Door-line surface drainage
If the drain is catching exterior runoff at the garage opening and tying into existing private drainage, there usually is not a separate permit for the drain itself.
RESIDENTIAL · GARAGES
Garage Trench Drain Installation in Toronto & the GTA
Garage trench drains stop snowmelt, wash water, and driveway runoff at the threshold before it crosses the slab. We set the drain at the low point, tie it into legal drainage, and finish the edge clean.
The problem
Why garages need trench drains
A garage opening is one of the easiest places for surface water to get inside. Once water starts crossing the threshold, it brings salt, grit, and freeze-thaw damage with it.
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Water crossing the door line
Runoff from the apron gets past the weather seal and ends up on the garage floor. The problem is worse on driveways that slope back toward the house.
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Salt and rust on the slab
Snowmelt from vehicles carries road salt into the garage. Over time that eats at fasteners, stains concrete, and shortens the life of the door hardware.
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Ice at the garage entrance
Meltwater that sits at the threshold refreezes overnight. That creates a slip point outside and a sticking point at the bottom of the overhead door.
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Persistent damp floor
If the slab stays wet, anything stored at floor level pays for it first. Cardboard, trim, drywall offcuts, and tool cases all absorb moisture fast.
What we install
Built for garages specifically
Garage drains need to handle repeated vehicle traffic, winter salt, and the movement that happens right at the entry slab. We usually keep the profile compact, but we do not undersize the grate.
- LOADClass A / B, step up to C for heavier service traffic
- WIDTH100 - 150 mm
- MATERIALPolymer concrete or HDPE channel body
- GRATEGalvanized steel, ductile iron, or stainless where exposure is high
Door-line drains live in one of the harshest spots on the property. Salt, freeze-thaw, and tire traffic all hit the same joint, so clean installation and a solid patch matter as much as the drain body.
Placement
Where the drain goes in a garage install
Most garage drains sit right at the door line or just outside the apron where runoff first concentrates.
For most homes, we install the drain across the full garage opening, right where surface water would otherwise cross the threshold. That catches driveway runoff, snowmelt off vehicles, and wash water before it reaches the slab.
If the garage floor itself is the low point, we confirm whether the problem is exterior runoff, interior wash water, or both. Then we tie the drain into drainage that can legally take it instead of cutting first and guessing later.
- Existing private storm drainage
- Sump or catch basin connection where viable
- Interior plumbing tie-in only where approved and appropriate
Install Day
What a garage trench drain install looks like
A standard door-line garage drain is usually a one-day job on site. Interior slab work or more involved tie-ins can extend that to a second day, but the sequence stays the same: cut, excavate, set, tie in, patch.
- Typical site time1 day
- WalkableSame day
- Vehicles back on24-48 hr cure
- 01
Lay out the door line
We mark the exact cut so the drain lands square to the opening and stays flush with the finished slab or apron.
- 02
Saw cut and remove the channel
The crew cuts clean edges, lifts out the strip, and checks what is actually under the slab before setting final depth.
- 03
Prepare the bed and slope
We compact the base, dry-fit the body, and confirm the run has enough fall to move water out instead of holding it.
- 04
Make the drainage tie-in
The outlet is tied into the approved drainage route and tested before we pour back around the channel.
- 05
Patch and finish the edge
Concrete or asphalt is repaired tight to the frame so tires cross cleanly and the door seal meets a finished surface.
Code and Tie-ins
Garage discharge: what's legal, what isn't
Garage drains look simple from the surface, but the discharge side decides whether the job is straightforward or permit-driven. We sort that out before cutting the slab.
Interior plumbing tie-ins
If the job involves cutting inside the garage and tying into building plumbing, permit and code requirements depend on the use, the discharge type, and the existing system.
Legal discharge matters
We do not guess at where garage water should go. Surface runoff, wash water, and plumbing drainage are not all treated the same, and they should not be tied together casually.
Typical cost
Fixed quote after site visit
Garage drain pricing depends on whether the cut is at the door line or inside the slab, and what the legal discharge route looks like.
What changes the price
- Length of the garage opening or interior run
- Concrete thickness and how cleanly the slab can be opened
- Drainage route - existing private line vs. new tie-in work
- Grate material and load class
- Whether the work is exterior only or involves interior plumbing
Get a fixed-price quote after a free site visit — not a range.
FAQ
Common questions about garages
Should the drain go inside the garage or outside the door?
Usually at the door line or just outside it. That catches water before it crosses the threshold. If the garage slab itself is sloped to an interior low point, we review that separately and confirm what kind of drainage connection is legal.
Will this stop snowmelt from my car from spreading across the floor?
Yes, if the drain is placed where the water actually collects. A door-line trench drain keeps most meltwater from getting deep into the slab area, which makes winter cleanup much easier.
Is it possible to retrofit a drain into a finished garage slab?
Yes. Most of our garage drain work is retrofit work in existing concrete. We saw cut the strip, excavate, set the channel, tie in the outlet, and patch the slab back around it.
Will the grate handle the cars and SUVs I park in there?
Yes. We size the grate for the traffic actually using the garage. Passenger vehicles are one thing; service bays, commercial vans, and heavier vehicles need a stronger grate and sometimes a wider body.
Do I need a permit for a garage trench drain?
Sometimes, but not always. Exterior door-line drains tying into existing private drainage are usually straightforward. Interior plumbing tie-ins or municipal connection work may require permits and inspection.
Where do garage drain installs usually go wrong?
Putting the drain where it looks neat instead of where water actually runs. The second mistake is tying it into the wrong system. We see both problems often on DIY and handyman installs.
Licensed & insured · Serving the GTA since 1991
Installed by TroughDrain.ca, a division of MT Drains & Plumbing Ltd.
- Master Plumber Licence #T95-5349719
- Plumbing Contractor #T94-5214638
- Building Renovator #T85-4544391
More applications
Other residential work we do
Driveways & Laneways
Linear surface drainage designed for long runoff paths, sloped driveways, and vehicle traffic.
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Patios, Walkways & Hardscapes
Low-profile surface drainage designed to protect finished outdoor spaces without altering elevations.
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Pool Decks & Recreation Areas
Low-profile drainage designed to manage splash water and seasonal moisture without disrupting recreation spaces.
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