How to Install a Channel Drain
Install a durable trench channel drain to collect and redirect surface runoff away from driveways, patios, and foundations using proper slope and concrete bedding.
- Read the tools, materials, safety notes, and steps below for free.
- Tap Start Camera Coach when you want hands-free voice help.
- Allow camera and microphone. Point your phone at the work; the coach watches your progress and tells you the next step.
🧰 Required Tools & Equipment
- ✓ Trenching shovel
- ✓ Mason line and stakes
- ✓ Line level or 4-foot spirit level
- ✓ Rubber mallet
- ✓ Margin trowel
- ✓ Wheelbarrow or concrete mixing tub
- ✓ Hacksaw or PVC pipe cutter
📦 Materials & Supplies
- ✓ Channel drain sections with grates
- ✓ End caps and bottom outlet adapter
- ✓ 4-inch PVC or corrugated drain pipe
- ✓ PVC primer and cement
- ✓ Fast-setting concrete or sand mix
- ✓ Crushed stone base gravel
- ✓ Duct tape
⚠️ Safety Checkpoints & Warnings
- • Call 811 to locate buried utilities before digging any trenches.
- • Wear heavy work gloves and safety glasses when cutting PVC and handling dry concrete mix.
- • Wear a dust mask or respirator when pouring and mixing dry concrete powder.
📋 Step-by-Step Guide (6 Steps)
Establish the Slope and Layout
Drive stakes at the start and discharge ends of the intended trench line. Tie mason line tightly between the stakes, setting a downward slope of at least 1/8 to 1/4 inch per linear foot toward the discharge location. Use a line level to verify continuous fall along the entire run.
- • A taut string line runs directly above the target drainage path.
- • The string line slopes consistently downward toward the drainage outlet.
- • Setting the string level instead of pitching it downward, causing standing water.
Excavate the Trench
Dig a trench along the string line that is 4 inches wider and 2 inches deeper than the channel drain body. Clear loose soil from the bottom and tamp the trench base flat. Verify trench depth continuously with a tape measure referenced against the string line.
- • A flat-bottomed trench with straight vertical sidewalls along the string line.
- • Uniform 2-inch clearance below the channel drain height across the entire length.
- • Digging too narrow, preventing adequate concrete support along the sides of the channel.
Assemble Channel Sections and Outlets
Click the channel drain sections together using the built-in interlocking tabs. Install an end cap on the upstream end and attach the outlet adapter on the downstream end. Cover the grates with duct tape to keep wet concrete and debris out of the drainage channel during installation.
- • Fully connected, continuous channel drain assembly with sealed end caps.
- • Grates completely sealed with a protective layer of duct tape.
- • Leaving the top grates off during installation, which allows the plastic channels to warp under concrete pressure.
Lay Concrete Bedding and Set the Channel
Mix concrete to a stiff, peanut-butter consistency and spread a 2-inch-thick bed along the bottom of the trench. Lower the assembled channel into the wet concrete, pressing down gently until the top of the grate sits 1/8 inch below the string line. Tap lightly with a rubber mallet to bed it evenly.
- • Channel drain rests firmly in concrete bed parallel to the string line.
- • Top edge of the grate is consistently 1/8 inch below the guide string.
- • Using concrete that is too watery, causing the channel drain to float or shift out of level.
Connect the Discharge Pipe
Apply PVC primer and cement to the drain outlet adapter and slide the 4-inch PVC discharge pipe into place. Route the discharge pipe with a continuous downward slope to daylight, a dry well, or a pop-up emitter. Support the pipe underneath with compacted soil or gravel so it does not pull down on the channel joint.
- • Discharge pipe fully seated into the drain outlet adapter.
- • Discharge pipe runs continuously downhill without dips or bellies.
- • Forgetting to glue the PVC outlet joint, risking soil infiltration and joint separation over time.
Pour Concrete Haunching and Finish Edge
Pour concrete into the gaps along both sides of the channel drain, filling up to the surrounding grade. Use a margin trowel to consolidate the concrete, eliminating air voids, and tool the surface with a slight outward slope away from adjacent pavers or asphalt. Allow to cure for 24 hours before removing tape and running heavy traffic over it.
- • Concrete flush with surrounding pavement on both sides of the drain.
- • Clean, tooled concrete surface with the tape-protected grates still sealed.
- • Leaving air pockets under the channel shoulders, creating weak points that can crack under vehicle weight.
Credit: inspired by an original tutorial by This Old House — watch the original on YouTube.
Don’t have everything?
- No Trenching shovel? Standard flat spade shovel
- No Line level? 4-foot spirit level set directly on the channel grate segments
- No Solid PVC drain pipe? Heavy-duty corrugated non-perforated drain pipe with snap adapter