60 Sqm Granny Flat Costs NSW 2026 - Get Free Quotes

60 Sqm Granny Flats in NSW

Sixty square metres is the number attached to secondary dwellings more often than any other in New South Wales, and a dwelling built at or near it costs $150,000 to $220,000. Around that build sit smaller professional costs that determine whether the design works at all: $300 to $800 for a floor area check on a drawing, $500 to $2,500 for a written planning assessment, $800 to $2,500 for a concept design and $600 to $2,000 to redraw a plan that has failed on area. That last figure is the one worth avoiding. Every one of those smaller items exists to prevent a much larger problem downstream. Spending a few hundred dollars early is the cheapest insurance available on a project of this size. Comparable pricing by bedroom count sits at two bedroom granny flat costs.

Treat the figure itself with some care. It is a maximum rather than an entitlement, the numbers attached to these criteria have been amended more than once in recent years and remain under review, and the area actually available on your block may be lower than any published figure once the other controls are applied. What the number is on a given day is a question for your council or a registered certifier rather than for any website, and the criteria generally are set out at granny flat rules. Any published number, including the ones appearing on this page, is background information rather than an answer for your site. A registered certifier will confirm the current position for your property quickly, and a duty planner at the council will do it for nothing.

The measuring causes more difficulty than the number. Households and builders both talk about floor area as though it were one dimension anyone could take with a tape, when it is a defined calculation that treats an enclosed room, a roofed but open alfresco, a porch, an external store and a carport differently according to how each is built. Two dwellings that look completely identical from the street can be counted quite differently, and that difference decides which approval pathway remains available to you. Nobody sets out to mislead anybody here, and the calculation is simply a good deal less intuitive than it first sounds.

Where the Figure Comes From

A maximum floor area has applied to secondary dwellings in this state for many years and sixty square metres is the figure most commonly cited. It exists to control density, so that a second dwelling on a suburban block remains secondary in scale to the house it sits behind rather than becoming a second house in its own right. Reading it that way explains a good deal about how it is applied, because the intent is proportion rather than an arbitrary limit on your ambitions. Understanding the purpose makes the control far easier to work with than treating it as an obstacle. It also explains why the answer to a borderline question is usually no. Proportion rather than restriction is the idea behind it.

The figure has been subject to change over the years and should always be confirmed rather than assumed. These criteria have moved more than once lately and are still being looked at, so a number accurate at publication may not survive to your reading of it. This page uses sixty because that is the figure attached to the searches people make, and it should be treated as a starting point for a conversation with your council rather than as the answer for your land. Ask specifically when the figure you are being quoted was last amended, since that single question tends to produce a considerably more careful answer. Builders' websites, older articles and forum posts all carry figures that were correct when written, and there is no way to tell which still stand.

Some councils apply their own controls alongside the state framework and those can affect the outcome. A local environmental plan or development control plan may address matters such as building bulk, private open space or the relationship between the two dwellings in ways that shape a design even where the headline area is satisfied. Asking the council's duty planner what applies in that area is a free call that resolves most uncertainty. Planning services run through Service NSW. Have your lot and deposited plan numbers to hand before you ring, since the answer depends on the property rather than the suburb. Both documents are published on the council website, though they are written for planners rather than householders.

Where a proposal exceeds the applicable area by any margin, the fast pathway closes entirely and a merit assessment becomes the only remaining route. That is a genuine alternative rather than a refusal, and a great many larger secondary dwellings are approved through it, though it takes months rather than weeks and costs more in fees and consultants. Whether the extra area justifies that trade is a calculation worth doing explicitly, and that route is described under granny flat approval. Neighbours are also able to make submissions on that route, which becomes a further consideration wherever a larger building is being proposed close to a shared boundary.

The figure is also worth understanding as a design brief to work within rather than as a restriction to resent. Sixty square metres accommodates a genuinely comfortable two bedroom dwelling when the plan is efficient, and a cramped one when it is not, and the difference lies entirely in how the area is allocated. Designers who work to this cap regularly produce noticeably better outcomes at the same area than those who treat it as a stretched version of something larger. Ask to see two or three completed examples built to the same area before forming any view about what the figure actually delivers. Five minutes standing inside a finished one teaches you what a fortnight of studying drawings cannot.

