← All Insights

Contracts & Costs

How Much Does a Knockdown Rebuild Cost in Castle Hill?

A real 2026 cost breakdown for a knockdown rebuild in Castle Hill — demolition, reactive-shale footings, per-square-metre rates, approvals and the contingencies that protect your budget.

TL;DR In 2026, a knockdown rebuild in Castle Hill typically totals around $900,000 to $1.5 million-plus all-in, before land — because you already own the land. That covers demolition ($20,000–$45,000), the new build ($2,500–$4,500+ per square metre), engineered footings for reactive shale soil ($24,000–$42,000 on most blocks), and approvals and consultants ($15,000–$40,000). Castle Hill's specific cost drivers are its reactive clay soil, larger blocks, and the occasional slope or acreage site. This article breaks every line down so your budget is real, not a brochure figure. The build itself: per square metre The biggest line is the new home. As a 2026 Castle Hill guide: roughly $2,500–$3,500/m² for project-builder standard, $3,500–$4,200/m² for mid-to-high custom, and $4,200–$6,000+/m² fo…