Open-plan living works when you plan the space as three or four defined zones that happen to share one volume. It fails when you plan it as one big room. On Sunshine Coast and Noosa jobs the parts homeowners love are consistent — sightlines from the kitchen to the pool, the connection out to a covered deck, the light. The regrets are just as consistent, and there are only three: noise, heat and glare, and nowhere to put anything. All three are design decisions rather than construction faults, and all three are far cheaper to solve on paper than after the plasterboard is on.
What an open plan still has to deliver under the NCC
Before the aesthetics, the space has to work as a habitable room. NCC 2022 Housing Provisions clause 10.5.1(2)(a)(i) requires windows with an aggregate light-transmitting area of not less than 10% of the floor area of the room, or under 10.5.1(2)(b)(i) roof lights of not less than 3%, and clause 10.6.2(a)(i) requires a ventilating area of not less than 5%. Merge a living room, dining room and kitchen into one 60 m² space and those percentages apply to 60 m², not to three smaller rooms. If the glass is all at one end, the far end is borrowing light and air, and clause 10.6.2(b) allows that only where the adjoining room has a window, opening, door or other device with a ventilating area of not less than 5% of the combined floor areas of both rooms. Deep, single-aspect open plans therefore need high-level louvres, a roof light or glazing on a second wall.
Acoustic, thermal and storage trade-offs, with the fixes
This is the table we work through before a single wall is deleted. The design-stage fixes are the cheap ones; the retrofit column exists because most people find the problem in their first summer.
| Trade-off | Why open plan causes it | What you notice | Fix at design stage | Fix after the build |
|---|---|---|---|---|
| Acoustic: reverberation | Hard floors, stone and glass in one large volume, with nothing soft to absorb sound | The TV goes up two notches; a dinner for eight is exhausting by dessert | Break up the ceiling plane, line part of it in timber or acoustic-perforated board, design in a rug zone, heavy curtains over blinds | Rugs, upholstery, curtains, acoustic panels — limited once the hard surfaces are set |
| Acoustic: no code protection | NCC Housing Provisions Part 10.7 regulates separating walls only — a wall between two Class 1 buildings, or between a Class 1 building and a Class 10a building not associated with it, at Rw + Ctr not less than 50. Nothing in it governs internal walls inside your own house | You hear the media room, the study call and the bedroom from the kitchen island | Specify it yourself: batts in internal walls, a second layer of dense plasterboard to the media room and main bedroom, solid-core doors | Strip and re-sheet the wall, then cornice, skirting and paint make-good |
| Acoustic: kitchen noise | The dishwasher, rangehood and kettle now sit inside the living room | Cleaning up after dinner shuts down conversation and the television | A scullery behind a wall, the dishwasher off the seating side of the island, quiet-rated appliances, a remote-mounted hood motor | New appliances, or a door to the pantry opening if the framing allows |
| Acoustic: cooking odour | Odour travels wherever sound travels. There is no door between the wok and the sofa | Soft furnishings hold last night’s dinner | NCC clause 10.8.2(1) sets a minimum exhaust flow rate of 40 L/s for a kitchen and clause 10.8.2(2) requires exhaust from a kitchen or kitchen range hood to discharge directly, or via a shaft or duct, to outdoor air. Size above that minimum, duct the shortest run, and allow the make-up air clause 10.8.2(5) calls for — openings to an adjacent room with a free area of 14,000 mm², or to AS 1668.2, unless the room is naturally ventilated under 10.6.2(a) | Re-duct a recirculating hood out through the ceiling or roof |
| Thermal: summer heat gain | Open plan is sold with a wall of glass, and glass is the weakest part of the envelope | The room is unusable from 2pm to 5pm in February unless the air conditioning works hard | NCC clause 13.3.3 caps the aggregate solar heat gain of the glazing in each storey against the floor area of that storey, and the note to Figure 13.3.2b treats an external shading device complying with 13.3.4(b) as achieving a projection-to-height (P/H) value of 2.00. Eaves, screens, low-SHGC glass and orientation | External blinds, awnings or a pergola. Applied film helps at the margin only |
| Thermal: you cannot zone it | One volume must be cooled as one volume, even when two people use one corner of it | Running costs out of proportion to the household | A ducted system splitting the open plan into two zones, with separate bedroom systems. NCC Volume Two clause H6P2(1) requires the energy value of a home’s domestic services not to exceed 70% of the energy value calculated with the reference services that clause lists | Zone motors and a controller if the ducting allows; otherwise a second system |
| Thermal: mandatory ceiling fans | NCC 2022 clause 13.5.2 requires ceiling fans to be installed in accordance with Table 13.5.2 in habitable rooms in climate zones 1, 2 and 3, and in climate zone 5 in New South Wales and Queensland | Three large fans landing in a ceiling you drew as a clean raked plane with pendants | For a habitable room other than a bedroom, Table 13.5.2 calls for two 1400 mm fans from 30 m² to under 45 m², three 1200 mm fans from 45 m² to under 50 m², and three 1400 mm fans at 50 m² or more. Set fans, lights and speakers on one reflected ceiling plan | Very little. Positions are fixed by joist direction, blocking and wiring |
| Storage: deleted walls are deleted joinery | A 4 m wall removed is 4 m of potential cupboard or shelving gone with it | Bags, sports gear and paperwork living on the dining table | Count the linear metres of storage in the existing plan and beat it before you sign off. Full-height joinery walls, under-stair storage, window seats with drawers | Freestanding furniture, which eats the floor area you paid to open up |
| Storage: nothing can be hidden | There is no door to close on a half-finished job or a loaded bench | The island becomes the drop zone for everything carried in | A scullery, an appliance garage with a roller door, and a real drop zone with hooks and a cupboard at the entry you actually use | Baskets and canisters, which is management rather than a fix |
Where the walls should stay
The regret we hear on site is rarely that a home was opened up. It is that one wall too many was opened up. Four walls usually earn their keep: the media room wall, because one closable room changes how teenagers and adults share a floor; the scullery wall, which hides the mess, the noise and the small appliances; the laundry wall, since clause 10.8.2(1) applies the same 40 L/s exhaust minimum to a laundry and that is easier to duct from an enclosed room; and the entry wall, which keeps a buffer between the front door and the good room. Walls also do structural work — removing a loadbearing wall means a beam, a load path down to adequate footings, and often a rework of the bracing that AS 1684 Residential Timber-Framed Construction requires the frame to carry.
