Home Extensions · Greystanes NSW 2145
Home extensions in Greystanes, done properly.
Home extensions in Greystanes by a licensed builder, for both the older homes and the newer estate houses. Most extensions run $70,000 to $300,000 depending on size and how much of the existing house has to change, itemised quote, honest programme, one builder from concept to handover.
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Extending, two ways
Two kinds of Greystanes extension.
Strava Group builds house extensions in Greystanes, and the suburb asks for two different approaches. On the older homes, an extension adds space to a house with decades of wear, and the work at the join matters as much as the new room. On the newer estate houses, the structure is younger and the brief is usually a bigger family room, a better kitchen and a proper covered area out the back.
Extensions we build for Greystanes homes:
- Rear family room and kitchen extensions
- Ground floor bedrooms and ensuites
- Replacing old rear additions
- Alfresco areas tied into the roof
- Stepped extensions on sloping lots
- Laundry and storage extensions
- Structural openings in brick walls
- Exterior work to blend old and new
Prefer to keep the yard and go up? See second storey additions. If the house is big enough and it is the kitchen, bathrooms or layout holding you back, see home renovations in Greystanes.
Greystanes has older homes that need their back half rebuilt properly and newer ones that simply need more room. Telling the two apart on the first site visit is what keeps the quote honest.
Quick Answer
Most home extensions in Greystanes run $70,000 to $300,000 depending on size and how much of the existing structure has to change, at roughly $2,500 to $4,500 per square metre for ground floor work, with around $30,000 in preliminaries (design, engineering and council approvals, plus site set-up) on top. The age of the house, a sloping lot and adding a bathroom decide where most Greystanes projects land.
Local knowledge
What we know about extending in Greystanes.
Greystanes covers a wider range of houses and land than most suburbs. These are the things that change an extension here.
Council
Greystanes is in the Cumberland City Council area under the Cumberland Local Environmental Plan 2021. Many detached homes can extend through Complying Development with a private certifier. Heritage items sit in the older eastern end of the suburb, and a property holding one needs a Development Application, as do lots with other site specific controls. See Cumberland City Council and the NSW Planning Portal.
Older homes
The older homes need the most care at the junction. We check the rear wall, roof framing and subfloor where the extension connects, replace damaged timber and test any old sheeting for asbestos before it is cut. The new section is engineered from its own footings and tied in so the two halves move together.
Newer homes
The newer estate homes are usually brick veneer on a slab with sound framing. Extending them is mostly a design exercise: where to open the rear wall, how to carry the roof over the new room and how to keep enough yard. Bricks of this age are easier to match, so the addition can often look original.
Slope and drainage
Some Greystanes streets fall noticeably, and on those lots the new floor may sit above the yard on a stepped slab or a suspended floor. We design the drainage around the extension at the same time, because water trapped against the junction is behind most damp and movement complaints we are called to.
Lot size and access
Lot sizes vary across the suburb. The setback, landscaped area and private open space rules decide how big an extension can be under Complying Development, so we measure your lot against them on the first visit. Where there is no side access for machinery, we plan for smaller equipment and price it in.
Staying put
With Greystanes Shopping Centre inside the suburb and your street already known, moving means paying stamp duty and agent fees before you gain a single square metre. For many families an extension is the cheaper way to get the space while keeping everything else the same.
Start here
Tell us about your Greystanes home.
No sales pitch, no obligation. Here is exactly what happens when you enquire:
One at a time, takes about two minutes, so the first conversation is about your project rather than the basics.
The Strava standard
How we build differently.
An extension lives or dies at the junction between old and new. We build for longevity, and on every Greystanes extension we run:
Every new-to-existing junction properly detailed
This is where most extensions crack, leak and part company with the house, and the cause is almost always a detailing shortcut. Ours get a proper structural tie, flashing and movement detail.
The existing structure gets rectified first
Where the extension meets the house, we screw off and re-brace the adjoining structure, tying new and old together so the whole building moves as one. Future cracking gets designed out at frame stage instead of patched at the paint stage.
