It's amazing how much renovation advice gets handed around at a BBQ. The problem is, much of it is outdated, and in today's environment, where costs, compliance and timelines have all shifted significantly, those assumptions can derail even the best intentions. James Pilcher, Founder and Director of MILEHAM Architects + Builders, breaks down the six most common myths he encounters, and what every homeowner needs to know before they begin.

Myth 1: Price Per Square Metre is Your Budget Bible

Reality: It's an understandable shortcut. Multiply a rate by your floor area and suddenly you have a number to work with. The problem is, it's rarely the right number. Two homes of identical size can vary by hundreds of thousands of dollars depending on site constraints, glazing, joinery detail, sustainability requirements and finish level. Real cost clarity comes from detailed documentation and a proper understanding of your specific site, not a figure borrowed from a conversation at the weekend. "Two homes of the exact same size can vary by hundreds of thousands of dollars, depending on specification, site constraints and build complexity," says James.

Myth 2: Your Designer Can Cost the Whole Build

Reality: Your designer is an incredibly valuable part of the process, brilliant at shaping beautiful spaces and bringing your vision to life. But the full cost of a build goes well beyond fixtures and finishes. Site establishment, demolition, structural take-offs, labour rates, insurance premiums and compliance costs all sit firmly in the builder's world. Bringing a builder into the conversation from your very first concept design ensures your vision and your budget are always telling the same story. At MILEHAM, that builder's perspective comes in from day one.

Myth 3: Renovating Always Beats Rebuilding

Reality: It seems obvious that keeping what you have should cost less. But once demolition begins, hidden structural issues, outdated services and non-compliant elements have a way of making themselves known. Suddenly working within existing constraints becomes far more complex, and far more expensive, than anticipated. A knockdown rebuild can deliver better long-term value, performance and layout efficiency than many homeowners expect. It's always worth asking for a feasibility assessment before you commit to either path. "Sometimes a knockdown rebuild delivers better long-term value, performance and layout efficiency than renovating an existing structure," James explains.

Myth 4: You'll Save Money Project Managing Yourself

Reality: It's a natural instinct. You know your home, you're organised and you're motivated to keep costs down. But managing a major renovation today involves carefully timed trade schedules, compliance approvals and workflows that depend on everything running in the right order. One delay can create a domino effect through your entire timeline. Many trades won't even come on board without a professional project manager in place. And nine times out of ten, homeowners who take it on themselves don't save money. They just absorb the stress themselves.

Myth 5: The Lowest Quote Protects Your Budget

Reality: Choosing the lowest number feels responsible. In reality, low quotes are often built on provisional sums and rough estimates that leave plenty of room for invoice shock further down the track. A detailed, accurately costed quote might feel higher at the outset, but it's the one that gives you a true picture of what your project will actually cost, and the best chance of finishing without nasty surprises.

Myth 6: Allow 12 Months for a Major Extension

Reality: If only. Most Sydney councils now advise three months for the approval process alone. For a DA-approved major alteration, you're looking at nine to twelve months for design development and approval, then a further six to eight months for construction. Eighteen months is a realistic minimum, and building that into your planning from the start makes for a much smoother, less stressful experience all round.

Renovate with Clarity, Not Assumptions

When architecture and building expertise sit under one roof, the whole process feels different. You're not managing two conversations and hoping they align. You have one team, one vision and genuine clarity from the very first site meeting. That's exactly what MILEHAM offers, as both a registered architect and licensed builder, every step of the way.

Ready to start your project on solid ground? Your next chapter starts with the right conversation. Reach out to the MILEHAM team today at mileham.com.au.

1/2 Moore Rd, Freshwater 2096 | 0410 723 203 | @mileham.group | mileham.com.au