Home Extensions · Cheltenham NSW 2119
Home extensions in Cheltenham, done properly.
Rear and side house extensions for Cheltenham homes by a licensed extension builder. 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.
Start here
Tell us about your Cheltenham home.
No sales pitch, no obligation. Here is exactly what happens when you enquire:
- 1Answer a few quick questions. One at a time, takes about two minutes, so the first conversation is about your project rather than the basics.
- 2We call you within 24 to 48 business hours. A builder, not a salesperson. Then we walk your home and yard with you on site in Cheltenham.
- 3You receive a written, itemised estimate. Real numbers for your home. If the project does not stack up, we tell you that too.
From our clients
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.”
Extending out, not up
Extending a Cheltenham home among the trees.
Strava Group builds home extensions in Cheltenham: rear additions, side extensions and whole-of-back transformations that open the house to the garden. Cheltenham is small, quiet and almost entirely inside the Beecroft Cheltenham Heritage Conservation Area, with large treed blocks running down toward the Lane Cove National Park. The houses were built to be seen from the street, which is why the best extensions keep the front exactly as it is and do all their work at the back.
In Cheltenham we regularly deliver:
- Rear extensions and additions
- Side extensions on wider blocks
- Open plan kitchen, dining and living
- Alfresco and indoor-outdoor connections
- New master suites and family rooms
- Laundries, mudrooms and storage done properly
- Structural openings between old and new
- Exterior upgrades to tie old and new together
Thinking about going up instead? That is a different build with different engineering, and we do that too: see second storey additions in Cheltenham.
Local knowledge
What we know about extending in Cheltenham.
Every suburb builds a little differently. This is what matters when you are extending a Cheltenham home.
Council
Cheltenham is in the Hornsby Shire Council area under the Hornsby Local Environmental Plan 2013, and almost the whole suburb sits inside the Beecroft Cheltenham Heritage Conservation Area. That removes the Complying Development pathway, so extensions go through a Development Application with a heritage assessment. Rear extensions that sit behind the main roofline and keep the street presentation are well supported. We confirm the pathway for your property before quoting. Current planning controls are published by Hornsby Shire Council and on the NSW Planning Portal.
Housing stock
Federation and interwar homes on the older streets near the station, a strong stock of 1950s and 60s brick and weatherboard houses, and some later homes set deep on bush blocks toward the national park. Many have been extended once before, often with a sunroom or family room of uncertain quality. A proper rear extension usually replaces that work rather than adding to it.
Structure
The older Cheltenham homes are double brick or timber framed with weatherboard cladding on brick piers, hardwood floors and framed roofs. Cutting a new opening into an old rear wall needs an engineered lintel and careful propping, and the new floor has to meet the existing suspended timber floor exactly. Weatherboard homes extend well in timber, and the junction is where the flashing has to be done properly.
Yard and block
Blocks in Cheltenham are typically 900 square metres and upward, many of them sloping and most of them treed. The trees are protected under council controls and usually decide where the extension can go. The size of the block means a substantial rear extension is possible while keeping the garden, and on the steeper blocks the extension often steps down the site.
Services and ground
Cheltenham sits on shale derived clay over Hawkesbury sandstone, with the rock close to the surface on the slopes toward the park. Footing design varies across a single block, so the engineering is done for your site, and new footings are detailed against the existing ones so the extension does not settle away from an old house. Absorption trenches and old services on the larger blocks are located before we design.
Value
Cheltenham is tightly held and rarely built out: the conservation area, the trees and the quiet protect its value, and the station and school catchments keep demand steady. Buyers here pay for character houses that have been extended properly at the rear, and a considered extension that keeps the front intact is one of the safest improvements in the suburb.
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 Cheltenham extension we run:
Every new-to-existing junction properly detailed
This is where most extensions crack, leak and part company with the house. It is almost always a detailing shortcut, not settlement. Ours get a proper structural tie, flashing and movement detail.
The existing structure gets rectified, not covered
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 and future cracking is designed out, not painted over.
Footings matched to the ground, not the minimum
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.
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 Cheltenham.
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.
Preliminaries are the costs that exist before a single wall moves: site fencing, temporary services, waste removal, insurances, engineering 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 Cheltenham the large blocks allow substantial extensions, but the heritage process, protected trees and sloping sandstone sites add design and engineering work that pushes projects toward the middle and upper part of the band. How much of the existing structure has to change is usually the largest single factor, followed by wet areas, access around trees and how far footings have to go to find rock.
Every project is quoted properly after a site inspection. These ranges are here so you can decide whether it is worth a conversation.
Nearby We build extensions across Hornsby Shire and the surrounding northern suburbs. Select a suburb for local council information and what extensions there typically cost. Looking for a different service in Cheltenham? We also build second storey additions in Cheltenham and home renovations in Cheltenham.
Home extensions near Cheltenham.
Hornsby and the northern suburbs
Good to know
Cheltenham extension questions.
How much does a home extension cost in Cheltenham?
Do I need council approval for an extension in Cheltenham?
How long does a home extension take to build in Cheltenham?
Can I live at home during the extension?
Should I extend out or add a second storey in Cheltenham?
Will the extension have to match my heritage house?
How will I know what is happening during my extension?
Are you licensed and insured?
Extend your Cheltenham 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.
