Retaining walls are one of those features most homeowners don’t think about until they need one. Whether you’re dealing with a sloped yard, preventing soil erosion, or adding dimension to a flat landscape, a well-built retaining wall solves real problems while adding visual appeal.
When Do You Need a Retaining Wall?
- Sloped yards: A retaining wall creates usable flat space and prevents water from pooling near the house
- Erosion control: Ottawa’s spring runoff moves serious soil. A retaining wall stops that migration
- Tiered landscaping: Raised garden beds, multi-level patios, and defined planting zones all need structural support
- Driveway and walkway edges: Where hardscape meets a grade change, a wall holds everything in place
Do You Need a Permit in Ottawa?
The City of Ottawa generally requires a building permit for retaining walls exceeding 1 metre (about 3.3 feet) in height. Walls under that height typically don’t need a permit, but exceptions exist for walls near property lines, walls supporting loads above them, or stepped walls that collectively retain more than 1 metre. Always confirm with the city before starting. For more on permits, see our guide on simplifying backyard project permits.
Drainage: The Hidden Key
The most common reason retaining walls fail in Ottawa is poor drainage behind the wall. Water pressure building up behind a wall is the force that eventually pushes it out of alignment. Proper drainage means clear gravel behind and below the wall, a perforated drainage pipe at the base directing water away, and geotextile fabric preventing soil from migrating into the drainage layer. In Ottawa’s climate, this is non-negotiable.
Retaining Walls as Design Features
- Seating walls: At 18-20 inches high around a patio or fire pit, they double as casual seating
- Raised garden beds: Stone-faced planters with better soil than Ottawa’s native clay
- Multi-level outdoor spaces: An upper patio stepping down to a lower fire pit area
- Driveway borders: A low wall adds definition and keeps soil off the interlock surface
Visit our project portfolio to see retaining walls integrated into Ottawa outdoor living projects.
Get Your Free Estimate Today
Need a retaining wall for your Ottawa property? Contact JAL Deck & Interlock for a free estimate. We serve Ottawa and surrounding areas including Stittsville, Carleton Place, Nepean, Barrhaven, and beyond.