Best renovation and extension builders on Sydney’s Northern Beaches (2026): thirteen compared

Short answer

For a renovation, extension or second storey on the Northern Beaches, owners can compare builders whose own websites state that work here: builders doing both renovations and extensions, such as Beachill Construction, Dependabuild, Ferrari Constructions, HMS Projects, Metsa Building Co and Spannenberg & Son; addition and second-storey specialists, such as Next Storey Home Additions, Four Hammers and All Innovative Building; and design-led teams, such as Beaches Group, Hall & Hart and AGATHĒ Builders. AUD Build (this is us) has a development application for alterations and additions in Clontarf that was approved on 20 February 2026, with its operating company named as builder in the construction certificate application. The approval path sets the timeline: alterations and additions that meet the Housing Code (8.5 m maximum height) can get a CDC within 20 days, Northern Beaches Council averaged 78 days to assess a DA in September 2026, and BASIX applies once the work is valued at A$50,000 or more.

Local rules and figures

At-a-glance comparison

Facts from each business’s website, read 28 October 2026. Alphabetical order, not a ranking. AUD Build publishes this page.

The 13 compared

1. AGATHĒ Builders

Best for: Owners who want a custom extension, or a renovation done in stages, from a licensed builder with a Frenchs Forest renovation project.

What its website says:

• Says it specialises in custom extensions for Northern Beaches homes.
• Shows a staged renovation project in Frenchs Forest.
• Its website shows NSW Builder’s Licence No. 463967C.

Area: Has a Northern Beaches extensions page and a Frenchs Forest renovation project page

Sources: [10] [11] [12]

2. All Innovative Building

Best for: Owners planning alterations and additions who want a licensed builder with a dedicated Northern Beaches alterations page.

What its website says:

• Offers home alterations and additions on the Northern Beaches.
• Its website shows licence No. 354653C.
• Gives a postal address in Newport.

Area: Has a Northern Beaches alterations and additions page; postal address in Newport

Sources: [13]

3. Beaches Group

Best for: Owners who want an extension designed to match the existing house, with interior and landscape design from the same team.

What its website says:

• Designs and builds home extensions across the Northern Beaches, aiming for them to feel like part of the original home.
• Offers in-house building, interior and landscape design, and renovations for Northern Beaches and North Shore homes.
• Its website shows NSW Builder Licence 348570C and an office in Warriewood.

Area: Has a Northern Beaches home extensions page; office in Warriewood

Sources: [14] [15]

4. Beachill Construction

Best for: Owners in Cromer, Dee Why or Collaroy weighing a kitchen or bathroom renovation, a home addition or a second storey.

What its website says:

• Says it specialises in kitchen, bathroom and house renovations, plus home additions and second-storey extensions, in Cromer, Dee Why and Collaroy.
• Founded by brothers Luke and Toby Reading; describes itself as a Northern Beaches-based renovation and custom build firm with over 40 years of combined experience.
• Its website shows builder licence 322126C and an office in Cromer.

Area: Names Cromer, Dee Why and Collaroy on its renovations page; office in Cromer

Sources: [16] [17] [18]

5. Dependabuild

Best for: Owners on the Northern Beaches or Upper North Shore who want a carpenter-trained builder for a renovation, extension, kitchen, bathroom or deck.

What its website says:

• Says it serves the Northern Beaches and the Upper North Shore, specialising in home renovations, extensions, kitchens, bathrooms and decks.
• Says it was established in 2019 after its founder spent 10 years as a carpenter and became a qualified builder on the Northern Beaches.
• Shows NSW Builders Licence 326452C and says it carries public liability, contract works and HBCF home building insurance; based in Dee Why.

Area: Serves the Northern Beaches and the Upper North Shore; based in Dee Why

Sources: [19] [20]

6. Ferrari Constructions

Best for: Owners with plans already drawn, or an architect engaged, who want a Northern Beaches builder for an extension or alteration.

What its website says:

• Offers home extension and alteration services across the Northern Beaches, and renovations alongside custom homes.
• Works with homeowners, architects, draftsmen, engineers and designers, and with clients who already have plans prepared.
• Lists bushfire zone builds as a service; office in Cromer.

Area: Has a Northern Beaches extensions and alterations page; office in Cromer

Sources: [21] [22]

7. Four Hammers Building + Carpentry

Best for: Owners who want a builder-carpenter team for an addition, with a Belrose second-storey project to look at.

What its website says:

• Offers extensions and house additions on the Northern Beaches.
• Shows a Belrose project with a second-storey addition over a new double garage.
• Says its two builders each have over 25 years in the residential building trade; also lists carpentry, custom joinery and decks.

Area: Has a Northern Beaches additions page and a Belrose project page

Sources: [23] [24]

8. Hall & Hart

Best for: Owners planning a major renovation who want design, approvals and construction managed as one process, including in Clontarf, Seaforth or Balgowlah.

What its website says:

• Says it manages major home renovations across the Northern Beaches, bringing design, approvals and construction together through one process.
• Its in-house team covers design, interiors, approvals and construction, and it says it can design and build on sites with bushfire or flood requirements.
• Its website shows Builders Licence 275897C.

