What we do · Our specialty
Home extensions & second-storey additions.Sydney extension builder — ground-floor, rear and upper-level additions by a licensed builder
Why extensions are different
The hard part of an extension is the join.
R&Q Interiors is a licensed Sydney builder (NSW Builder Licence 378767C) that specialises in extensions and alterations — the work where new structure has to meet an existing house and read as if it was always there.
A new home on a clear site is a known quantity. An extension is not: you are building around existing footings, existing services and often a family still living in the house, and some of what you are dealing with only reveals itself once a wall is open. It takes a builder who has done it many times to price it honestly and sequence it properly.
We build extensions across Sydney. Our completed projects sit in Silverwater, Strathfield, Rhodes, North Ryde, Willoughby and Castle Hill, and we work throughout the corridor from the Inner West through Auburn, Lidcombe and Granville to Parramatta, as well as the Hills and the Lower North Shore.
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Extensions · What we build Three ways to add space without moving.
Ground-floor, second-storey, or rework the plan.
R&Q Interiors builds every form a Sydney extension takes — and because we also build whole-home renovations and new homes, we will tell you honestly when a different path suits your house better.
- Ground-floor and rear extensions — open the house to the garden, add living space, re-plan the kitchen around it
- Second-storey and upper-level additions — bedrooms and a parents’ retreat above, engineered on the existing structure
- Structural alterations — remove walls under engineered beams, open the plan, improve light and flow
- DA / CDC approvals coordinated with your architect, engineer and certifier
- Fixed-scope contract, set programme, written weekly updates
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Before you enquire
What moves the price of an extension?
R&Q Interiors quotes extensions per project after a site visit, because the same floor area can cost very different amounts depending on the house it is attached to. These are the variables that move the number most.
Structure Ground floor or second storey
A second storey has to be carried by the existing footings and walls. That usually means an engineer’s inspection first, and sometimes underpinning or new load paths through the house below — work that is invisible in the finished room but real in the price.
Services Whether wet points move
Relocating a kitchen or bathroom means new waste and water runs, and often floor levels change to get the falls right. Switchboard capacity is the other common surprise: an older board frequently needs upgrading before new circuits can be added.
Site Access, ground and excavation
Whether a machine can reach the rear of the block, what the soil does when it is opened up, and how far material has to be carried all change the labour on the same drawing. Sloping sites and rock cost more than flat ones.
Matching Joining new work to old
Matching brickwork, roof profile, window style and floor level so the addition does not read as bolted on is where most of the craft sits — and it is the part that separates a considered extension from a cheap one.
Can your house take a second storey?
Not every house can, and the answer is structural rather than architectural. What decides it: the depth and condition of the existing footings; whether the ground-floor walls are load-bearing and continuous enough to carry a new floor; the roof framing and whether it can be removed and rebuilt; and the planning controls on your block — height limits, setbacks and floor space ratio. The sequence that saves money is an engineer looking at the existing structure before design money is spent, not after.
Good to know
Questions Sydney homeowners ask about extensions.
How much does a home extension cost in Sydney?
There is no honest per-square-metre rate, because the same floor area can cost very different amounts depending on the house it is attached to. The variables that move the number most: whether the addition is ground-floor or second-storey (footings and load paths), whether a kitchen or bathroom relocates (new waste and water runs), site access and ground conditions, and how much matching of brick, roof and floor level the join demands. R&Q Interiors gives a preliminary estimate and outline scope at no charge before you invest in full design, so you know whether the project and the budget line up.
Do I need a DA for a home extension, or can it be approved as a CDC?
It depends on the design and the block, not on the builder. A CDC — a Complying Development Certificate, assessed by a private certifier and measured in weeks — is available when the extension meets the standard criteria in the NSW Codes SEPP. A council DA applies when it does not: a heritage or conservation-area overlay, flood-prone or bushfire-mapped land, or exceeding the height, setback or landscaped-area limits are the common triggers, and a DA is measured in months. R&Q Interiors confirms which pathway applies at the first site consult, before you spend money on design.
How long does a home extension take to build?
Two clocks run on an extension. Design and approvals come first — weeks for a CDC once documentation is complete, months for a council DA. Construction time then varies with the scope: a second-storey addition is a longer programme than a rear extension because the roof and structure of the existing house are involved. R&Q Interiors sets the programme in the contract before work starts and sends a written progress update every week, so you always know where the job stands.
Will the new part of the house match the existing one?
Making the addition read as part of the original house is most of the craft in extension work, and it is the reason R&Q Interiors calls extensions its specialty. Matching means the brickwork, the roof profile, the window style and the floor levels — and inside, the flow between old rooms and new. An extension that is merely attached reads as bolted on from the street and from the hallway; one that is integrated does not.
Can we live in the house while the extension is built?
Often, and the shape of the extension decides it. A ground-floor or rear extension can usually be built largely outside the existing envelope, with the break-through into the old house sealed and staged late in the programme. A second-storey addition is more intrusive because the existing roof and structure are involved. R&Q Interiors builds inside occupied Sydney homes regularly and tells you at the estimate stage which phases will be liveable — before you commit, not after the deposit.
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R&Q Interiors (R & Q Pty Ltd) has been building in Sydney since 2017 — NSW Builder Licence 378767C, HIA member. Every residential project over $20,000 (including GST) is covered under the NSW Home Building Compensation Fund before work starts, and carries the statutory warranty: 6 years for major defects, 2 years for other work.
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