The team

The people behind the work.

Kosta, founder of BuiltIN Studio

Kosta Hatzis

Project Director & Founder

Kosta Hatzis is a Melbourne-based Project Director and Development Executive with over 30 years across building design, construction and property development. He has led and delivered a portfolio exceeding $309 million, including apartment and mixed-use developments valued up to $41 million, alongside townhouse, industrial, commercial and high-end residential projects.

He works across both sides of the table. Developer-side strategy and builder-side execution, in the same person. That is what allows BuiltIN Studio to align feasibility, design, buildability, programme and commercial outcomes from day one of a project through to permit approval and construction readiness.

His areas of focus are feasibility assessment, design and documentation coordination, planning and building permit pathways, procurement strategy, contract administration, and risk management in complex Melbourne development environments. He leads multidisciplinary consultant teams of planners, engineers, building surveyors and specialists across every BuiltIN Studio engagement.

Jenny, interior design lead at BuiltIN Studio

Jenny

Interior Design Lead

Jenny is the Interior Design Lead at BuiltIN Studio. Years spent transforming, styling and renovating her own properties shaped a deeply developed understanding of how a space should not only look, but feel. She formally entered the interior design industry on that foundation, and has worked alongside the studio since 2022.

Since joining, Jenny has played a key role in a number of innovative residential transformations, contributing to projects that balance architectural intent with warmth, functionality and individuality. Her ability to coordinate materials, textures, tones and finishes with precision gives her work a depth and cohesion that consistently stands out.

Known for a sharp eye for detail and a highly intuitive approach to interiors, Jenny has a natural ability to uncover the potential in a space and elevate it into something memorable. For her, great design is never just about aesthetics. It is about creating spaces people genuinely connect with.

The journey

Three decades, one studio.

A practice that has evolved with the industry — from on-the-tools building, to integrated design and construction.

— 1995

Founded

Kosta founds the original construction business in Melbourne, focused on residential and small commercial projects.

— 2000s

Expansion

Major commercial and industrial clients including Cummins Australia, Captain Snooze (Manufacturing) and national retail.

— 2010s

Boutique residential

Established as a go-to studio for boutique apartment developers — Drummond Rise, Bellview, Swindon, Axis, The Huntingdale.

— Today

BuiltIN Studio

Integrated building design, town planning, permit documentation and construction support — Melbourne's south-east, working state-wide.

BuiltIN Studio — completed Melbourne residential development
The studio

Practical building design, backed by real construction experience.

BuiltIN Studio was founded by Kosta in the mid-1990s — first as a building company, then evolving over three decades into the integrated design, documentation and construction-support practice it is today. Across that time we've worked on everything from custom homes and townhouse developments to multi-storey residential, commercial premises, factories, warehouses and complex mixed-use projects.

The thread through all of it is construction. Kosta's background is on the tools and on the ground — operations, builder relationships, project management, and tens of thousands of hours actually delivering buildings. That experience filters into every drawing the studio issues. We know what's hard to build, what's expensive to build wrong, and what makes the difference between a clean handover and a stressful one.

What we believe about good design

Good design isn't a magazine spread. It's a building that gets approved, gets built within budget, and is a pleasure to live in or operate from a decade after handover. That's a higher bar than visual cleverness — and it's the bar we hold ourselves to.

We believe in being honest with clients early. If a brief, a budget and a site can't be reconciled, the right time to know that is in week one of feasibility — not month four of permit drawings. Our process surfaces those tensions early so that the project that gets built is the right project.

Who we work for

Private homeowners. Boutique developers. Major developers and listed corporates. Builders looking for a documentation partner who won't disappear when site works start. Investors and landowners feasibility-testing what their site can actually deliver.

Past and current relationships include national and international names alongside dozens of long-term Melbourne developer clients. Our work has been recognised across boutique apartment developments, premium custom homes and complex industrial premises.

Why “BuiltIN”

The name says the philosophy: design and build, integrated. Construction sensibility built in to the design from day one — not bolted on at the end as a series of expensive corrections.

Clients past & present

Trusted by names that know how buildings work.

A short, partial list of organisations we've worked with across residential, commercial and industrial sectors over the last three decades.

Captain Snooze CGHS Developments GT Heights Delfin Property Group
The network

One studio, broader capability.

BuiltIN Studio sits within a connected group of property and construction businesses — meaning we can support more of the project, with more depth, when it suits.

— 01

Property Development

Development advisory, feasibility and joint-venture capability for selected sites.

— 02

Architecture & Design

Full architectural, drafting and design capability across residential, commercial and industrial.

— 03

Construction

Affiliated construction operations for projects where end-to-end delivery is the right answer.

— 04

Steel Fabrication

In-house steel fabrication shop drawings and fabrication for industrial and structural work.

Founder's note

“We've spent thirty years figuring out how buildings actually get built. Our job is to put that knowledge into the drawings — so the next thirty years of your project goes a little smoother.”

Kosta · Founder, BuiltIN Studio

Ready to start your project?

Site address, sketch, brief, or just a question — we'll respond within one business day.