Gold Coast Granny Flat Designer — Licensed Builder + Designer on Your Side

Custom Granny Flat Design for Your Block

Every Gold Coast granny flat project is different — block size, orientation, the existing dwelling, your budget, and how you want to use the space all change the right answer. We design across the full range of configurations homeowners actually ask for, not a single plan repeated with different wallpaper.

Detached 1-bedroom (45–60sqm): the most common configuration — one bedroom, bathroom, open living/kitchen, usually at the rear of the block. Works for in-law suite, teenager retreat, rental, or short-stay.

Detached 2-bedroom (60–80sqm): the QLD Class 1a secondary-dwelling maximum. Most family-rental briefs fit here. Careful space-planning matters — two bedrooms in 80sqm is tight, and how the plan treats storage, laundry, and entry decides whether it feels like a real home or a compromise.

Garage conversion: cheaper than a new build but constrained by slab height, door openings, ventilation, and egress rules. Works well when the existing footprint is already well-placed.

Above-garage / second-storey: frees up yard, can deliver views, suits sloping blocks. Structural and fire-separation adds cost but yield per square metre is the highest of any configuration.

Attached (dual occupancy): sometimes the better planning answer on smaller lots or corner blocks. Has dual-occupancy planning implications on some Gold Coast zones — we check your zone and overlays before you commit.

Granny Flat Design Fees — From $3,000

Design fees start at $3,000 for a straightforward detached 1-bedroom granny flat with no site complications. From there, fees scale with size, complexity, slope, overlay constraints, and whether you want construction-support included through to practical completion. Every quote is confirmed in writing after the $280 consult — nothing is hidden, no value-engineering surprises later.

What drives the fee:

• Size and configuration: 1-bedroom is cheapest; 2-bedroom, above-garage, and attached configurations cost more to design because there’s more to get right.
• Block complexity: a flat block with no overlays sits at the base fee. Sloping blocks, flood, bushfire, acid sulfate, and heritage overlays all add design work.
• Level of construction support: plans-only is the base fee. Adding tender review, builder Q&A, and practical-completion support is priced as a day-rate add-on, not a percentage.
• Documentation depth: some builders price off concept-level plans, some want full-detail construction documentation. We scope this at the consult so there are no mid-project surprises.

The $280 consult fee is credited against your design contract if you proceed. It’s not a free assessment — it’s a paid hour with a builder-designer, and it’s how we make sure the advice we give is straight.

Why Our Granny Flat Plans Survive the Build

A set of plans is a theory until a builder prices them. Most “design fails” happen in the gap between what the designer drew and what the builder found when they started putting it together. Because we build as well as design, we close that gap at drawing stage, not at site meeting #3.

Construction tolerances are drawn in, not assumed. Frame widths, slab tolerances, wall build-ups, floor-to-ceiling heights — the numbers we put on the plan are the numbers the builder can actually build to. You don’t get to site and discover the plan was drawn at “ideal” and the real-world build needs a redesign.

Service runs are drawn before the walls are fixed. Sewer, water, stormwater, electrical mains, data, gas — we lay them out at design stage, not “to be coordinated on site”. This matters especially on granny flats, where services connect back to the primary dwelling through a yard path rarely as straight as the cost plan assumed.

Slab design is matched to the block, not the plan. If your block has reactive soil, fill, or is near a watercourse, the slab design changes — and that changes cost. We flag slab variability early so the builder’s quote is priced against reality, not a default P-class assumption.

Our design process runs five steps — consult, site + brief confirmation, concept design with cost ranges, council-ready plans, and optional construction support — on average 4–8 weeks from consult to council-ready plans.