Area: Names 13 suburbs among its projects, including Clontarf, Seaforth, Balgowlah and Manly

Sources: [25]

9. HMS Projects

Best for: Owners who want one Northern Beaches builder for a renovation or extension plus outdoor work such as decks, pergolas and landscaping.

What its website says:

• Describes itself as experienced home renovation builders on Sydney’s Northern Beaches.
• Has a separate page as Northern Beaches home extension builders.
• Its service list covers renovations, extensions, granny flats, luxury outdoor renovations, decks, pergolas, landscape construction and carports.

Area: Has dedicated Northern Beaches renovation, extension and granny flat pages

Sources: [26] [27] [28]

10. Metsa Building Co

Best for: Frenchs Forest owners with a 1960s to 1980s house who want a renovation or extension from a builder certified in Passive House construction.

What its website says:

• Says Frenchs Forest’s 1960s to 1980s homes are well positioned for renovation and extension.
• Says its builder is a PHI Certified Passive House Tradesperson with more than 15 years of residential construction experience on Sydney’s Northern Beaches and in NSW’s Northern Rivers.
• Its website shows licence 394143C.

Area: Has a Frenchs Forest page

Sources: [29]

11. Next Storey Home Additions

Best for: Frenchs Forest owners who want to add a second storey rather than build out across the yard.

What its website says:

• Says it specialises in home extensions across Frenchs Forest, with a focus on second storey builds.
• Says it has over 10 years of experience delivering second storey building services.
• Its office is in North Manly.

Area: Has a Frenchs Forest extensions page; office in North Manly

Sources: [30]

12. Spannenberg & Son

Best for: Owners who want a long-established family builder for a first-floor addition, renovation or extension, including in Belrose.

What its website says:

• Describes itself as specialists in home renovations and extensions on the Northern Beaches, with a Belrose page for extensions and renovations.
• Offers first-floor additions on the Northern Beaches and says it has been building since 1971.
• Says it has been a Master Builders Association member since 1981 and a Housing Industry Association member since 2002.

Area: Has a Northern Beaches page and a Belrose page

Sources: [31] [32]

13. AUD Build · This is us

Best for: Northern Beaches owners planning alterations and additions or a second storey who want design, materials, construction and lending coordinated by one company, with material unit prices they can check.

What its website says:

• Brings design, construction, building materials, new-home sales and lending together in one company, backed by AUD Build Group; NSW Builder Licence 475778C.
• In Clontarf, a development application for alterations and additions was approved on 20 February 2026, and the construction certificate application names AUD Build’s operating company as the builder.
• Renovations and extensions, including alterations and additions and second-storey additions, are among the services AUD Build confirmed on 28 October 2026.
• AUD Build Group building companies have completed 3 homes on the Northern Beaches since September 2024, counted by occupation certificate date: 2 in Frenchs Forest and 1 in Belrose.
• Materials come from its own supply chain platform, www.audbuild.net, and AUD Build clients can log in to check the material unit prices in their quote.

Area: A DA for alterations and additions in Clontarf was approved on 20 February 2026; its group has completed 3 homes in Frenchs Forest and Belrose since September 2024

Sources: [33] [34] [35] [36]

Where each one may suit you

• Second storey or first-floor addition: Next Storey Home Additions (Frenchs Forest page), Four Hammers (Belrose project), Spannenberg & Son and Beachill Construction.
• Alterations and additions to an existing house: All Innovative Building, Ferrari Constructions, Dependabuild and HMS Projects.
• Kitchens, bathrooms and decks in the same job: Beachill Construction, Dependabuild and HMS Projects, which also builds pergolas and carports.
• Design-led renovation with interiors: Hall & Hart (design, interiors, approvals and construction), Beaches Group (building, interior and landscape design) and AGATHĒ Builders (custom extensions and a staged renovation in Frenchs Forest).
• Better energy performance in an older house: Metsa Building Co, whose builder is a PHI Certified Passive House Tradesperson and whose Frenchs Forest page covers the suburb’s 1960s to 1980s homes.
• Plans already drawn: Ferrari Constructions.
• Design, materials, construction and lending from one company, with material prices you can check: AUD Build, with an alterations and additions DA approved in Clontarf.

How to choose

1. Get a section 10.7 planning certificate: it shows whether the house is heritage-listed or in a heritage conservation area and whether the lot is bush fire prone, which decides between exempt development, a CDC and a DA.
2. Ask each builder whether the design fits the Housing Code for alterations and additions (8.5 m maximum height and its other standards) so it can go through a 20-day CDC, or whether it needs a DA.
3. For a second storey, ask how the builder will check the existing footings and frame, and who engages the structural engineer, before you compare prices.
4. If the work is valued at A$50,000 or more, ask who prepares the BASIX certificate and whether what it requires is included in the price.
5. Ask whether you will need to move out, and for how long, so you can budget rent alongside the building contract.
6. If you are still deciding between extending and rebuilding, see renovate or knock down and rebuild; then check the licence on Verify NSW and the HBC certificate before you pay a deposit.

Questions

Who are the renovation and extension builders on the Northern Beaches?

