Skip to content

Built Once. Built Right.

New timber staircase in a renovated home

Second Storey Additions · Sydney

Add bedrooms, bathrooms & living space, without moving.

Fixed price second storey additions across Sydney, from $274,000. Built to our Above Standard Carpentry Specification, with acoustic insulation in the subfloor included free on early projects.

Master Builders Association NSW member
NSW Licensed Builder
487370C

5.0 Google Rating

Sydney wide5.0 Google RatingNSW Builder’s Licence 487370CFixed price scopeClear inclusions & exclusions0450 605 080

Space without moving

More room, without leaving your street.

Outgrowing your home does not mean you need to move. You love your street, your neighbours, the school run. What you do not love is running out of space. Moving means stamp duty, agent fees and starting over somewhere that may never feel like home.

On a million dollar purchase, stamp duty alone runs to roughly $40,000 before you have paid an agent, a conveyancer or a removalist. For many families, the cost of changing suburbs exceeds the cost of the addition that would have solved the problem.

A second storey addition lets you stay exactly where you are and build the space you need. Extra bedrooms, a second bathroom, a private master retreat or an upstairs living zone, without giving up a metre of backyard. You build up, not out.

Strava Group builds second storey additions across 26 Sydney suburbs. About us.

Same land. Same suburb. Same address. A whole new upstairs.
New staircase with protected treads, plasterboard set on the walls around it
★

Limited time offer

Free acoustic insulation in the subfloor on early packages. A quieter floor between levels, at no extra cost.

Choose your package

Three fixed price starting points.

All prices are “from”, GST inclusive, and apply to the new upper floor works only. Every package includes acoustic insulation in the subfloor while the current offer runs.

Essential

Approx. 40 to 45m²

From$274,000

1 Bed · Living · Ensuite

  • New upper level with 1 bedroom
  • Living or retreat area
  • Ensuite
  • Internal staircase allowance
  • Subfloor acoustic insulation included

Best for: smaller additions, a parents’ or teenager’s space.

Complete

Approx. 70m² and above

From$348,000

3 Beds · Living · 2 Baths

  • 3 bedrooms upstairs
  • 1 living area
  • 2 bathrooms
  • Internal staircase
  • Subfloor acoustic insulation included

Best for: a major, whole family transformation.

Not a package job?

Custom second storey additions.

The three packages cover the shapes we build most often. Plenty of homes do not fit them. Wider footprints, a third bathroom upstairs, a full ground floor reconfiguration underneath, or a heritage roofline that has to be worked around rather than replaced.

We build those too, priced against your plans rather than squeezed into a package. Same fixed price contract, same standards, same specification. Custom builds generally run $270,000 to $400,000 depending on size and what we find underneath.

Custom builds

Priced to your plans

  • Any size or configuration
  • Ground floor works included in scope
  • Heritage and character homes
  • Structural upgrades where needed

Every plan is drawn to suit your home. Package price covers the new upper floor works. Design, engineering and council approvals, plus site set-up, are quoted separately as preliminaries, at roughly $30,000.

What’s included, what’s quoted separately and how it compares with moving: read our second storey cost guide.

The Strava difference

A solid, quieter upstairs.

Most second storey additions leave the cavity between the new floor joists empty. While the floor does the job, that hollow space lets sound travel. As a result, footsteps carry straight down to the rooms below.

For early Strava Group projects we include acoustic insulation in the subfloor free. Insulation batts fill the space between the new floor joists, with yellow tongue particleboard flooring laid over the top. It is a simple step that makes for a quieter upstairs.

Free

Acoustic insulation included between the new floor joists on early packages, while the offer runs.

✦

Yellow tongue particleboard flooring laid over the joists, ready for your timber, tile or carpet finish.

↓

Helps reduce noise transfer between levels for a quieter upstairs, especially with the right ceiling system.

+

Hebel or Nexcore upgrade available where the existing structure can take the additional weight.

Your upper floor, layer by layerSection
  1. Floor finishTimber, tile or carpet
  2. Yellow tongue particleboardFlooring sheets over the joists
  3. Engineered floor joistsThe new upper floor structure
  4. Acoustic insulationBetween the joists, included free
  5. Plasterboard ceiling belowTo the rooms downstairs
  6. Existing top plateOn the walls of your house

Upgrade: Hebel or Nexcore flooring (subject to structural capacity)

Diagram is illustrative. Acoustic ratings apply to the complete floor and ceiling system, not the batts alone, and depend on the ceiling, insulation and joist design. Subfloor acoustic insulation is included where suitable, subject to engineering, access and final scope.

Before anything is designed

Can your house actually take a second storey?

This is the first question, and it usually gets skipped in favour of talking about floor plans. It is worth answering properly, because for roughly one house in six the answer is no, or not without spending money you would rather put into the addition itself.

01

What is under the house

Your house was built to hold up one storey. A second floor roughly doubles what the foundations carry. On plenty of Sydney blocks, particularly out west and up north where the soil moves with the weather, the foundations need strengthening first. That is a real cost, and you want to know about it before you fall in love with a floor plan.

02

What the walls are made of

A double brick house, a brick veneer house and a timber framed house each handle a new floor differently. The question is whether the weight can travel down through the walls you already have, or whether new supports need to appear somewhere you would rather they did not.

