What types of custom extensions do you build in Thornleigh?

We specialize in bespoke home extensions in Thornleigh including kitchen extensions with modern island benches, bathroom additions with luxury finishes like Venetian micro-cement, structural modifications for enhanced floor plans, and complete home transformations. Our extensions are designed to complement Thornleigh's established residential character and natural surroundings while seamlessly integrating with your home's existing architecture and enhancing both space and property value. We also have expertise in sloping site extensions, common in Thornleigh's varied terrain.

How long does a custom extension project take in Thornleigh?

Project timelines vary based on scope and complexity. A typical custom extension in Thornleigh, including kitchen and bathroom renovations with structural modifications, can take 3-6 months from construction start to completion. We begin with our PAC-certified pre-construction process to align your design, budget, and timeline before breaking ground, ensuring a smooth and predictable build experience that respects your lifestyle, neighbourhood character, and any site-specific considerations such as slope or access.

Can you renovate older homes in Thornleigh?

Absolutely. We have extensive experience transforming older properties in Thornleigh, including 1950s weatherboard houses, into modern homes while respecting their heritage character and the suburb's established aesthetic. Our approach includes sensitive structural modifications to improve floor plans, updating internal and external surfaces, installing premium finishes, and enhancing functionality through thoughtful design that honors the home's original charm while complementing Thornleigh's leafy, residential character and natural surroundings.

What makes AGATHĒ different from other builders in Thornleigh?

AGATHĒ embodies three core values: Quality, Generosity, and Honor. We're committed to exceptional craftsmanship with premium finishes, transparent and collaborative processes, and our unique charitable initiative of building a house for every house built. We specialize in healthy, high-performance homes that prioritize wellness, sustainability, air quality, and natural light. Our PAC-certified pre-construction process and education-led approach ensure you're informed and confident throughout your build, with particular sensitivity to Thornleigh's established character, varied terrain, and site-specific challenges.

Do you offer design services for custom extensions in Thornleigh?

Yes, we offer comprehensive pre-construction services including design collaboration, budget alignment, and timeline planning. Whether you're working with your own architect or need design guidance, our PAC-certified pre-construction process ensures your vision, budget, and timeline are perfectly aligned before construction begins. We also specialize in architectural construction, bringing complex designs to life with precision and care while respecting Thornleigh's planning considerations, terrain challenges, and neighbourhood character.

What areas do you service for custom extensions?

While we're based on Sydney's Northern Beaches, we service Thornleigh and the broader Upper North Shore and Hills District regions. We specialize in luxury renovations and custom extensions throughout Sydney's premium suburbs, bringing our expertise in premium craftsmanship, healthy homes construction, and bespoke design to discerning homeowners who value quality, heritage sensitivity, and exceptional results.

Do you work with council requirements in Thornleigh?

Yes, we have extensive experience navigating Hornsby Shire Council requirements for Thornleigh properties. Our pre-construction process includes thorough assessment of planning regulations, heritage considerations, sloping site requirements, and local building codes. We manage all council approvals, certifications, and compliance requirements, ensuring your extension project meets all necessary standards while achieving your design vision and respecting the suburb's established character and environmental controls.

Can you build extensions on sloping blocks in Thornleigh?

Yes, we have extensive experience with sloping sites and varied terrain common throughout Thornleigh. We understand the specific engineering and design considerations required for slope construction, including retaining walls, drainage solutions, and foundation systems. Our approach maximizes the potential of sloping blocks, creating extensions that work with the natural contours while enhancing views, natural light, and outdoor connections. We handle all structural engineering, council approvals, and construction challenges to deliver exceptional results on challenging sites.

CUSTOM EXTENSIONS

THORNLEIGH

This home renovation transformed a 1950s property with modern kitchen design, micro-cement bathrooms, and updated layout. Premium finishes and new driveway enhanced functionality while honouring the suburb's established residential character and natural surroundings.

CUSTOM EXTENSIONS IN THORNLEIGH

This transformative project breathed new life into a rundown 1950s weatherboard house, seamlessly blending its historic charm with contemporary flair. Extensive structural modifications facilitated significant alterations to the floor plan, enhancing spatial flow and functionality. The renovation showcased two meticulously crafted bathrooms adorned with Venetian micro-cement rendered surfaces, embodying modern sophistication.