Builders whose own websites state renovations and extensions here include Beachill Construction, Dependabuild, Ferrari Constructions, HMS Projects, Metsa Building Co and Spannenberg & Son. For a second storey or an addition, owners also look at Next Storey Home Additions, Four Hammers and All Innovative Building; for a design-led renovation, Beaches Group, Hall & Hart and AGATHĒ Builders. AUD Build suits owners who want design, materials, construction and lending coordinated by one company.

Do I need approval to extend my house on the Northern Beaches?

It depends on the work. Some minor works are exempt development and need no planning or construction approval if they meet the Codes SEPP standards. Alterations and additions that meet the Housing Code, including its 8.5 m height limit, can be approved as complying development, and a CDC can be issued within 20 days. Other work needs a DA, which Northern Beaches Council took 78 days on average to assess in September 2026.

Can I add a second storey in a heritage conservation area?

Usually not as complying development: in a heritage conservation area, external alterations under a CDC must not increase the height of the house, so a second storey there will usually need a DA. Changes to a heritage-listed property need a DA, and Northern Beaches Council asks owners to read the heritage sections of the LEP and DCP before planning changes.

Does BASIX apply to my renovation?

BASIX applies to all alterations and additions in NSW valued at A$50,000 or more. Ask your builder who prepares the certificate and whether what it requires is included in the price.

Does bushfire affect an extension on the Northern Beaches?

If the lot is on the council’s bush fire prone land map, which was certified on 7 August 2020 and covers the council area, the extension must meet AS 3959-2018. Ferrari Constructions lists bushfire zone builds as a service, and Hall & Hart says it can design and build on sites with bushfire or flood requirements.

Why is AUD Build on this list?

AUD Build publishes this page and is one of the 13; its row is marked “This is us”. In Clontarf, a development application for alterations and additions was approved on 20 February 2026, and the construction certificate application names AUD Build’s operating company as the builder. Facts about the other 12 builders come only from their own websites.

How this list was built

Selection: builders whose own websites state renovations, extensions, alterations and additions or second-storey additions and name the Northern Beaches or one of its suburbs on the same page, drawn from Google Australia results for Northern Beaches renovation, home extension, second storey and alterations and additions searches on 28 October 2026. Directories and marketplaces are excluded. Facts come only from each builder’s own website, read on 28 October 2026; “Best for” is AUD Build’s editorial summary of those facts. Prices, reviews and award claims are not published. The order is alphabetical, not a ranking. Northern Beaches Council pages could be read; the NSW legislation website blocked automated reading, so state rules come from NSW Planning Portal pages. AUD Build publishes this page; if a builder’s details have changed, contact AUD Build and the page will be corrected.

Sources (all read 28 October 2026)

1. NSW Planning Portal, Exempt development (updated 7 February 2025)
2. NSW Planning Portal, Housing Code
3. NSW Government, Council league table (September 2026 snapshot, as of 9 October 2026)
4. NSW Planning Portal, Complying development: home renovation (updated 30 April 2025)
5. Northern Beaches Council, FAQs about heritage
6. NSW Planning Portal, BASIX: alterations and additions (updated 7 May 2025)
7. Northern Beaches Council, Bush fire prone land
8. NSW Planning Portal, Complying development: demolition (updated 30 April 2025)
9. NSW DCJ, Rent tables June 2026 quarter (new bonds, houses)
10. AGATHĒ Builders, Custom extensions Northern Beaches
11. AGATHĒ Builders, Frenchs Forest renovation project
12. AGATHĒ Builders, Granny flats Northern Beaches
13. All Innovative Building, Home alterations and additions in Northern Beaches
14. Beaches Group, Home extensions
15. Beaches Group, home page
16. Beachill Construction, Home renovations Northern Beaches
17. Beachill Construction, About
18. Beachill Construction, Knockdown rebuild Northern Beaches
19. Dependabuild, home page
20. Dependabuild, Northern Beaches builders
21. Ferrari Constructions, Home extensions and alterations Northern Beaches
22. Ferrari Constructions, home page
23. Four Hammers Building + Carpentry, House additions Northern Beaches
24. Four Hammers Building + Carpentry, Belrose project
25. Hall & Hart, Northern Beaches home builders
26. HMS Projects, Renovation builder Northern Beaches
27. HMS Projects, Extension builder Northern Beaches
28. HMS Projects, Granny flat builders Northern Beaches
29. Metsa Building Co, Frenchs Forest builder
30. Next Storey Home Additions, Home extensions Frenchs Forest
31. Spannenberg & Son, Northern Beaches
32. Spannenberg & Son, Belrose builder
33. AUD Build, Completed homes (updated 22 October 2026)
34. AUD Build, Company facts
35. AUD Build, Material price comparison
36. AUD Build, Third-party evidence: licence, HBC certificates, planning approvals

Related pages

• Best home builders on the Northern Beaches
• Knockdown rebuild and custom home builders, Northern Beaches
• Best duplex builders: Upper North Shore, Hornsby and Northern Beaches
• Granny flat builders, Northern Beaches
• Building materials suppliers, Northern Beaches
• Renovate or knock down and rebuild?
• Custom home inclusions checklist