Excavation & Drainage
Excavation, site prep and drainage.
The work behind the wall. Cutting the wall line, preparing footings, and making sure water has somewhere to go.
Excavation and site preparation
Some sites need excavation before the wall can be properly rebuilt — cutting a bench along the wall line, digging footings to depth, or removing failed backfill and old material.
On sloping Wollongong blocks, access decides a lot. What we can get into the yard changes the method, the time and the price.
- Cutting and benching the wall line
- Footing and post hole excavation
- Removing old walls and failed fill
- Spoil loading and disposal
- Levelling behind the completed wall
- Working around services and boundaries
The water has to go somewhere
Retaining walls hold back soil, but they also have to deal with water moving through that soil. Saturated ground is far heavier than dry ground, and that extra pressure is what pushes walls over.
There's no single spec that suits every wall. What we install depends on the height, the material, what's behind the wall and where the water can actually be discharged.
What a drainage system usually involves
- A free-draining aggregate layer behind the wall
- Ag pipe laid to fall where appropriate
- Geotextile to stop fines migrating
- Outlets that discharge somewhere sensible
- Managing surface and roof water above
- Keeping drainage paths clear over time
Surface water above the wall
Roof water, driveway runoff and overland flow above the wall often matter more than what's directly behind it. If water is being funnelled at the top of the wall, no amount of aggregate behind it fixes the underlying problem.
Send through a couple of photos and we'll get a better idea of the site.
Call us, or use the quote form. Photos of the wall, the ground behind it and the access tell us more than a description ever will.
More
Other retaining wall work
Retaining Wall Construction
New retaining walls for residential sites across Wollongong and the Illawarra.
Concrete Sleeper Walls
Concrete sleeper systems with galvanised posts, where the site suits them.
Timber Sleeper Walls
Timber systems for garden and lower-level retaining where appropriate.
Block Retaining Walls
Masonry and segmental block systems for the right applications.
Retaining Wall Replacement
Removing and replacing failed, leaning or deteriorated walls.
Retaining Wall Repairs
Repairs only where repair is genuinely the right call.
Retaining Wall Costs
What actually moves the price on a Wollongong retaining wall.