So Why Doesn't Everyone Build Manor Houses?

Fair question. Three reasons.

Cost and complexity. Manor houses are Class 2 buildings under the Building Code of Australia. This means fire-rated construction, acoustic separation between dwellings, stricter compliance requirements, and higher build costs per square metre. The construction cost gap between a duplex and a manor house can be $400,000 to $600,000 on a comparable project.

Finance. Banks treat four-dwelling projects as commercial development rather than residential construction. That means higher interest rates, lower LVR (typically 65% of project value rather than 80%), and often presales requirements before funds are released. For first-time developers this can be a significant barrier.

Time. Manor houses must go through a full Development Application with council. No CDC shortcut available. Depending on site complexity and council workload, this adds four to eight months to your timeline compared to a duplex CDC. Holding costs during that period add up.