Thinking About a Knockdown Rebuild in the Perth Hills? Here’s What You Need to Know

If you love where you live but your home no longer works for your lifestyle, knocking down and rebuilding might be the right move. Especially here in the Perth Hills, where the land is beautiful, but older houses often come with limitations—poor orientation, outdated layouts, or costly maintenance issues.

A knockdown rebuild gives you the chance to start fresh on your existing block and create a home that truly suits how you live now (and how you’d like to live in the future). But how much does it actually cost? And what’s involved?

Let’s break it down.

Demolition Costs

The first step is removing your existing home. In the Perth Hills, demolition costs usually range between $15,000 and $40,000, depending on:

The size of the house
Whether there’s asbestos (common in older homes)
Tree removal and access issues
The slope or complexity of the block

If your block is steep, has limited access, or sits in a bushfire-prone area, expect costs to be at the higher end.

Rebuild Costs

The cost of building your new home varies based on the style, size, and finish you’re after.

Project home (using a volume builder): $350,000–$600,000
Custom home (tailored design, suited to sloping or challenging sites): $500,000–$800,000+

Keep in mind, many Perth Hills blocks are not flat and often require a custom or adapted design. If you’re in a BAL-rated zone (Bushfire Attack Level), additional compliance measures (like ember-resistant materials and bushfire shutters) will increase your build cost.

Additional Costs to Factor In

Siteworks & retaining walls: $20,000–$100,000+
BAL compliance: $10,000–$50,000+
Driveways, fencing & landscaping: $20,000–$80,000
Temporary accommodation while you build
Septic system or alternative wastewater setup, if your block isn’t connected to mains sewer

These extras can really add up, especially on sloped or heavily vegetated blocks. That’s why it’s important to get a realistic site-specific estimate early on.

Don’t Forget Design Fees

The design phase is where everything begins—layout planning, orientation, material selection, and ensuring the house fits both your lifestyle and your block. In the Hills, where every site is different, good design is essential.

Here’s what you might expect to pay:

Building designer or draftsperson: $5,000–$20,000
Architect (for fully custom design): $20,000–$50,000+
Interior designer (for joinery, finishes, lighting & flow): $3,000–$15,000+ depending on scope

Well-considered design can save you money in the long run by avoiding mistakes, improving energy efficiency, and getting your layout right the first time. If you're planning a custom home on a sloping or bushfire-prone block, investing in design up front is absolutely worth it.

Is It Worth It?

If your home is dated, poorly laid out, or not energy-efficient—and you love your location—a knockdown rebuild can be a better long-term investment than an extensive renovation. You’ll end up with:

A home that suits your lifestyle and how you want to live
Better energy efficiency (and lower bills)
A layout designed around your block’s orientation
Compliance with current building standards, including bushfire protection

Plus, you get to skip the hassle of selling and moving!

Final Thoughts

A knockdown rebuild isn’t necessarily the cheapest or quickest path—but it can be the most rewarding. In the Perth Hills, where each block is unique, working with a builder or designer who understands the terrain, orientation, and bushfire requirements is essential.

At Bronika Carter Design, I offer practical advice and local knowledge to help you understand your options, whether you’re rebuilding, renovating, or just exploring ideas. If you’re wondering whether a knockdown rebuild could work for your block, feel free to get in touch.

No pressure—just honest, down-to-earth guidance from someone who lives and works in the Hills too.

Let’s chat about what’s possible.