What Gets Counted in the Measurement

The enclosed and roofed part of the dwelling is counted toward the total, and that much of it is never in dispute anywhere. Living areas, bedrooms, the kitchen, the bathroom, the laundry, hallways, built in robes and any internal storage all form part of that figure. Circulation counts toward the total even though nobody actually lives in it, which is one reason an efficient plan delivers noticeably more usable space at the same measured area than an inefficient one does. There is no version of the calculation where habitable rooms sit outside it, so the question is always about the spaces at the edges.

How exactly the measurement is taken at the walls is worth establishing early rather than assuming. Whether the area is measured to the internal face of the walls, to the external face, or to some other defined line changes the total by a meaningful amount across a whole dwelling, and different controls have taken different approaches over time. On a sixty square metre building the difference between measuring inside and outside the wall can approach three square metres, which is more than most people would guess. Ask which line on the drawing the figure has been measured to, and get that answer in writing rather than in conversation. Across a whole dwelling of this size the difference between the two approaches is considerably larger than most people would guess.

Wall thickness therefore matters to the final figure, which routinely surprises households and never surprises a designer. A dwelling built with a thicker external wall build up, whether for insulation, acoustic performance or a masonry finish, occupies more area for the same internal result if the measurement is taken externally. This is one of several reasons a designer will ask what construction system is intended before drawing anything, and construction methods are covered at granny flat construction. Insulated panel, timber frame and masonry veneer construction all produce quite different wall build ups for exactly the same internal dimensions.

Internal voids, raked ceilings and mezzanine spaces all raise questions of their own, and the answers are not remotely intuitive. A raked ceiling adds volume without adding floor, which is why it is such an efficient way to make a capped plan feel larger. A mezzanine or loft that can be occupied is a different matter and may be counted, so anything above head height in a design is worth querying specifically before it is drawn in. Head height is generally the trigger for the distinction, so a low storage platform is treated differently from a space somebody could stand upright in.

The practical instruction is to ask your certifier how the calculation is defined for your particular proposal, in writing, before any documentation work begins. Certifiers apply this daily and will answer a precise question quickly. Anyone who has worked with the same certifier before will usually know the answer already, and the certification process is described at granny flat complying development. Put the question in an email so that the answer exists as a written record you can point back to later. Certifiers answer a precise question quickly and a vague one slowly, so ask specifically about your own proposal rather than in general terms.

Alfrescos, Porches, Stores and Carports

This is where designs come unstuck and it happens with some regularity. A covered outdoor area may be counted, partly counted or excluded depending on how enclosed it is, how it is roofed and how it relates to the rest of the building. The same twelve square metres of alfresco can sit inside or outside your sixty according to whether it has two walls or none, whether the roof is continuous with the dwelling or separate, and how open the remaining sides are. Builders advertising a sixty square metre design with a generous alfresco are not necessarily wrong, and the counted total on your block is a separate question. Configuration decides the treatment rather than the name on the plan. Twelve square metres of alfresco is the difference between a compliant plan and a merit assessment.

Porches and entry canopies are usually modest enough not to threaten a plan on their own, and they still deserve a direct question. A small roofed entry protecting the door from weather is worth having and rarely contentious, while an entry that has grown into a covered sitting area with walls on two sides is a different proposition. The line separating the two is rarely obvious from a drawing alone, which is exactly why it needs confirming rather than assuming. The depth of the space and the presence or absence of side walls are the two features that change how it gets treated.

External storage attached to the body of the dwelling is frequently overlooked in the calculation and just as frequently counted toward it. A store accessed from outside, tucked under the same roof and enclosed on all sides, looks like a shed to the household and looks like floor area to the certifier, which is a gap in perception worth closing early. Where storage is genuinely needed and the area is tight, a freestanding shed elsewhere in the yard is usually the better answer, and it takes nothing from the dwelling. Households think of it as a cupboard and the calculation frequently thinks of it as a room.

A carport or a covered parking space attached to the secondary dwelling raises the same question again. Whether it counts depends on its configuration and on the controls applying, and the answer can be the difference between a compliant proposal and one that has to be redrawn. Where parking is required for the dwelling, establish early how the structure providing it will be treated. Whether the parking must be covered at all is worth checking before a structure is designed for it.

