Tools
What does it cost to go up?
Size the new floor, count the bedrooms and bathrooms, decide where the stair lands. The range starts from our fixed price second storey packages and shows what each choice adds, with design, engineering and approvals listed separately.
- Anchored to our fixed price packages
- Free acoustic insulation in the subfloor
- Itemised quote to follow
The calculator
Build your second storey estimate
Packages start from $274,000 for the new upper floor works. Move the size and the rooms; the nearest package and your range update together.
Your second storey
Your indicative range
From
To
$351,000 to $414,000
Package prices plus preliminaries: $304k–$378k
Nearest fixed price package
- Essential1 Bed · Living · Ensuitefrom$274,000
- Family3 Beds · Living · 1 Bathfrom$320,000
- Complete3 Beds · Living · 2 Bathsfrom$348,000
Package prices are “from”, GST inclusive, new upper floor works only.
Included free: acoustic insulation in the subfloor
Batts between the new floor joists, under yellow tongue flooring, for a quieter upstairs. Hebel or Nexcore flooring is available as an upgrade where the existing structure can take the additional weight.
How it adds up
- New upper floor works60 m², internal staircase allowance and one bathroom (nearest package: Family, from $320,000)
- $322k–$384k
- PreliminariesDesign, engineering and council approvals, plus site set-up, quoted separately
- $30,000
What is driving it
- Size above 40 m²+$48k–$57k
Indicative range only. A site visit and an itemised quote confirm the real price. Every Strava Group quote lists inclusions, exclusions and preliminaries separately, with any provisional sums shown openly.
Honest numbers
How this estimate is worked out.
The starting point is the package price nearest your floor size, so the number is anchored to a price we actually build for. Larger floors, extra bathrooms, ground floor changes for the stair and finish level are added on top, then preliminaries.
Package prices are “from”, GST inclusive and cover the new upper floor works only.
| Figure | What it covers | Where it comes from |
|---|---|---|
| from $274,000Essential: approx. 40 to 45m², 1 bed, living, ensuite. | Essential: approx. 40 to 45m², 1 bed, living, ensuite. | Second storey additions |
| from $320,000Family: approx. 55 to 65m², 3 beds, living, 1 bath. | Family: approx. 55 to 65m², 3 beds, living, 1 bath. | Second storey additions |
| from $348,000Complete: approx. 70m² and above, 3 beds, living, 2 baths. | Complete: approx. 70m² and above, 3 beds, living, 2 baths. | Second storey additions |
| $270,000–$400,000Custom second storeys priced against your plans. The spread between those two figures sets the gap between Standard and Premium finishes. | Custom second storeys priced against your plans. The spread between those two figures sets the gap between Standard and Premium finishes. | Second storey additions |
| $3,500–$5,500 /m²Work at first floor level. Floor area beyond the Complete package is added at the start of this band. | Work at first floor level. Floor area beyond the Complete package is added at the start of this band. | Second storey additions |
| approx. $30,000Preliminaries: design, engineering and council approvals, plus site set-up, quoted separately. | Preliminaries: design, engineering and council approvals, plus site set-up, quoted separately. | Second storey additions |
Before anything is designed
What moves a second storey price.
Your house was built to hold up one storey. A second floor roughly doubles what the foundations carry, which is why the first question is structural.
- 01
What is under the house
On plenty of Sydney blocks the soil moves with the weather and footings need strengthening first. An engineer checks before we give you a fixed price. - 02
Walls and frame
Double brick, brick veneer and timber frame each carry a new floor differently. Steel beams, extra bracing or footing upgrades are quoted separately, clearly, before you commit. - 03
Where the stair lands
A stair that fits a hallway uses the standard allowance. One that needs walls moved downstairs adds ground floor work. - 04
Bathrooms upstairs
Essential includes an ensuite, Family one bathroom and Complete two. Each wet area carries more trades per square metre than any other room. - 05
Council controls
Height limits and your neighbours’ winter sunlight often decide ceiling heights and roof shape. A DA is the usual path, though some additions can use complying development. - 06
Getting a crane in
Narrow driveways, overhead power lines and steep blocks all add cost. Better to know at the start than in week three.
Clear scope
What is in the range, and what is not.
Included in the range
- New upper floor works at your size and finish level: structural framing to engineer’s details, roof, cladding, windows, insulation, plasterboard, doors, painting
- Internal staircase allowance
- Subfloor acoustic insulation included free while the current offer runs: batts between the new floor joists, under yellow tongue flooring
- Extra upstairs bathrooms and stair-related ground floor changes, if you selected them
- Preliminaries of about $30,000: design, engineering and approvals, plus site set-up
Not in the range
- Structural steel, footing, pier or foundation upgrades, or extra bracing to the existing house
- Ground floor renovations, new downstairs kitchens, bathrooms or laundries
- Existing termite, rot, water or defect repairs; electrical mains, switchboard or stormwater upgrades
- Feature or premium staircase upgrades
- Hebel or Nexcore flooring: available as an upgrade where the existing structure can take the additional weight
Construction runs around 12 to 24 weeks depending on size and complexity. See the full package inclusions on second storey additions in Sydney, or plan the stages with the project timeline planner.
Keep planning
More tools
- 01
Home Extension Cost Calculator
Size, rooms and finish in, an honest price range out, with what is driving it.
Size · type · kitchen & bathroom · finish
Open the tool - 03
Renovation Cost Calculator
Pick the rooms, tell us the house, see where a renovation budget really goes.
Rooms · house age · structural walls · finish
Open the tool - 04
Extend or Build Up?
Extend at ground level or add a level: cost, time and yard compared for the same space.
Space to add · yard size · finish
Open the tool - 05
Project Timeline Planner
From first call to handover, stage by stage, with the month you could move in.
Project type · approval pathway
Open the tool
Check if your home can carry a second storey.
A builder walks your home with you, then prepares a written, itemised estimate: inclusions, exclusions and preliminaries listed separately. We respond within 24 to 48 business hours. No cost, no obligation.