Short answer: it depends far more on which residential zone your block sits in than most people expect, and in Noosa the real question is not "can I build a duplex" but "is my block in Medium Density Residential." That is the one zone where a dual occupancy is genuinely provided for. Low Density Residential does not list it as a use at all, which pushes it to Impact assessment under the scheme's own default rule for an unlisted use. High Density Residential goes further and expressly excludes it. Noosa's duplex answer runs almost entirely through its Medium Density Residential zone; everywhere else in the residential zones, it is either discouraged or ruled out by name.
One thing is constant across all three: wherever a dual occupancy is not Accepted, it needs a real development application, assessed against the scheme's technical codes rather than decided by right. The category it lands in, Impact, Code, or excluded outright, is set by the zone table and the zone code's purpose statement, not by the block's size.
Why this is really an MDR question
Table 5.5.1, Low Density Residential's own table of assessment, does not list dual occupancy as a use. Under the scheme's default rule for a use not listed or defined in a zone's table, that silence routes an LDR duplex to Impact assessment, a discouragement set by the zone table itself rather than any overlay, and the firmest the scheme applies short of prohibition (verified 3 July 2026).
Medium Density Residential is a different scheme altogether. Table 5.5.2 lists Dual Occupancy as Code assessment, assessed against the Local Plan Code, the Medium Density Residential Zone Code, and the Dual Occupancy and Multiple Dwelling Code, rather than defaulting to Impact. That row carries its own siting conditions, expressed in our fact set as two limbs: the lot is not one of three named Sunshine Beach parcels, or the lot is under 600 m². Exactly how those limbs combine on a specific lot is confirmed against Table 5.5.2 at the point of use rather than assumed here. What is firm is the category: outside those named exceptions, an MDR dual occupancy is Code assessable, not Impact assessable, which is the gap that makes MDR the real duplex zone in Noosa.
The MDR bulk numbers, and what they mean for a two-dwelling design
Medium Density Residential's zone code sets the envelope a dual occupancy design has to fit inside: a minimum lot of 600 m² and 17 m of width (Table 9.5.1.4, verified 3 July 2026), a maximum height of 8 m and 2 storeys, site cover of 40% (45% where the mix is all small dwellings, or small dwellings sit in at least a 3:1 ratio to other dwellings), and a plot ratio of 0.4:1, rising to 0.5:1 under the same condition (verified 3 July 2026). Read literally, a 0.4:1 plot ratio on a 600 m² lot caps the combined gross floor area of both dwellings at roughly 240 m², before any setback, landscaping or car parking requirement eats into what is left of the site; that is an illustrative reading of the ratio against the minimum lot size, not a promise that any particular block yields that figure once its own shape and setbacks are read.
A design screen sits on top of those numbers, worth checking first: the Dual Occupancy and Multiple Dwelling Code rules out battle-axe and rear lots, and any lot with a frontage under 10.5 m. A block that clears the 600 m² and 17 m minimums can still fail this test on shape alone, exactly the kind of thing a lot-by-lot check reads rather than assumes from the zone table.
HDR: the multiple dwelling reroute
High Density Residential does not treat dual occupancy the way Medium Density Residential does, and the difference is not silence, it is an express exclusion written into the zone code's own purpose statement (Section 6.3.3, verified 7 July 2026):
"to the exclusion of dual occupancy and dwelling houses"
That clause is the zone code's own statement of what the zone is for: multiple dwellings, to the exclusion of dual occupancy and dwelling houses. Table 5.5.3, the zone's table of assessment, is consistent with it and does not list Dual Occupancy as a use at all. In practice, a two-dwelling proposal on an HDR lot is not assessed as a dual occupancy; it proceeds as a Multiple dwelling, which Table 5.5.3 lists as Code assessment through a three-limb test whose third limb is simply "on any other sites," in effect Code assessable in every case (verified 3 July 2026). The zone's 12 m/3-storey height cap and 0.65:1 plot ratio, Noosa's most generous residential bulk settings, apply to that multiple dwelling pathway, not to a use the zone code has already excluded by name.