The reliable approach is to have the designer mark on the concept plan which areas are counted and which are not, with a total shown. That single annotation makes a drawing checkable by you, by the builder and by the certifier, and it forces the question to be answered at the point where changing the design still costs nothing. Sample arrangements appear at granny flat floor plans. Any competent designer will do this without the slightest objection, and reluctance to do so tells you something worth knowing.

Your Own Permissible Area

Sixty square metres is a ceiling and not an allowance, and a good number of blocks cannot reach it. Site coverage limits how much of the property may be built upon, counting the house, the garage, any shed and often paving, and a block already carrying a generous dwelling and a double garage may have very little coverage remaining. Measuring what already exists is the step that reveals this. Where that limit binds before the floor area does, the floor area figure becomes irrelevant to you. Establishing that early prevents a great deal of wasted design effort. A good number of blocks never get near it.

Landscaped area works alongside coverage and reduces the available envelope further. Requirements for permeable, planted area frequently carry minimum dimensions, so a narrow strip along a boundary may contribute nothing toward the total. Extensive paving, a pool surround and a generous driveway together can push a block past this control while looking green from the street. Replacing paving with permeable surfaces is sometimes an answer, though it needs confirming rather than assuming. Minimum dimension requirements are the detail people miss, and they are stated in the controls.

Setbacks then determine where the remaining envelope actually sits, which is a separate question from how large it is. A block with adequate coverage available may still be unable to accommodate a sixty square metre rectangle once front, side and rear setbacks are marked out, particularly where the shape is irregular or the block is narrow. Pegging the setbacks on the ground is the fastest way to understand what you are working with. String and pegs on a Saturday morning tell you more than a fortnight of looking at plans.

The sensible sequence is to establish your own permissible area first, before anything at all is drawn. A written planning assessment at $500 to $2,500 states what is available on your specific property and on what basis, and it costs a fraction of a redraw. Households who commission a design first and check afterwards are the ones who pay for it twice over, and the general framework is covered at granny flats in NSW. Order the title search and planning certificate first, since they cost very little and answer the largest questions.

Where the available area lands somewhere below sixty square metres, that is useful information rather than any kind of defeat. A well planned fifty two square metre dwelling can live better than a poorly planned sixty, and knowing the real number lets a designer allocate it properly from the outset. What does not work is designing to sixty and trimming afterwards, because the rooms that get cut are rarely the ones you would have chosen to lose. Designers work to smaller areas than that routinely, and the results are frequently excellent when the constraint is known early.

Checking a Plan Yourself

You can verify a builder's area claim in about ten minutes and it is worth doing on every plan you are shown. Take the room dimensions from the drawing, multiply each pair, add the rooms together with the hallway included, and compare the result against the stated figure. A calculator and five minutes is the whole exercise. Where your total and their total differ, the difference is either circulation they have not listed or an outdoor area they have excluded, and both are worth asking about. Do it on every plan you are shown, including the ones you like, and compare against the examples at granny flat floor plans. A calculator and the room dimensions are all it takes.

Watch carefully for what the drawing labels a space as, rather than for what it actually measures. A space marked as a store, a nook, a mudroom or a covered terrace still occupies physical area, and whether it counts is a question about its construction rather than its name. Reading a plan by its labels is how households end up believing a seventy square metre building is a sixty square metre one. Names written on a plan describe an intended use, while the area calculation describes the construction itself.

Check whether the stated area is described as internal, external or gross, since those are three different numbers for the same building. A quote stating sixty square metres internal and a control measuring externally are not describing the same thing, and the gap on a dwelling this size is around three square metres. Ask which basis the stated figure has been calculated on, and whether that matches the basis your certifier will actually apply. A builder's quote and a planning control working from different bases are simply not describing the same building at all.

Where a plan is close to the limit, ask for it to be confirmed by the certifier before documentation proceeds. Being within a square metre of a cap is an uncomfortable place to be, because minor changes during documentation can push a compliant plan over. A concept level check at $300 to $800 removes that risk for a fraction of what a late redraw costs. A margin of two or three square metres is a comfortable position and no margin at all is not. Documentation almost always shifts something slightly, and a proposal drawn right to the limit has nowhere to put it.

