Building in a Flood Zone: What Maitland and Hunter Owners Need to Know

Large parts of Maitland, Raymond Terrace and the lower Hunter floodplain carry a flood overlay. It does not stop you building, but it changes what you can build and how.

Flood planning level

The key number is the flood planning level, usually the 1% annual exceedance probability flood level plus a freeboard allowance, commonly 500mm. Council will tell you the figure for your specific lot in a planning certificate.

Habitable floor levels generally have to sit at or above that level. That single requirement drives most of what follows.

What it means in practice

Your floor may need to be higher. On a low lot this can mean a suspended floor, additional fill, or a raised slab. All of those cost more than a standard slab on ground.

Access and stairs change. A higher floor means more steps, a longer ramp if accessibility matters, and a rethink of how the house meets the yard.

Materials below the flood level are restricted. Anything below the flood planning level typically needs to be flood compatible: concrete, masonry, fibre cement, marine grade materials. Standard plasterboard and particleboard are not.

Services need to be raised. Switchboards, power points, hot water units and air conditioning condensers generally have to sit above the flood planning level.

Storage and enclosure below floor level is limited. Councils restrict enclosing under-floor areas so floodwater can pass through rather than being trapped.

Extensions on flood-affected land

An extension usually has to meet current flood requirements even though the existing house does not. That produces the common and awkward outcome of a new section sitting higher than the old one, resolved with a step or a ramp internally.

It also usually means a DA rather than a CDC, because flood-affected land is generally excluded from complying development.

Getting the information

Order a planning certificate, formerly known as a 149 certificate, from your council. It will state whether the land is flood affected and give you the relevant controls. It costs a small fee and it is the first thing to do before any design work.

For Maitland specifically, the council has detailed flood mapping and is used to dealing with these questions. Ask early rather than designing first.

Insurance and resale

Flood-affected land affects insurance premiums and lending. Building compliantly, with the paperwork to prove it, helps on both counts. Building non-compliantly creates a problem that surfaces at the worst possible time.

The practical view

Flood requirements are manageable when they are designed in from the start. They are expensive when they are discovered after a design is complete and everything has to move up 800mm.

We build across Maitland, Thornton, Rutherford and Raymond Terrace and we check the flood overlay before pricing anything, because it materially changes the job.