The flood divergence: a duplex is Code where the house next door stays Accepted
Noosa's Flood Hazard Overlay (Table 5.9.6, verified 7 July 2026) does not treat every residential use the same on flood-affected land, and the gap matters specifically for a duplex. A dwelling house, which under the standard Queensland definition includes a secondary dwelling (granny flat), is Accepted development on flood-affected land. A dual occupancy is not covered by that carve-out; it falls to the table's "if not otherwise specified" limb, which is Code assessment.
So on the same flood-affected block, a granny flat can stay Accepted while a duplex needs a Code assessable application, purely because of what the overlay does to that specific use, on top of whatever the zone's own dual occupancy category already requires. Reconfiguring a lot on flood-affected land is Code assessment across the board regardless of use, so a subdivision offers no escape from this either. Exactly where the mapped 1% AEP flood extent sits on a given parcel is a mapping question a site-specific check reads against the block, not something this page can answer in general terms.
Titling: why "duplex" does not mean the land splits
A dual occupancy approval is a use approval, not a subdivision. The land stays one lot. What makes a duplex saleable as two separate assets is a Building Format Plan, a community-title process applied over the approved building, sold under LandIntel's standard product definitions as sell one, keep one. That titling step is its own process, confirmed by your solicitor or planner for the specific proposal, not an automatic consequence of the dual occupancy use being approved.
Keep it separate from the subdivision numbers. Medium Density Residential's minimum lot size for reconfiguring a lot is also 600 m² with 17 m of width, the same figures that describe the zone's dual occupancy siting condition above, but that land-density minimum governs a freehold, Standard Format Plan split into two new lots; it does not govern the Building Format Plan strata step over an approved dual occupancy building, a different title mechanism entirely. A lot too small or oddly shaped to produce two freehold lots under Table 9.5.1.4 can still carry an approved dual occupancy that later strata-titles under a Building Format Plan, because the two processes are not testing the same thing.
How to check your own block
- Confirm the zone: Low, Medium or High Density Residential. That single fact decides whether a duplex is Impact assessable (Low), Code assessable (Medium), or excluded in favour of a multiple dwelling pathway (High).
- If the lot is Medium Density Residential, check it against the 600 m²/17 m minimum, the 10.5 m frontage and non-battle-axe, non-rear-lot test, and the two named-lot/under-600 m² conditions in Table 5.5.2 before assuming Code assessment applies without further conditions.
- Check the Flood Hazard Overlay mapping on the parcel. A dwelling house or granny flat can stay Accepted where a dual occupancy on the same land needs a Code assessable application.
- If a Building Format Plan title is the goal, treat it as a separate step confirmed by your solicitor or planner once the use approval is in hand, not something the dual occupancy approval delivers automatically.
This page is general information about the Noosa Shire planning scheme, not advice about your property. Overlay effects and flood mapping vary lot by lot, planning schemes amend, and the council's current scheme prevails. Do not rely on this page for a specific property. Get a site-specific report or independent professional advice before acting. We work with town planners, not in place of them: where a pathway depends on design or professional judgement, a town planner or the relevant qualified professional confirms it for your specific proposal.
Want the answer for your block? Our $690 site-specific report reads the zone, every overlay mapped on the property and the surviving development pathways for one property, with every figure cited to the scheme. Not ready for that? Start with the free development risk checklist, read our Noosa planning and zoning guide, or check whether your block can instead be subdivided or carry a granny flat.
Sources: Noosa Plan 2020 (the council's official ePlan), including the Low, Medium and High Density Residential Tables of Assessment (5.5.1 to 5.5.3) and zone codes (6.3.1 to 6.3.3), the Dual Occupancy and Multiple Dwelling Code (9.3.3), Table 9.5.1.4 Minimum Lot Size, the Flood Hazard Overlay Code and Table 5.9.6, and section 5.3.2 Categories of development and assessment. Everything on this page comes from the council's own published planning scheme; we explain it in plain English. The scheme text itself is the authority.
Published by LandIntel. How we research: our methodology.
Verified 3 to 7 July 2026 against the Noosa Plan 2020, Amendment 3 (effective 20 March 2026); schemes amend, and the live scheme prevails.