.

The Fire Code backs this up with hardware. Section 2.16 applies to every residential building that contains a storage garage, and requires a carbon monoxide alarm adjacent to each sleeping area of a suite that shares a common wall or floor/ceiling assembly with that garage. The section does not apply where the alarms were installed in accordance with the Building Code as it read on or after 1 January 2025. If the bedroom above the garage has no CO alarm, that is the purchase to make before the snowblower's first run.

The order for a garage clean-out this weekend

1. 1Pull everything liquid onto the drivewayFuel cans, paint, stain, thinner, lawn and garden products, pool chemicals, washer fluid. Do it on a dry day with no ignition sources nearby and nobody smoking.
2. 2Sort by label, not by memoryFlammable, combustible, pesticide (look for a P.C.P. registration number), water-based paint, and unknown. Add up the flammable and combustible litres against the 50 L and 30 L limits.
3. 3Move the propane cylinder outside for goodUpright, valve closed, on a hard surface where it will not be knocked over.
4. 4Bring in the batteries and anything that must not freezeLithium-ion packs and any product whose label asks for protection from freezing go indoors, away from heat sources and anything that can catch fire.
5. 5Swap the machinesFollow the mower manual's storage section for the fuel left in the tank, park the mower at the back, and put the snowblower and shovels nearest the door. Add fuel outdoors only.
6. 6Get the discards off the propertyDamaged batteries, unlabelled containers and old fuel go to a household hazardous waste depot, not the curb.

Where the things you are not keeping should go

Old gasoline, solvents, unwanted pesticides and propane cylinders go to your region's household hazardous waste depot, not the curb: free for residents at Halton's depot and Peel's Community Recycling Centres, and in Toronto at a Drop-Off Depot or through a free Toxic Taxi pickup. Our post on what movers will not take covers the daily limits and how the containers should travel. Toronto classes lithium-ion batteries as household hazardous waste too. Leftover paint in its original, sealed, labelled can can go to any Product Care paint drop-off instead, including some retail stores.

For lithium-ion batteries on the way to a depot, Toronto Fire's instruction is to put each one in a clear plastic bag or cover the terminals with clear packing tape, duct tape or electrical tape, and to drop damaged batteries off immediately rather than storing them. Never pour gasoline onto the ground or into a street drain — see our post on where wash water may go for how the storm sewer by-laws treat anything other than rain.

Is a garage clean-out worth hiring out?

Usually not. It takes a tape measure, a marker and one trip to the depot, and the decisions about what to keep are ones only the owner can make. What it does change is the rest of the winter: once the snowblower is at the door and the fuel is where the Code allows it, the next job is the driveway. If you would rather that job were someone else's, our snow removal service covers Oakville, Mississauga, Milton, Burlington and Etobicoke, and lawn mowing covers the cuts left before the mower goes to the back of the garage.