Quick Answer
A full second storey extension in Sydney typically starts from around $350,000 and rises with size, finish and complexity. A roof lift extension, which raises your existing roof to create an upper level, is often a more affordable way to gain the same rooms — where your home suits it.
In This Guide
Cost by Type of Upper-Level Addition
Roof Lift Extension
Raises and re-pitches your existing roof to create habitable upper-level rooms. Because it reuses much of your structure, it can deliver an extra level for less than a full new storey — when your home is suitable.
Full Second Storey Extension
From ~$350,000A complete new upper floor built over your existing home, adding multiple bedrooms, a bathroom and often a living zone. The most transformative option, and priced accordingly.
Not sure which suits your home? Our attic conversion vs second storey comparison weighs cost, disruption and outcome.
Factors That Affect Cost
Second storey pricing varies more than most projects. The biggest drivers are:
Size & Number of Rooms
More floor area and more rooms — especially bathrooms — increase both materials and trades.
Existing Structure
Your ground-floor walls and footings must carry the new level. Reinforcement, where needed, is a major cost factor.
Roof Lift vs New Build
Reusing your roof structure via a roof lift is generally cheaper than demolishing and building a full new storey.
Finish Level & Services
Premium finishes, ensuites, heating and cooling, and high-end joinery all lift the final figure.
Return on Investment
A second storey adds substantial legal floor area and bedrooms — the features Sydney buyers value most — while keeping your land, garden and location. For families who love where they live, building up is frequently cheaper than the stamp duty, agent fees and price gap involved in moving to a larger home.
In many Sydney suburbs, a well-designed upper level can add value well beyond a comparable ground-floor extension, because it doesn't consume backyard space.
Getting an Accurate Quote
Because second storeys depend so heavily on your existing structure, an on-site assessment is essential for accurate pricing. Our free, no-obligation inspection covers:
- Whether your home suits a roof lift or a full new storey
- The structural works your ground floor will need
- Room layout options for the new level
- Approval pathway and realistic timeline
- A detailed written quote
Get Your Free Quote
Book a free on-site inspection and get an accurate quote for your second storey extension.
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