Footings engineered for the ground they sit on
New footings are engineered for your soil and detailed against the existing ones, because differential movement between old and new slabs is the classic extension failure, and it matters more on an older house whose original footings were never engineered to modern standards.
Furring channels for a dead flat finish
Where new ceilings and walls run through to existing rooms, furring channels give one level plane across both, so you cannot see where the house ends and the extension begins.
Waterproofing is a documented hold point
New wet areas are inspected and photographed before a single tile goes on, to AS 3740, and new roof-to-old-roof junctions get the same treatment.
Everything photographed before it is covered
You receive the record at handover, so in ten years you know exactly what is behind your walls and under your floor. Want more than photos? We can also capture a full 3D virtual model of the frame, plumbing, wiring and waterproofing before the plasterboard goes on, available as an optional add-on.
Before starting Strava Group, I spent seven years on the tools as a carpenter and five years running sites. The failures I kept seeing in extensions were always at the join: cracked cornices along the old wall line, roofs that leaked where new met old, floors that stepped as slabs settled differently. None of it was illegal. All of it was avoidable. None of this shows up in a finished-room photo. All of it shows up in year seven.
Honest numbers
What a house extension actually costs in Greystanes.
Most builders will not put numbers on a website. We will, because the alternative is wasting your time and ours across three meetings before anyone mentions a figure.
| Item | Typical range |
|---|---|
| Home extension, depending on size and scope | $70k–$300k |
| Ground floor extension work | $2,500–$4,500 /m² |
| Preliminaries, on top of build cost | approx. $30,000 |
Preliminaries are the costs that exist before a single wall moves: design, engineering and council approvals, plus site set-up such as site fencing, temporary services, waste removal, insurances and supervision. They are real, they are unavoidable, and a quote that does not show them separately has either buried them or forgotten them.
In Greystanes the spread is wide. Older homes needing repairs at the join, or a stepped slab on a sloping lot, sit toward the middle of the band, while a straightforward rear room on a newer flat lot can sit lower. Across both, how much of the existing structure has to change remains the biggest single cost driver.
Every project is quoted properly after a site inspection. These ranges are here so you can decide whether it is worth a conversation.
Good to know
Greystanes extension questions.
Rated 5.0 on Google.
We had Strava Group complete major renovation works on our property and were blown away with the quality. The attention to detail and overall finish were amazing.
Great communication, honest work, easy to work with, highly recommend to work with for any new build/renovations. If you are looking to get work done without worrying about shortcuts Strava Group is builder to use.
I highly recommend Strava Group to everyone great workmanship, reliable service, and I couldn’t be happier with the result.
I couldn't be happier with the work from Strava Group. From the beginning, Stav and the team was friendly, honest, and super easy to deal with.
We engaged Strava Group for a home extension and renovation. We are incredibly happy with the service and the results we achieved. From day one Stav and team where always willing to help with any issues we had and we loved that the main focus was as quality and longevity. Highly recommended
Had a great experience with Strava Group. The team was easy to deal with, super professional, and kept me in the loop the whole way through. They really listened to what I wanted and made the whole process feel smooth and stress-free.
Aloona T.
Google review
Orom Gabriel
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Jonathan
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Clara Shabow
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Jonathan Jajo
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Eli Kosso
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Nearby
Home extensions near Greystanes.
We build extensions across the Cumberland area and the surrounding western suburbs. Select a suburb for local council information and what extensions there typically cost.
Cumberland and western Sydney
The Hills District
Hornsby and the Northern Suburbs
Ryde, Hunters Hill and the North Shore
Inner West
Parramatta
Western Sydney
Southern Sydney and St George
Looking for a different service in Greystanes? We also build second storey additions and home renovations in Greystanes.
Extend your Greystanes home properly.
Ready for more room?
Tell us about your property and what you want to add. We respond within 24 to 48 business hours with honest advice and real numbers, no cost, no obligation.
More in Greystanes
Other Strava Group services in Greystanes
Each page covers the local council, the homes we see in Greystanes and what that kind of project typically costs.