03

What the timber has been through

Framing that looked fine when you bought the place can be quietly damaged in ways that only matter once you ask it to hold a floor up. We look before we quote, not after.

04

What your council allows

Councils set a height limit, and most also protect your neighbours’ winter sunlight. Between them, those two rules often decide your ceiling heights and your roof shape before anyone draws anything.

05

Whether we can get a crane in

Narrow driveways, overhead power lines and steep blocks all add cost. Better to know at the start than in week three.

06

How we find out

An engineer checks the first three. We organise that before we give you a fixed price, because a price without it is a guess.

If your house cannot take a second storey without spending more than it is worth, we will tell you. Building out the back is usually the better answer in that case, and we build home extensions too.

Clear scope

What is included, and what is not.

Being upfront about both is exactly how we keep your fixed price genuinely fixed.

Included as standard

In the new upper floor package area.

Acoustic insulation in the subfloor, under yellow tongue particleboard flooring
Structural timber framing to engineer’s details
Wall framing and roof framing
Roofing
External cladding
Aluminium windows
Insulation
Plasterboard and setting
Internal doors, hardware and hinges
Skirting and architraves
Standard staircase allowance
Electrical allowance, LED downlights and smoke alarms
Bathroom allowance (where part of the package)
Painting to new upper floor areas
Builder supervision and construction management

Quoted separately if needed

Every existing home is different, so these are assessed per property.

Structural steel beams (unless listed)
Footing, pier or foundation upgrades
Additional bracing to the existing house
Ground floor renovations or layout changes
New downstairs kitchens, bathrooms or laundries
Existing termite, rot, water or defect repairs
Electrical mains, switchboard or stormwater upgrades
Air conditioning upgrades
Design, engineering, BASIX and council approvals, plus site set-up (preliminaries)
Rock excavation or unforeseen ground conditions
Premium window, cladding or staircase upgrades
Any works outside the new upper floor package area

Want the full detail?

The complete inclusions and exclusions, right down to hardware, fixtures, fittings, finishes and specifications, are provided in detail when you enquire, and confirmed in your contract.

How the fixed price works

Our fixed price packages apply to the standard new upper floor works listed above. If your property needs structural steel, footing upgrades, extra bracing, service upgrades, defect repairs or downstairs renovation works, those items are assessed and quoted separately, clearly, before you commit. Where something genuinely cannot be priced until the roof comes off, it is listed as a provisional sum with a stated allowance rather than hidden inside the total.

The first decision

Up or out?

Most people arrive having already decided. The block usually answers it before taste does.

Go up

$3,500 to $5,500 per m²

Choose a second storey if the yard is the reason you bought the place, the block is narrow, or you have already used most of your available site coverage.

Going up buys bedrooms without buying land, and it leaves the garden intact. It costs more per square metre and usually needs a longer approval pathway, but on a tight block it is often the only way to add real space.

Extend out

$2,500 to $4,500 per m²

Choose a ground floor extension if you have real yard to give up and still have some left, the block is wide rather than deep, or the existing structure cannot carry a floor economically.

Ground floor work is cheaper per square metre, you can often stay living there, and it avoids the structural question entirely. A rear home extension is frequently the better value answer.

If the existing house needs work regardless, a full renovation staged alongside the addition costs less than doing them five years apart, because you pay the preliminaries once and open the walls once. Second storey additions are sometimes called home additions or first floor additions. They are the same thing, and we build them under any name.

Built Once. Built Right.

See exactly how we build, and why

Four-coat waterproofing, tensioned X bracing, hand-cut roofs and inspections you can check yourself. Every method explained, including what’s standard and what’s an upgrade.

Plan · Manage · Build

Your second storey, step by step.

Our proven building process is designed to customise your project, avoid cost traps and deliver your vision with minimum disruption.

  1. First, we review your enquiry, site, timeframe and budget. Then we contact you within 24 to 48 business hours to arrange a consultation.

Why Strava Group

A licensed builder who knows what is behind the wall.

A stronger standard inclusion

Acoustic insulation in the subfloor comes free on early packages, giving a quieter upstairs than a floor left with an empty cavity.

Structure first, always

Over a decade across site and project management on residential and commercial builds, backed by a trade background. Your addition is framed and supported to our internal Above Standard Carpentry Specification, so the new level feels solid, aligned and original.

Clear scope and fixed pricing

Transparent inclusions and exclusions from day one, so you know exactly what your project covers before you commit. NSW Builder’s Licence 487370C.

Also exploring other options? Strava Group builds home renovations, home extensions and custom homes across Sydney. See our recent work in the gallery.

Get in touch

Talk to a builder about your home.

Tell us about your home and what you would like upstairs. We will let you know whether your property suits a second storey and which package fits. No cost, no obligation.

Good to know

Frequently asked questions.

Google Reviews
5.0·Google reviews
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.
AT

Aloona T.

Google review

Read our Google reviews

Service areas

Second storey additions across Sydney.

Select your suburb for local council height controls, the housing stock we see there and what additions in that area typically cost.

See all Sydney service areas.

Get your free quote today.

Ready to build up?

Contact Strava Group for a free consultation and a quote for your second storey addition, with acoustic insulation in the subfloor included while the offer runs and a fixed price scope you can rely on. Building up is one of the most cost effective ways to add space and value under current NSW housing and construction settings.