Custom Granny Flat Builder
Create additional living space or a secondary dwelling with a licensed builder focused on practical solutions, clear communication and quality construction from start to finish.
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Licensed Builder 285023c
Insured & Warranty Backed
Custom Built Solutions
Residential Specialists
Why Homeowners Choose JG Building
Trusted Granny Flat Builder Across Central Coast, Newcastle & North Sydney
JG Building & Construction is trusted by homeowners across the Central Coast, Newcastle & North Sydney for high-quality granny flats and custom residential building solutions, from secondary dwellings and family accommodation to tailored builds designed around your property and lifestyle.
With a strong focus on communication, practical advice and quality, we’re not just building granny flats; we’re delivering a smoother, more reliable building experience from start to finish.
Create More Space Without Moving
Unlock the potential of your property with a custom-built granny flat. Whether you’re accommodating family, generating rental income, or creating a private retreat, we build high-quality granny flats designed around your goals.
Our Granny Flat Services
Custom granny flats, secondary dwellings and practical building solutions tailored to your property, goals and long-term needs.
Custom Granny Flats
Purpose-built granny flats designed to suit your block, lifestyle and long-term needs.
Secondary Dwellings
Create additional living space or generate investment opportunities with a professionally built secondary dwelling.
Difficult Site Builds
Experience delivering projects on sloping blocks, challenging access sites & properties requiring custom structural solutions.
Project Management
We help manage your project from the initial planning stages through to construction and completion.
TESTIMONIALS
What Our Clients Say
EXCELLENT
Based on 8 reviews
Posted on Google
Matt Champion11 January 2026Josh is extremely knowledgeable and skilled in transforming homes very efficiently and on time! Will definitely recommend to friends and family đź‘ŚPosted on Google
Michael Addicott2 November 2025We used JG building after an extensive search comparing various builders across a few criteria such as previous projects, communication, pricing and availability. JG building came in ahead on all criteria and we we’re happy to go with Josh for our extension and renovation. Our project included an en-suite extension, whole building render, painting, floor sanding, new kitchen and white picket fence. Through the whole build, Josh was a great communicator, not just with us but with all his trades, to make sure everyone had a clear understanding of the brief. As issues inevitably arose, as they do with renovations, Josh was quick to explore options to work through them, keeping our project running on time always. The quality of the outcome Josh delivered for us was fantastic. Attached are some pictures of the journey toward modernizing our home. When we bought the home it was overgrown, dated and tired. We made conscious decisions to design our finishes with a broad based appeal in mind, and as you can see from the photos, Josh has delivered this perfectly. Josh and JG Building and Construction are highly recommended for big and small jobs, and will continue to be our builder for any future projects.Posted on Google
Alex Burgin9 October 2025Josh was fantastic to deal with — great communication throughout the whole job and really high-quality workmanship. Everything was done when he said it would be, and the finish is spot on. Highly recommend.Posted on Google
Emanuel Francica29 September 2025As a structural engineer, I’ve had the opportunity to work alongside JG Building on a number of projects throughout the Central Coast and Newcastle. Their team consistently demonstrates a high level of professionalism, attention to detail, and commitment to quality construction. They follow engineering specifications accurately, communicate clearly, and are proactive in resolving site challenges. From an engineering perspective, it’s refreshing to collaborate with a builder who values compliance, safety, and workmanship to such a high standard. I have no hesitation recommending JG Building to anyone looking for a reliable and skilled builder.Posted on Google
Carl Spears31 August 2025Great service, great result! Friendly, approachable and communication was exemplary. Josh organised all the trades and everything done to schedule. Craftsmanship was impeccable. Bathroom renovation has never been easier. Highly recommend and we look forward to working with him again for our next job.Posted on Google
Shane Meister14 August 2025Josh and his crew were awesome—super easy to work with, dependable, and seriously talented. Love working with them and seeing the transformations. Highly recommend!Posted on Google
Dani Montgomery13 August 2025Josh - JG Building & Construction PTY was our builder for our new bathroom ensuite, extra building works we needed etc. We could not be happier with the outstanding work that he did, managing all his trades on time promptly and his follow-up to detail was amazing. We honestly could not fault him at any level. Would highly recommend Josh and his company to do any work for anyone and we will be using him in the future. Dani & Chris MontgomeryPosted on Google
Anna Maguire14 April 2025Josh and JG Building did a major renovation for us (2.5 bathrooms, laundry, new flooring, wardrobes, new kitchen +++). We chose Josh due to his attention to detail when quoting that built trust. The whole job was completed in a short time frame, with great professionalism and no stress. With him managing all the trades we knew he would coordinate what needed to be done, when, and he did. We would highly recommend him. Should we ever do another house and renovation, we will be on the phone to him pronto!Verified by TrustindexTrustindex verified badge is the Universal Symbol of Trust. Only the greatest companies can get the verified badge who has a review score above 4.5, based on customer reviews over the past 12 months. Read more
OWNER & DIRECTOR
Meet Josh
Behind every project is Josh, a licensed builder with hands-on experience across residential construction and a genuine passion for delivering quality work done properly.
Josh built JG Building & Construction around a simple approach: honest communication, reliability and managing projects the right way from start to finish. From your first conversation through to project completion, you’ll deal directly with Josh and receive practical advice tailored to your project.
“I started JG Building & Construction because I wanted to provide homeowners with a better building experience, clear communication, quality work and projects delivered with care and attention to detail from day one.”
Get Your Free Granny Flat Estimate
Get in touch today for a no-obligation estimate. We’re here to turn your building dreams into reality.
Check out Some of Our Recent Projects
How much does a granny flat cost?
The cost of a granny flat can vary depending on factors such as size, design, site conditions and project requirements. Fill out the form below for a tailored quote based on your property and goals.
Can you build on sloping or difficult sites?
Yes. We have experience working on sloping blocks and challenging sites, providing practical solutions for these projects that require custom structural considerations.
Do you manage the project from start to finish?
We work closely with clients throughout the entire process, helping manage projects from planning and preparation through to construction and completion.
What areas do you service?
JG Building & Construction provides granny flat and residential building services across Sydney, the Central Coast and Newcastle.
Get A FREE Price Estimate
Simply fill in your details and a little about the project to get your price estimate