The things nobody regrets
Ceiling height buys more than almost any finish you can spend the same money on, because you are paying for framing and lining rather than for materials. NCC clause 10.3.1(1) sets the minimum at 2.4 m for a habitable room other than a kitchen, and 2.1 m for a kitchen or a corridor — floors, not targets. Lifting or raking the living zone is the change clients mention most walking back through a finished job. The short list after that: a covered outdoor room that genuinely extends the living space, a kitchen bench set so whoever is cooking faces the room, and glass moved off the western wall onto a northern one. On the Grandview Drive project at Coolum Beach the internal volume was planned around the way it opens out to the outdoor living and pool area. It won three Master Builders Queensland 2025 Sunshine Coast Housing & Construction Awards — Home Renovation/Remodelling Project over $1 million, Best Residential Swimming Pool and Best Use of Innovation — presented on 15 August 2025 at The Events Centre, Caloundra.
Getting it approved and built on the Sunshine Coast
Opening up a floor plan is a building approval matter, and if you change the footprint or roof form it can be a planning matter too. Sunshine Coast Council administers the Sunshine Coast Planning Scheme 2014, which the council records as gazetted on 2 May 2014 and commenced on 21 May 2014, and Noosa Shire Council administers The Noosa Plan 2020. Which assessment applies depends on your zone, the overlays affecting the land and the scale of the work — see our guide to building approvals on the Sunshine Coast and Noosa. On contracts, the QBCC requires a domestic building contract to be in writing and to comply with Schedule 1B of the QBCC Act, and sets the levels by value: a level 1 contract covers renovation, extension and routine repair work from $3,301 to $19,999, and a level 2 contract covers work of $20,000 and over. Any structural opening-up job sits in level 2 territory.
We plan open-plan spaces as part of a full custom build or major renovation, working alongside architects including K Architecture and Reitsma & Associates on projects from Nairana Rest at Noosa Heads to Columba Place at Pelican Waters. If your open plan centres on a new kitchen, the cost drivers are in our guide to kitchen renovation costs in Queensland, and the resale case is set out in renovations that add value in Queensland.
Frequently asked questions
Is open-plan living going out of fashion?
No, but the fully undivided plan is. What clients ask for now is open plan with one or two closable rooms attached, usually a media room and a scullery. You keep the light and the sightlines without the acoustic and mess problems of a single volume.
How do I stop an open-plan room echoing?
Absorption and geometry. Break up the ceiling plane, design in soft surfaces rather than leaving them to the furniture, insulate internal walls even though NCC Part 10.7 applies only to separating walls and not to walls inside a single dwelling, and use solid-core doors. AS/NZS 2107 Acoustics — Recommended design sound levels and reverberation times for building interiors is the standard an acoustic consultant works to if the space warrants one.
Do I really need three ceiling fans in my living room?
If the room is a habitable room other than a bedroom, is 50 m² or more, and your site falls in a climate zone caught by NCC 2022 clause 13.5.2, Table 13.5.2 calls for three 1400 mm fans. Your energy assessor confirms the climate zone for your address. Coordinate it into the ceiling design early rather than discovering it at frame stage.
Will a wall of glass fail the energy assessment?
It can. NCC clause 13.3.3 limits the aggregate solar heat gain of the glazing in each storey against that storey’s floor area, and clause 13.3.2 applies a separate winter check on the ratio of conductance to solar heat gain, measured against the allowances in Table 13.3.2a. Large glazing usually still complies, but only with the right glass, orientation and external shading — which is why eaves and awnings are often worth more than upgraded glass here.
Can I remove a wall without an approval?
Assume not. Structural work needs building approval, and the beam sizing, load path and bracing have to be documented by an engineer. Confirm your builder holds a QBCC licence covering the work before you commit — here is how to check a QBCC licence on the QBCC online licence register.