Home Extensions · Glenhaven NSW 2156
Home extensions in Glenhaven, done properly.
Home extensions in Glenhaven by a licensed builder, on lots from 700 square metres to 2 hectares and across two council areas. 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 on a bigger block
Making a Glenhaven home bigger.
Strava Group builds house extensions in Glenhaven: family rooms out the back, extra bedrooms, parent retreats and covered outdoor living. Minimum lot sizes in Glenhaven run from 700 square metres up to 2 hectares depending on the zone, so many homes have the land for a generous ground floor addition. The work is in the detail: which council you are in, whether the lot is bushfire prone, and how the new floor meets the old.
Extensions we build for Glenhaven homes:
- Family room and kitchen extensions
- Parent retreats and guest suites
- Extra bedrooms and bathrooms
- Covered outdoor living and entertaining
- Construction to the assessed BAL
- Extensions linking split levels
- Home offices with their own entry
- Roof and cladding matched to the house
If the size is right and the layout is the problem, see home renovations in Glenhaven. For more space without giving up garden, see second storey additions.
Glenhaven blocks give an extension room to breathe. The new family room can face the yard and the sun, with an outdoor area off it, and you still keep the garden that brought you here.
Quick Answer
Most home extensions in Glenhaven 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. Bushfire rated construction, tree protection around the footings and adding an ensuite are the main cost drivers here.
Local knowledge
What we know about extending in Glenhaven.
Two councils, a wide range of lot sizes and bushland edges make Glenhaven worth checking carefully. This is our list.
Which council
Glenhaven is split between The Hills Shire Council and Hornsby Shire Council, with the eastern end zoned RU2 under the Hornsby LEP 2013. The two councils have different development controls, so setbacks, site coverage and approval steps can change from one end of the suburb to the other. See The Hills Shire Council, Hornsby Shire Council and the NSW Planning Portal.
Lot sizes
Minimum lot sizes range from 700 square metres to 2 hectares depending on the zone. On the larger lots, bushfire, tree and setback controls are what usually limit an extension. On the smaller ones, the landscaped area rules usually decide how far it can go.
Bushfire
Lots near bushland in Glenhaven are mapped bushfire prone. An extension there gets a Bushfire Attack Level assessment and is built to the rating, which affects glazing, cladding, decking and gutter protection. At BAL-40 and Flame Zone, Complying Development is off the table and the job goes to a DA.
Split levels
Where a home is split level, the extension has to land on the right level and connect cleanly to the rooms around it. We plan the steps, landings and ceiling heights at design stage so the new space reads as part of the house.
Trees
Bigger blocks usually come with bigger trees. Removing or pruning a protected tree needs council approval, and roots near the new footings can change the footing design. We check the trees around the extension footprint before drawing it.
Services on larger lots
On the larger lots, sewer, stormwater and power can run a long way from the house. If your property runs on an on-site wastewater system, adding a bathroom can mean upgrading it. We confirm what the property is connected to and trace the lines early, since moving a buried service mid-build is expensive.
Start here
Tell us about your Glenhaven 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 Glenhaven 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 Glenhaven.
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 Glenhaven most projects sit in the middle of the band. Bushfire rated construction near bushland, tree work and the size of the family room lift it. How much of the existing structure has to change decides the rest, especially on split level homes where the new floor meets more than one level.
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
Glenhaven 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 Glenhaven.
We build extensions across The Hills and Hornsby and the surrounding suburbs. Select a suburb for local council information and what extensions there typically cost.
The Hills and Hornsby
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 Glenhaven? We also build second storey additions and home renovations in Glenhaven.
Extend your Glenhaven 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 Glenhaven
Other Strava Group services in Glenhaven
Each page covers the local council, the homes we see in Glenhaven and what that kind of project typically costs.