Services
Two homes on one block, designed to get approved
Custom duplex design for Central Coast sites, from concept through DA, CC or CDC. Indicative fees from $50,000; start with a $220 consultation, credited if you proceed.
The block is worth more than the house sitting on it
All over the Central Coast there are wide, tired blocks holding one small house, in suburbs where two modern homes would thrive. If you own one, you have probably done the mental arithmetic: parents in one side, income from the other. Sell one, keep one. Build two and sell both.
The arithmetic is the easy part. Between the idea and the approval sits a thicket of controls: zoning, minimum lot requirements, overlays and the design standards a duplex must meet. Get them right and a duplex is one of the most efficient projects a land owner can build. Get them wrong and you own a very expensive set of unapprovable drawings.
The difference is almost never luck. It is the order you do things in.
What you get
Feasibility before fees. We never design first and check second. Your block's zoning and controls get verified against the actual planning instruments before serious money is spent, and our dual occupancy feasibility guide shows you the questions we ask. If the block cannot carry a duplex, you find out at the cheapest possible moment.
A custom design, not a mirrored box. Most duplexes are one plan flipped down a party wall, which is why most duplexes feel like halves rather than homes. We design both dwellings for the site: light and privacy for each, outdoor space that belongs to each home, street presence that lifts the block instead of cheapening it. It is the difference between two homes and two halves, and it shows at sale and rental time.
The approval pathway handled. Concept through DA and CC, or CDC where your project qualifies, with documentation prepared for approval rather than argument. Browse our duplex resources to see how we think about these projects.
A designer with developer scars. Duplexes sit at the small end of development, and development is where we have done our largest work. Shea was project architect for an 89 apartment seniors living development, where her floor space ratio solution gave the client twenty more apartments than they thought the site allowed. That instinct, finding the value the controls actually permit, scales down to a duplex beautifully.
This is for you if
- You own a Central Coast block and want to know, honestly, whether a duplex works on it.
- You are hunting for a duplex site and want professional eyes on the shortlist before you buy.
- You have a duplex project that stalled, with another designer or at council, and need it rescued or rethought.
It is not for you if you already know a granny flat better fits the goal and the budget; check our granny flat resources and we will tell you straight in the consultation which path your block favours.
How it works
- Book the $220 Initial Consultation below. It is credited toward your project fee if you proceed.
- We assess the block and, where the answer is not obvious, recommend a feasibility study so the go or no go decision is documented.
- You receive a fixed fee proposal, then design proceeds stage by stage through to approval.
Shea created a solution for FSR that allowed us to have an additional twenty apartments, generating millions in additional revenue.
Your investment
Duplex Design
$220 to start
Indicative pricing: from $50,000 for a custom duplex.
Covers Concept plus DA/CC or CDC. Tender documentation optional at additional cost. Start with a $220 Initial Consultation, credited toward the project fee if you proceed and not refundable if you do not.
All prices are in Australian dollars and include GST. Standard Conditions of Engagement · NSW Code of Conduct (PDF)
Questions people ask us
Will my block even allow a duplex?
That is always the first question, and we answer it with research rather than guesswork. Zoning, lot size, frontage and overlays all matter, and the controls are specific to your site. The $220 consultation gives you an early professional read, and a feasibility study documents the answer properly before you commit to design fees.
What does 'from $50,000' cover?
Concept design through the approval pathway: DA and CC, or CDC where the project qualifies. Tender documentation for pricing and construction is optional at additional cost. You get a fixed fee proposal before any design work begins, and the $220 consultation is credited against it.
Should I build a duplex or a granny flat?
They are different tools. A granny flat is cheaper, faster and keeps one title; a duplex costs more but can create two genuinely separate homes. Which is right depends on your block, your goal and your budget, and giving you a straight answer to exactly that question is what the initial consultation is for.
Can you help me work out if the numbers stack up?
Yes. Feasibility is where every good duplex starts, and our dual occupancy feasibility guide walks through the thinking. When you want it done on your actual block, that is a feasibility study, and it slots in before the design fee, not after.
Imagine your block working twice as hard, with a design that council can approve.
Book Initial Consultation