Retaining Walls near you

The material sets the look, the construction method and how easily the wall can be repaired later. What decides its lifespan is whether it is built as a complete system suited to its height and to the load behind it, because each material comes with its own way of handling footing, drainage and setback.

Water is what brings retaining walls down. Saturated soil is much heavier than dry soil, and when it freezes it expands against the back of the wall. A well-built wall gives that water a way out: a zone of clean crushed stone directly behind the face, a perforated drain pipe at the base that carries water to a safe outlet, and filter fabric that keeps fine soil from clogging the stone.

Taller walls and walls with a load above them are usually reinforced with geogrid, a flat polymer mesh laid between courses and extending back into compacted backfill. The grid ties the face to a mass of reinforced soil so the two act as one. Its length, number of layers and spacing depend on the block system, the soil and the wall's height, so they should come from the manufacturer's design tables or an engineer, never from guesswork.

Permit rules for retaining walls are set locally and usually hinge on height, location and what the wall supports. In Toronto, the City's building permit guide requires a permit for a retaining wall more than one metre high that is on or next to public property, next to a building entrance, or on private property the public can access. Elsewhere, ask your municipality or borough before the design is settled. A wall that holds up a driveway, a slope, a pool or a structure calls for an engineer's design, and the civil engineering page explains what that involves.

Property lines deserve the same care. A wall built on the wrong side of the line, or one whose footing, drain outlet or reinforcing grid crosses it, can turn into a dispute when either house is sold. Check the line on an existing survey or certificate of location, or have a land surveyor stake it, and talk to your neighbour before work starts, especially if their soil, fence or trees will be disturbed or if water from the drain could end up on their side.

When wet soil freezes, it expands and can lift or shove whatever it grips, then settle back unevenly in spring. A retaining wall meets that force from two directions: heaving under its base and ice forming in saturated backfill behind it. The defences are the ones drainage already provides: a well-compacted, free-draining base set partly below grade, clean stone behind the wall that doesn't hold water, and grading above the wall that keeps runoff and snowmelt from pouring down its back.

Winter habits matter too. Snow piled on top of or against a wall melts straight into the backfill in spring, and heavy equipment driving along the top adds weight the wall may not have been designed to carry. Show your snow removal contractor where the wall is and keep large snowbanks back from its top edge.

Movement that grows from one season to the next means the wall is losing ground. Keep people and vehicles away from the area above and below a wall that is actively moving, and have it assessed promptly if it stands beside a walkway, a driveway or a neighbour's yard.

A local problem often has a local repair: loose caps glued back down, a short section of block wall taken apart and reset after its base is corrected, a blocked drain outlet cleared, or the grade above the wall reshaped so runoff stops soaking the backfill. Segmental block walls lend themselves to this because the units can be removed and reused.

When the whole wall leans or bulges, the cause is usually buried: no drainage, a base that was never compacted, or a wall built taller than its design allowed. Rebuilding means removing the wall and the saturated backfill, correcting the base, drainage and reinforcement, then building again, often with the sound blocks or stone. Any repair on a tall wall, or on one that holds up a driveway or a structure, should be reviewed by an engineer.