Retaining Walls In Springvale

Treated pine sleepers between timber or galvanised posts are the cheapest built option, averaging $250 to $450 per square metre of wall face. Below about 500 millimetres, a rock or boulder edge can be cheaper again, though it is really garden edging rather than structural retaining. The catch with the cheapest option is lifespan - pine in wet clay realistically gives you 15 to 20 years, where concrete sleepers will outlast the house. If the budget is the constraint, terracing two low pine walls often beats one taller one on both cost and appearance. Every job is unique, so we confirm the figure in writing after measuring.

It depends on height, because walls are priced by the square metre of face rather than by length. A 10 metre wall at 600 millimetres high is 6 square metres, so on average $1,500 to $2,700 in pine or $2,400 to $4,200 in concrete sleepers. The same 10 metre wall at 1.2 metres high is 12 square metres, so $4,800 to $8,400 in concrete sleepers, plus an average of $1,500 to $3,500 for engineering and a permit because it is over a metre. Excavation access and whether there is a surcharge load above the wall shift the number as well. Every job is unique, which is why we measure on site and give you the figure in writing.

Generally yes once the wall exceeds one metre in height, under the Building Regulations 2018. You can also need one below that height if the wall retains a surcharge load, such as a driveway, a pool or a neighbouring building sitting above it. A permit means an engineer designs the wall and computations are submitted, which adds cost and a few weeks to the timeline. We check this before quoting and tell you exactly what applies, because an unpermitted structural wall is a problem that resurfaces at sale time.

A straightforward 10 to 15 metre sleeper wall on a site a machine can reach is usually three to five days, including excavation, footings, drainage and backfill. Footing concrete needs time to cure before the wall is loaded, so we do not rush that stage. Hand excavation on a tight block, rock in the subsoil, or a wall that has to be built in sections around existing trees can double the time on site. If a permit is required, allow several weeks before we start for the engineering and council approval.

Water is the answer in most cases. Saturated soil behind a wall weighs far more and pushes far harder than damp soil, and reactive clay across the south-east swells when it is wet, so the load on the wall changes with the seasons. Walls fail when the drainage layer was skipped, when the excavated clay was pushed back in as backfill, or when the agi drain was not wrapped and silted up within a couple of winters. We build the drainage as a system - free-draining backfill, a wrapped agi drain at the base falling to a legal discharge point, and footings deep enough for the height. That is the unglamorous part of the quote and it is the part that decides whether the wall is still straight in fifteen years.

It depends on who benefits from the retaining and on any agreement between the two owners, so it is genuinely worth sorting out before the job rather than after. In broad terms, the owner who caused the change in ground level is usually the one responsible for retaining it. Where both properties benefit, neighbours often share the cost, and having that conversation early avoids a dispute once the excavator is on site. We can build to a boundary and will point out where the levels suggest shared benefit, but the legal position between you and your neighbour is one to settle between yourselves or with your council before we start.