Keep the annotated plan filed with the rest of your project documents once the area has been confirmed. It becomes the reference point if a builder proposes a change during construction, and it is the document that answers the question quickly rather than reopening the whole calculation. Building work that departs from what was certified creates a problem at occupation certificate stage rather than at the time it is built. Store it digitally as well, since these documents matter years later at sale.

Designing to a Capped Area

Designing to a cap is a different exercise from designing to a budget and it rewards a different order of decisions. With a fixed area, every square metre added to one room is taken from another, so the useful first step is deciding what matters most to the household rather than what would be nice to include. Designers who ask that question before drawing produce better outcomes than those who start with a plan and adjust. Decide the order of importance before you sit down with a designer, not while you are there.

Efficiency in the plan is where the real gains sit. Grouping the wet areas so plumbing runs short, keeping circulation to a minimum, using a wall for two purposes and placing storage where it also provides acoustic separation all deliver more usable dwelling at the same measured area. None of that costs anything beyond thought at the drawing stage. The difference between an efficient and an inefficient plan at sixty square metres is close to a whole room, which is worth more than most of the choices households agonise over. Compare two plans at the same area and the difference in usable space becomes obvious immediately.

Volume is the free dimension because ceiling height does not count toward floor area. A raked ceiling over the living area, higher windows or a clerestory bring light and apparent space at modest cost while leaving the measured figure untouched, which is why the answer to a tight plan is frequently upward rather than outward. This is the single most effective move available to a designer working under a cap and it is underused. Check what ceiling height the price assumes and what raising it would cost.

Covered outdoor space extends the dwelling in a way no internal rearrangement can, provided it is configured so that it does not consume the area you are trying to protect. An open sided roof over a paved terrace, positioned to catch morning rather than afternoon sun, adds a room in practice while remaining outside the calculation in many configurations. It also gives an occupant somewhere to sit that is unmistakably theirs. Getting the configuration confirmed is the whole trick, and design choices are gathered under granny flat designs. Which way it looks decides everything, because nobody sits on a terrace that bakes from two o'clock. Getting the configuration confirmed before it is drawn is the whole trick.

Storage deserves protecting rather than sacrificing, and it is the first thing cut when a plan runs over. A dwelling with nowhere to put a vacuum cleaner, a suitcase or seasonal clothing frustrates its occupants daily, and joinery is far cheaper built in than added later. Where the area genuinely will not stretch, a shed elsewhere in the yard solves the bulky items without touching the measured figure. Have the storage drawn on the plan rather than promised in conversation. Joinery is considerably cheaper built in during construction than added after handover.

Attached or Detached

A secondary dwelling attached to the existing house is assessed differently from a detached one, and the distinction matters more than most households expect. Where the two buildings share a wall, questions arise about fire separation, acoustic performance, how the dwellings are serviced and whether the arrangement is treated as a secondary dwelling or as an alteration to the existing house. The answers change the approval pathway rather than merely the detail. Ask a certifier which category your concept falls into before any design work begins.

On a constrained block an attached addition is frequently the workable answer where a detached dwelling will not fit. Sharing a wall removes the need for a setback between the two buildings, uses the existing services more directly and can be less demanding on site coverage than a separate structure with its own path and surrounds. Acoustic separation between the two dwellings becomes the detail worth spending money on. The trade is privacy, which matters a great deal to some households and very little to others.

Conversions of existing structures sit in a third category again. Turning an attached garage, an under house area or an existing rumpus into a self contained dwelling raises questions about whether the resulting space meets habitable room requirements for ceiling height, light, ventilation and damp, and about how the lost parking or storage is replaced. Costs and constraints for these routes are covered at granny flat additions. Ceiling height in an existing garage is the constraint that most often ends a conversion. Replacing the lost parking or storage is a question worth answering before committing.

Whichever configuration is being considered, the floor area question needs asking again rather than assumed to carry across. An attached dwelling may be measured differently, may interact with the existing dwelling's own floor area, and may be subject to controls that do not apply to a detached building. Establish the position for the specific configuration you intend rather than the one you read about. Nothing about the calculation carries across automatically between configurations.

