Underpinning near a boundary in Melbourne: the adjoining owner gets 14 days before work can start

What counts as protection work

The Building Act 1993 defines protection work to include "underpinning, including the provision of vertical support, lateral support, protection against variation in earth pressures, provision of ground anchors and other support for adjoining property." That definition is about work that supports the NEIGHBOUR's property, not a statement that every underpinning job at your own house is protection work.

The trigger is a decision, not a rule of thumb: the Building Regulations 2018 say protection work must be provided "if the relevant building surveyor determines that protection work is required," and the surveyor makes that call at the permit stage, having regard to things like excavation depth and the risk of damage to the property next door. Nothing published says underpinning near a boundary always needs it — only that it can, and that the surveyor is the one who decides.

The notice, and the 14 days

Where protection work is required, the Act says the owner "must, before commencing the building work, serve on the owner of the adjoining property and the relevant building surveyor notice of the proposed building work." That notice goes out before anything starts, not after.

From there, the adjoining owner has 14 days to respond, and the Act treats silence as consent: an owner "who fails to give a notice ... within the required time is taken to have agreed to the proposed protection work." Either way, the Act is clear that no work covered by that requirement may begin "until" agreement, deemed agreement, or a determination is in place — so the 14 days is a floor on the schedule, not paperwork to file after the fact.

Where this shows up in practice

Reservoir is one of the suburbs we cover where this is worth planning for early. Darebin's Heritage Overlay lists three heritage precincts and, on our count, twelve individually listed houses in Reservoir, and older housing on that kind of block is more often built close to the boundary than a modern estate lot is. A footing problem on one of those houses can turn into a boundary conversation the moment the surveyor looks at how close the work sits to next door.

None of this changes what causes a footing to move — that is a separate question, and we have not found a published statement about Reservoir's ground specifically. It changes the schedule: a job that also needs a protection-work notice cannot start until that 14-day clock has run, or the neighbour has agreed sooner.

What to ask before a start date is set

Ask whether the surveyor has determined protection work is required, and if so, ask to see the notice served on the adjoining owner and when it was served — the 14 days runs from service, not from the permit application. If the notice was served properly and 14 days have passed with no response, the Act treats that as agreement, and a start date can be set. If it has not been served yet, that is not a delay in the work; it is a step the Act puts before the work.