0405 950 053 08 7225 6514 Office Suite 4, Wellington Business Centre, 2 Portrush Rd, Payneham, SA 5070
0405 950 053 08 7225 6514 Office Suite 4, Wellington Business Centre, 2 Portrush Rd, Payneham, SA 5070

A retaining wall on the boundary of two properties. Who’s responsible?

Retaining walls have long been the cause of neighbours’ feuds. Take it from a construction company that’s worked on thousands of Adelaide homes. Erected to hold soil to a slope that wouldn’t naturally hold it, a retaining wall doubles as a fence foot. The wall itself isn’t considered to be a fence and is covered by different laws. In other words, it’s confusing, frustrating and feud-starting.

Before any preparation work for retaining wall begins, you need to know if a development approval (or DA) is required and whether the neighbour needs to be informed.

This applies to homeowners on both sides of the wall – whether it’s being constructed, demolished, repaired or altered. Local council usually acts as the ‘mediator’ and approval is necessary.

However, if the wall retains a difference in ground level of one metre (or less), approval isn’t required.

The overall difference in ground level must be measured. It comes as no surprise, if the retaining wall affects the stability of the neighbour’s land, the homeowner planning to carry out work must provide notice of works. Yes, even if the development approval isn’t a must.

Stability is deemed affected if:

  1. It comes within 600mm of the boundary, unless it’s 200mm or less in height and for landscaping purposes, and
  2. If an excavation which intersects a notional plane extending downwards at a slope of 1 vertical to 2 horizontal, forms a point 700 mm below natural ground level at a boundary with an adjoining site.

And what is considered ‘notice’ in this situation?

The intention to perform work and the nature of it, 28 days prior. This is extremely important and if failed to fulfill these requirements, risks a fine of up to $10,000. If this all feels overwhelming, it’s worthwhile investing in expert construction services in Adelaide.

What if the neighbour objects the works?

We’re glad you asked. If there are concerns, a homeowner can bring a structural engineer in to prepare a report – for excavations, underpinning, stabilisation or foundation strengthening. The neighbour proposing the work must follow and comply with the engineer’s advice.

However, the neighbour with the plans can request payment from the homeowner if they require work to be carried out, as specified, by an engineer.

And who’s actually responsible for erecting the wall?

It depends, on the natural state of the land.

When the land is altered, it requires support of a retaining wall. The party who alters it also has the obligation to create the wall. It makes no sense for both landowners to build separate retaining walls. Hence, why it’s more practical for one wall, led by the person making the changes.

And what about the cost? The neighbour who built the wall is also responsible for the repair and maintenance. If the structure was built to benefit both parties, upkeep is a shared responsibility. Structural engineers are worthwhile investing in to keep the peace between your two Adelaide homes and maintain construction productivity.

At Solution for Construction, we understand the difficulties that arise when two properties share land. Whichever side of the fence you sit on, our team of structural engineers can offer advice, support, and full reports. Start the process by booking a free 20-minute consultation with Naveesh, a leading structural engineer consultant in Adelaide.

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Dream Maker;Problem Solver

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