Get the pathway confirmed before design in every case. Whether a proposal is a secondary dwelling, an addition or an alteration determines which controls apply, and that determination is made on the facts of the proposal rather than on what you call it. A certifier or planner will answer this quickly for a specific concept and slowly for a vague one. Turn up with something drawn, since staff cannot comment usefully on a verbal idea.

What Drives the Price

At a fixed floor area, specification does more to the price than size does. Two sixty square metre dwellings can differ by forty thousand dollars on the kitchen, bathroom, flooring, glazing and cabinetry alone, and none of that shows in the area figure. This is why comparing builders on a rate per square metre tells you very little unless the specification behind each rate is the same. Establish the standard included on each item rather than accepting a general description of quality.

Ground conditions move the total more than anything you choose to put on top of it. The soil grading sets the footing type, a fall brings cut, fill and retaining, and rock makes an ordinary dig expensive. The grading system comes from the residential slabs and footings standard published by Standards Australia, and that report belongs in hand before the design is locked. Twenty thousand dollars can separate two neighbours on ground conditions alone. Commission the soil report before the design is finalised rather than after.

Plan shape affects cost independently of area, which surprises households comparing two designs of the same size. A simple rectangle is cheaper to build than an L shape or a plan with multiple corners, because every corner adds framing, cladding, flashing and labour. Working to both an area cap and a budget usually means keeping the footprint simple and spend the saving on the interior. Roof form follows the same logic, since a simple gable costs less than a complex arrangement.

Documentation costs vary according to whether the design is standard or drawn for your block. An established plan adapted to your site costs less than one developed from a blank sheet, and both are legitimate. Where your permissible area is unusual, a bespoke design is frequently the better value because a standard plan trimmed to fit rarely trims well. Establish whether changes mid process are charged extra.

Late changes are the expensive category and area failures are the most common cause of them. A redraw at $600 to $2,000 is only the visible part, since selections, pricing, engineering and the builder's programme all move with it. Confirming the counted area at concept stage removes the largest single cause, and equivalent build pricing appears under two bedroom granny flat costs. A start date held for you can slip a month or more once a redraw begins.

Floor Area Across Sydney

Reaching sixty square metres is a question about your block rather than your budget across much of Sydney, and the answer varies enormously by subdivision era. Post war and newer estates generally have coverage and landscaped area to spare, while nineteenth and early twentieth century subdivisions frequently do not, and the difference between two suburbs can be the difference between a full sixty and forty five. Measuring what already exists on the property is the step most households skip, and it is set out under granny flat rules. When the land was carved up predicts this better than the suburb name.

Across the western and north western growth corridors the floor area is usually available and site coverage becomes the operative limit instead. Those blocks commonly carry a large house, a double garage, a wide driveway and substantial paving, and the coverage already consumed can leave less than the area suggests. Measuring what exists before designing is the step that avoids the surprise. Photograph the property from above using an online map as a starting point for that exercise.

In the inner and eastern suburbs the constraint is usually absolute rather than a matter of allocation. Small lots with generous existing dwellings frequently permit a secondary dwelling well under sixty square metres or none at all, and households in those areas should establish the real number before looking at any plan. An attached addition is often the better proposition there. Conservation area controls blanket much of that territory and belong in the early checks.

Floor Area in Regional NSW

Outside the metropolitan area the figure is rarely difficult to reach at all, which shifts the question from whether you can build to sixty square metres toward whether you actually should. Households there often find the better dwelling is a smaller one with more spent on the finish. Larger blocks mean coverage and landscaped area seldom bind, so the cap itself becomes the operative limit and the design conversation is about allocation rather than availability. That is a more comfortable position to design from, and it widens the range of granny flat designs genuinely open to you.

Rural zoned land is the exception and the provisions there differ from residential areas in ways that catch people out. Rural land runs on its own set of provisions, with lot size thresholds at another scale altogether and extra questions about where the second dwelling sits in relation to the first. Assuming residential provisions apply because the property has a house on it is a common and expensive error. Someone who works with rural zonings regularly will answer this faster than a general enquiry will.

Where area is not the binding constraint, the temptation is to build larger than the household needs. A dwelling sized to its occupants, with the area concentrated in the rooms they use, generally serves better than one stretched to a limit because the limit was available. Extra area also carries extra construction cost, so it should earn its place rather than being taken by default. Heating, cooling and cleaning a larger dwelling also cost more every year it stands.

