Second Storey Addition in Illawarra
Your house is bursting at the seams. Your land is not.
Why Build Up?
You need more space but you have run out of ground. You face a choice: sell the family home, sacrifice the backyard to a ground-floor sprawl, or build up.
A second storey solves all of these without touching your backyard. You stay in your location. You double your living space on the same footprint.
Get Expert Help From Adlington Homes
Sound Familiar?
- ✓Kids sharing bedrooms they have outgrown?
- ✓No parents' retreat away from the noise?
- ✓Worried that extending out leaves no grass for the dog?
- ✓Missing ocean or escarpment views that a second level would capture?
Ways To Connect
Ways To Connect With Adlington Homes
Investment
What It Costs (2026 Illawarra Rates)
Indicative Illawarra budgeting ranges, reviewed October 2026:
- ✓Standard second storey (3 bed, 1 bath, open landing): $3,500–$4,500/m²
- ✓Premium second storey (master suite, retreat, balcony, ensuite): $4,500–$5,500/m²
- ✓Complex (raked ceilings, cantilevers, structural steel): $5,000–$6,500+/m²
A typical 80m² upper level (3 bedrooms, bathroom, landing) costs $280,000–$360,000. A premium 120m² upper level (4 bedrooms, 2 bathrooms, parents' retreat, balcony) costs $540,000–$660,000. These include structural reinforcement of your existing frame, new staircase, all internal fit-out, and external cladding/roofing to match. Pricing reviewed October 2026; site access, structural work, finishes and the approval pathway can change the final figure.
Decision Point
Second Storey Addition or Knock-Down Rebuild?
Building up works best when the home below is worth keeping. If the existing structure, layout and services all need major work, rebuilding may be the more practical long-term option.
A second storey addition may suit you if:
- ✓You want to stay in the same home and neighbourhood
- ✓The existing structure can be reinforced at a sensible cost
- ✓You need bedrooms or a retreat without losing the backyard
- ✓The current ground-floor layout already works well
A knock-down rebuild may suit you if:
- ✓The existing structure needs extensive repair before it can carry another level
- ✓You also want to completely redesign the ground floor
- ✓Reinforcement and renovation costs are approaching the cost of rebuilding
- ✓The site and approval pathway make a new home more practical
We test the structure, site constraints, likely approval path and budget during feasibility before recommending either direction.
Local Expertise
The Technical Reality
Building up is more complex than building out. Your existing house was designed to hold a roof, not a second house. Here is what we manage:
Structural assessment
Our engineer inspects your existing frame (timber or steel), your footings, and your slab. Most timber-frame homes in the Illawarra (1960s–90s brick veneer) can support a second storey with reinforcement: laminating existing studs, adding steel posts to transfer loads, or underpinning footings where needed.
Roof removal and weather protection
We remove your existing roof to build above. This exposes your ground floor to weather for a period. We use industrial-grade tarps and temporary roofing to protect your ceilings and walls, schedule this phase for dry weather windows, and fast-track the new roof to lock-up.
Staircase placement
You lose some ground-floor space for the stairs. A straight staircase takes about 4m × 1m. We aim to place it in existing hallways, a spare study, or under-utilised space so your main living flow stays intact.
Matching the exterior
The upper level must look like it was always there. We match your roof pitch, eave overhang, window proportions, and cladding material. If your existing home is face brick, we either continue the brick (if it is still available) or clad the upper level in a complementary material like Scyon Linea or rendered lightweight construction.
Our Work
Recent Second Story Additions Projects
- 01
Feasibility + engineering — we confirm your foundations and frame can take the load. 2–4 weeks.
- 02
Design + 3D visualisation — we design the upper level to suit your brief and show you exactly what it looks like from the street. 4–8 weeks.
- 03
Planning approval (DA or CDC) — we confirm whether the proposal and property meet the NSW complying-development standards or require a development application. Timing depends on the pathway and site constraints.
- 04
Demolition + protection — roof off, structure tarped. 1–2 weeks.
- 05
Framing + roof — steel and timber frame craned in, new roof installed. 3–4 weeks to lock-up.
- 06
Fit-out — insulation, plasterboard, electrical, plumbing, flooring, painting. 8–12 weeks.
- 07
Stair breakthrough + finishing — we cut the floor, install the staircase, and connect the two levels. 2–3 weeks.
- 08
Handover — final inspections, occupation certificate, keys.
