Home Extensions · Marrickville NSW 2204
Home extensions in Marrickville, done properly.
Rear and side house extensions for Marrickville 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 Marrickville 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 Marrickville.
- 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
More room at the back of a Marrickville home.
Strava Group builds home extensions in Marrickville: rear extensions, side returns and whole-of-back transformations that open the house to the yard. Marrickville is a mix of Federation semis and cottages, Victorian terraces near the station, interwar bungalows on the wider streets and a good stock of post-war brick. Much of it sits in heritage conservation areas. On the semis and terraces the extension is always a custom project built around a party wall. On the freestanding homes it is the classic brief: keep the front, rebuild the back.
In Marrickville 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 Marrickville.
Local knowledge
What we know about extending in Marrickville.
Every suburb builds a little differently. This is what matters when you are extending a Marrickville home.
Council
Marrickville is in the Inner West Council area under the Inner West Local Environmental Plan 2022. A large part of the suburb sits inside heritage conservation areas, which removes the Complying Development pathway and means most extensions go through a Development Application. A rear extension that sits behind the original roofline and is not visible from the street is well supported by the controls. Some streets near the airport carry aircraft noise controls that affect glazing and insulation. We confirm the pathway for your property before quoting. Current planning controls are published by Inner West Council and on the NSW Planning Portal.
Housing stock
Federation semis and cottages across most of the suburb, Victorian terraces near Marrickville and Sydenham stations, Californian bungalows on the wider streets toward Dulwich Hill, and post-war brick homes built by the families who settled here after the war. Many carry a lean-to or fibro sunroom tacked onto the back decades ago. Those earlier additions usually come off and are replaced with something engineered.
Structure
Semis and terraces share a party wall, and the extension is designed around it: the new structure is tied to the existing masonry without loading the shared wall beyond what it was built for, and the neighbour is kept informed throughout. Cutting openings into old double brick rear walls needs engineered lintels and careful propping. The post-war brick homes, often full brick on a slab, extend more simply once the load path is engineered.
Yard and block
Blocks are mostly 250 to 500 square metres, with semis on the narrow end and the bungalows and post-war homes on the wider end. Side access is the first thing we check: semis often have access down one side only, and where there is none materials come through the house and the programme changes. A rear extension across the full width of the block, with a usable yard kept beyond it, is the usual move.
Services and ground
Marrickville sits on shale derived clay soils that move with moisture, with alluvial ground on the low side toward the Cooks River that needs its own footing design. The footings under a 1910s house were never engineered, so new footings are designed for the site and detailed against the old ones so the extension does not settle away from the house or pull on a party wall. Old sewer and stormwater lines often run along the rear boundary and are located before design starts.
Value
Marrickville has become one of the most sought after suburbs in the inner west, with the Metro, the station, the Addison Road and Illawarra Road strips and the creative scene holding demand. Buyers pay a premium for a semi or cottage with a properly built modern rear, and an extension that keeps the Federation front and opens the back to the yard is one of the safest improvements you can make.
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 Marrickville 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 on a semi it matters twice over because the party wall has to be protected as well.
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 Marrickville.
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 Marrickville the smaller blocks and heritage controls tend to keep projects in the lower and middle part of the band, but party walls, narrow access and the work involved in taking off an earlier lean-to can add to it. Semi and terrace extensions are custom builds quoted on their own terms. How much of the existing structure has to change is usually the largest single factor, followed by access and wet areas.
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 the inner west. Select a suburb for local council information and what extensions there typically cost. Looking for a different service in Marrickville? We also build second storey additions in Marrickville and home renovations in Marrickville.
Home extensions near Marrickville.
Inner West
Good to know
Marrickville extension questions.
How much does a home extension cost in Marrickville?
Do I need council approval for an extension in Marrickville?
How long does a home extension take to build in Marrickville?
Can I live at home during the extension?
Should I extend out or add a second storey in Marrickville?
Can you extend a semi without affecting the neighbour?
How will I know what is happening during my extension?
Are you licensed and insured?
Extend your Marrickville 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.