Onsite wastewater capacity operates as a practical limit on unsewered properties and it is driven by bedroom count rather than floor area. A council assesses whether the existing system can accommodate the expected occupancy of a second dwelling, and a larger dwelling with more bedrooms is assessed for more people. That assessment belongs early, since a poor result changes the project rather than the plan. Councils generally want that assessed and written up by someone qualified to do it.

Storage is the element sixty square metres punishes hardest and the one households notice within a fortnight of moving in. A linen cupboard, a broom cupboard and somewhere for a vacuum cleaner occupy floor area that a plan drawn to maximise living space frequently surrenders first. Built in robes in both bedrooms are usually non negotiable, and a shallow cupboard in the hallway costs very little while solving a problem that otherwise ends with boxes stacked in a corner. Ask where each of those items will live before approving a layout.

What to Look Out For

Do not treat sixty square metres as your entitlement. It is a maximum rather than an entitlement, the figure itself has been amended more than once over the years, and site coverage, landscaped area and setbacks can all bind before it ever does. Establish the permissible area on your specific property with your council or a registered certifier before commissioning any design, since a written assessment costs a fraction of a redraw. The figure has changed before and may change again, so confirm it rather than relying on any published source including granny flats in NSW.

Ask what counts toward the figure before a design is drawn rather than after. Covered alfrescos, porches, external storage and carports may be counted, partly counted or excluded depending on how each is configured, and the same twelve square metre alfresco can sit inside or outside your total. Have the designer annotate the concept plan itself, showing clearly which areas have been counted and which have not, with a stated total. This single question prevents the most common and most expensive failure on these projects.

Check the basis of any stated figure carefully, since internal, external and gross areas are three quite different numbers describing the same building. Ask which one a builder means before you compare their quote against anybody else's. The gap between measuring inside and outside the walls approaches three square metres on a dwelling this size, which is enough to move a compliant plan over the line. Confirm the basis matches the one the certifier will apply.

Be wary of a plan sitting within a square metre of the limit. Minor adjustments during documentation are normal and a proposal with no margin cannot absorb them, so what was compliant at concept stage can fail at certification. Establish what would have to change if the certifier measured it differently. A comfortable margin of two or three square metres is worth more than a slightly larger room you may not be allowed to keep.

Measure the plan yourself rather than relying on the label. Multiply the room dimensions, add them with the hallway included, and compare against the stated figure, then ask about any difference. Workmanship guarantees are enforced by the ACCC, while NCAT is where a dispute with a builder is heard. It takes ten minutes and requires nothing more than a calculator.

What to Look for in a Quote in NSW

A design or build quote should state the counted area and the basis it is measured on. It should give the internal floor area, list each room with its dimensions, show circulation separately, state whether any covered outdoor area is included in or excluded from the total, name the basis as internal or external, confirm who has verified the figure, and identify what would change if the area were found to be measured differently. The measurement basis and the treatment of outdoor areas are the two items most often unstated. Ask for the room schedule as a table rather than reading dimensions off a drawing. Two quotes on different bases cannot be compared at all.

Give every designer the same starting information about your block. Provide the address with lot and deposited plan numbers, the planning certificate if obtained, a survey if you have one, a list of everything already on the property including the house, garage, shed, pool, paving and driveway, and the permissible area if it has been assessed. Build the package once and forward the same one to everybody rather than retelling it. Designers work from constraints, and a design produced without them will need redrawing.

A designer who asks about your existing site coverage before your room preferences understands the problem. Someone who wants to know what is already built on the block, what is paved, where the setbacks fall and what area has actually been assessed as available is establishing the envelope before designing inside it. One who opens with a catalogue of plans is showing you buildings rather than solving your constraint. Ask what they would do if the assessed area came back at fifty rather than sixty. Establishing the envelope before designing inside it is the correct order.

Settle the permissible area, the counting basis and the outdoor treatment before documentation begins. Get the written assessment, confirm what counts with the certifier, have the concept annotated with the counted total, and keep that document with your project file. Licences for building work are issued by NSW Fair Trading, and national operators are gathered on the granny flat builders hub. Keep every assessment, plan and piece of correspondence together in one file.