Signs your timber wall needs replacing
- ✓The wall is leaning forward or bowing in the middle
- ✓Sleepers are soft, cracked or crumbling at ground level
- ✓Posts are rotted or moving when you push them
- ✓Soil is washing out through gaps
- ✓The neighbour’s fence on top is starting to tilt
Demolition without damaging the neighbours’ fence
Removing a failing boundary wall has to be done in stages so the soil behind it doesn’t slump. Builders typically support the bank, pull the old sleepers and posts, remove the spoil, then install the new posts and drainage before backfilling.
What to replace it with
Most people replace failed timber with concrete sleepers, which don’t rot and aren’t eaten by termites. Sandstone and block walls are other options. See concrete sleeper retaining walls or block retaining walls.
Drainage and approvals
Every retaining wall needs a way for water to escape: slotted 100 mm ag-pipe in a geofabric sock, bedded in washed 20 mm aggregate, relieves water pressure behind the wall. Walls over the NSW exempt height (generally 600 mm, and at least 1 m from a boundary), or walls supporting a structure, need structural engineering and CDC/DA approval. More on retaining walls in Wollondilly.
Frequently Asked Questions
Can I just replace the rotten sleepers?+
Sometimes, if the posts are sound and the wall is still plumb. If the posts are rotted or the wall is leaning, a full rebuild is usually the safer option.
Is my block bushfire prone?+
Large parts of Wollondilly are mapped as bushfire prone land. If yours is, ask your builder whether a timber wall is appropriate or whether concrete, block or sandstone is a better choice.
How Wollondilly Wall Co works
Wollondilly Wall Co is a local lead-matching service connecting Wollondilly property owners with independent, licensed structural landscapers and retaining wall contractors. When you call or send a request, we pass your details to a local builder who contacts you to arrange a site measure and quote. The builder you’re matched with is responsible for the work, its pricing and any warranties.