A redesigned kitchen, complete with an inviting island bench, became the heart of the home. The addition of a new driveway enhanced accessibility and curb appeal, while comprehensive updates to both internal and external surfaces revitalized the property’s aesthetic appeal. This project exemplifies the seamless integration of bespoke design and meticulous craftsmanship, resulting in a home that harmoniously balances heritage charm with contemporary living.

Elegant home entrance with blue door, white siding and staircase surrounded by landscaped gardens at a Thornleigh property with custom extension

Bright modern kitchen with island, black pendant lights and garden views—premium Thornleigh custom extension by AGATHĒ builders

Contemporary bathroom with walk-in shower, dark tile accents and wooden-framed mirror at a Thornleigh custom extension renovation

Modern kitchen faucet with blue subway tile backsplash detail from a Thornleigh home undergoing custom extension renovation

Recessed ceiling lighting with white cabinetry in a Thornleigh custom extension interior renovation

Front porch featuring window, beige siding and planter box with native plants—part of custom extension work in Thornleigh

Pink and red flowering garden beds framing weatherboard exterior, showcasing custom extension craftsmanship in Thornleigh

Built-in mudroom storage with timber bench, wall hooks and hardwood flooring in a Thornleigh home featuring custom extension work

Modern bathroom featuring blue subway tiles, timber vanity and glass-enclosed shower in a luxury Thornleigh custom extension

AGATHĒ builders reviewing completed custom extension project in Thornleigh, showcasing quality craftsmanship and client collaboration

Garden view through window with flowering landscape at a Thornleigh property featuring quality custom extension work

WONDERING WHERE TO START?

Transform your Thornleigh home with Sydney's trusted renovation experts. Whether you're dreaming of a stunning extension, luxury kitchen upgrade, or complete home transformation, we make visions reality. Ready to start your journey? Book a consultation and let's create something extraordinary together.

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DISCOVER OUR SERVICES

Open sliding glass door to dining area with wooden table and chairs, potted plants outside, white siding, and small porch with wooden steps.

HOME RENOVATIONS

From partial to full-scale renovations, our services are designed to transform your existing spaces into stunning, family living environments.

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Front view of a house with a blue front door and a small porch, surrounded by colorful flowering bushes and a well-maintained lawn.

CUSTOM EXTENSIONS

Expand your Northern Beaches Home with our bespoke extension solutions that seamlessly integrate with your home’s current design, enhancing both space and value.

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PRE CONSTRUCTION

Start your build the right way with our PAC-certified pre-construction process – a collaborative approach that aligns your design, budget, and timeline.

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ALTERATIONS & ADDITIONS

Refresh your existing space with thoughtful alterations and additions that enhance flow, functionality, and the way your home supports your lifestyle.

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HEALTHY HOMES

Prioritise wellness and sustainability with our Healthy Homes approach – designed to improve air quality, light, and overall comfort in every corner.

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Interior of a modern, well-lit living area at night with a view of the dark, cloudy sky through large windows.

ARCHITECTURAL CONSTRUCTION

Bring your architect’s vision to life with precision. Our expert team delivers complex builds with clarity, care, and exceptional craftsmanship.

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PROJECT MANAGEMENT

From design to delivery, we manage every detail of your build to ensure a smooth, on-time, and on-budget build that reflects your vision.

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Modern house with concrete and black metal exterior, large glass windows, and minimalist landscaping, surrounded by trees and rocky ground.

GRANNY FLATS

Create flexible, modern living spaces with our custom-designed granny flats – ideal for multigenerational living, guests, or extra income.

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A man kneeling on the ground installing a verticale support beam between a brick and stone wall, with a power drill in his hand and construction tools around him.

CHALLENGING SITES

No site too steep or complex – we specialise in building on challenging terrain with smart solutions that maximise space, access, and design potential.

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CUSTOM EXTENSIONS

THORNLEIGH

CUSTOM EXTENSIONS IN THORNLEIGH

WONDERING WHERE TO START?

DISCOVER OUR SERVICES

HOME RENOVATIONS

CUSTOM EXTENSIONS

PRE CONSTRUCTION

ALTERATIONS & ADDITIONS

HEALTHY HOMES

ARCHITECTURAL CONSTRUCTION

PROJECT MANAGEMENT

GRANNY FLATS

CHALLENGING SITES

READY TO BUILD?

FROM SYDNEYS NORTH TO NEWCASTLE

Healthy Homes. Honest Work. Built to Last.