Features
Is a Second Storey Addition Worth It in Illawarra?
It can be when the existing home is structurally suitable, the ground-floor layout is worth keeping and preserving outdoor space matters more than minimising cost per square metre.
- ✓Capture the view — many Illawarra homes sit below their view potential. Our Mangerton Second Storey Addition shows what a second level can unlock; homeowners are often surprised by the ocean and escarpment views hidden above their existing roofline.
- ✓Zone your living — a two-storey home naturally separates noisy living areas (downstairs) from quiet sleeping areas (upstairs), so parents and teenagers get their own territories.
- ✓Keep the yard — land is expensive in the Illawarra (a 600m² block in Thirroul is worth $1.5M+), and building up means you keep every square metre of outdoor space.
- ✓Add serious value — a second storey addition typically adds 1.5–2× the construction cost to your property value, because you are effectively doubling the home's floor area.
Good to Know
DA or CDC for a Second Storey Addition in Illawarra?
NSW allows some home alterations and additions to use the complying development pathway, but only when the proposal and the land meet every relevant standard. Otherwise, a development application is required.
- ✓CDC is a combined planning and construction approval for qualifying straightforward development and can be assessed by council or an accredited certifier.
- ✓Height, setbacks, landscaped area, privacy and site constraints such as heritage, bushfire and flooding can determine whether CDC is available.
- ✓A DA is the usual pathway when the proposal does not meet the complying-development standards or needs a merit assessment.
- ✓Either pathway still needs accurate drawings, structural engineering and certification before construction begins.
The approval path must be confirmed for your property. We check it during feasibility before design work advances too far.
Secure Your Complimentary Design & Build Consultation
During this consultation, you will receive:
- Personalised Design Consultation
- On-Site Walk-Thru and Inspection
- Contractor Collaboration
- Detailed Selections Checklist & Comparison
- Preliminary Estimate and Budget Outline
- Project Timeline For Completion
- Access to our Trusted Partner Network
Guarantee
The Adlington Assurance
We guarantee that every aspect of your project will be completed to the highest standard of quality and craftsmanship.
If you're not completely satisfied with any aspect of the project, we'll work with you to make it right until you're completely happy.
FAQs
Frequently Asked Questions
Can we live in the house during construction?+
We recommend moving out for the roof removal and framing phase (approximately 4–6 weeks). Once the new roof is on and the house is weather-tight again, you can move back in while we complete the internal fit-out upstairs. We will discuss the specific plan for your project.
How long does the whole process take?+
Design and approvals: 4–6 months. Construction: 6–9 months. Total from first meeting to move-in: 12–15 months. Start the conversation early.
Will my house look top-heavy?+
Not if the design is right. We match proportions, roof pitch, and materials. A well-designed second storey looks like it was always part of the house. We show you street-view renders before committing.
Is my house strong enough?+
Most Illawarra homes can support a second storey with reinforcement. We confirm this with an engineering assessment during feasibility, before you spend money on design.
What about my heating/cooling?+
Removing the roof means removing existing ducted systems. We design a new HVAC solution for both levels as part of the project. Many clients upgrade to a split zoned system at this point.
Is Your House Strong Enough?
Do not guess about structural walls. Book a site meeting with Duane Adlington. We will assess your existing home and advise you on whether "going up" is the right move.
From Coast to Countryside, We've Built It All
Whether your dream destination encompasses ocean breezes or pastoral charm, discover how our team can make your property vision a reality. For five decades, Adlington Homes have lent their expertise to diverse projects across the Illawarra and beyond.
- ✓Wombarra
- ✓Austinmer
- ✓Coalcliff
- ✓Scarborough
- ✓Thirroul
- ✓Bulli
- ✓Russell Vale
- ✓Woonona
- ✓Bellambi
- ✓Corrimal
- ✓Tarrawanna
- ✓Towradgi
- ✓Fairy Meadow
- ✓Albion Park Rail
- ✓Port Kembla
- ✓Shell Cove
- ✓Unanderra
- ✓Balgownie
- ✓Fernhill
- ✓Mount Ousley
- ✓Mount Pleasant
- ✓Gwynneville
- ✓Keiraville
- ✓North Wollongong
- ✓Wollongong
- ✓Mangerton
- ✓West Wollongong
- ✓Coniston
- ✓Figtree
- ✓Barrack Heights
- ✓Flinders
- ✓Kanahooka
- ✓Oak Flats
- ✓Warilla