Home Extension Architects Melbourne

The bigger house without moving, designed by a registered architect on a fixed fee.

A home extension is Melbourne's favourite answer to an awkward question: how do you get the bigger house without giving up the street, the school zone and the garden you already have?

FIXED FEES | 35+ YEARS | 59+ HERITAGE APPROVALS | REGISTERED ARCHITECT (FRAIA)

THE BIGGER HOUSE, IN PLACE

Done well, an extension is not added floor area. It is the whole house replanned around how your household actually lives, with the new work carrying the light and the old work keeping the character you bought.

BY Projects Architecture has been drawing that answer for 35+ years across 400+ Victorian projects. The stock this page serves is most of Melbourne: terraces and cottages on tight inner lots, Federation and interwar homes on middle-ring blocks with room to move, and postwar houses whose plans owe nothing to how families live now. Registered architect Barbara Yerondais FRAIA leads every engagement, and the fee is fixed before design begins.

35+

YEARS

400+

PROJECTS

59+

HERITAGE APPROVALS

WAYS TO EXTEND

The four ways
Melbourne homes grow

Back

The classic rear extension, with kitchen, living and garden connection rebuilt where the lean-to was. The right answer when the block has depth and the sun cooperates.

Up

The second-storey addition, right when land is the constraint and either the outlook or the plan argues for height. It is decided in section drawings, in setbacks, massing, overshadowing and neighbour sightlines, long before it is decided in floor plans. On tight blocks it is a particular specialism of ours.

Sideways or wrapped

Side infill and courtyard captures that mine the space an old plan wastes. Often the cheapest square metres on the site.

Behind the face

On protected streets, the extension that stays invisible from the frontage while doubling the life behind it. Our Port Melbourne shadow-line project is the worked example: a hidden storey the front of the house never admits to.

PROOF

Extensions on
the record

The register tells the range. A substantial extension plus second dwelling won through the tribunal on a restrictive Port Phillip heritage site. A 1960s triple-fronter in Altona renovated and extended into a modern family home. A major extension to an 1880s Carlton townhouse, approved in six months. And the shadow-line project that added a concealed storey to a Victorian workers cottage.

Different blocks, different councils, one discipline.

Out of room, but not out of love with the house?

Book a feasibility session and the honest extension answer gets drawn in an hour.

BOOK A FEASIBILITY SESSION

APPROVALS

Permits,
told straight

Most substantial extensions need a planning permit, and all of them need a building permit. Neighbourhood character, setbacks, overshadowing and overlooking are the usual battlegrounds, with heritage overlays adding their layer where they apply.

We design for the assessment from the first sketch, use pre-application advice where councils offer it, and program the 60 statutory days plainly, including the points where the clock pauses.

PERFORMANCE

The extension is where
the house gets warmer

An extension is the one chance most homes get to fix their physics. The new work can be oriented to the sun the old work ignored, glazed for light without the heat penalty, insulated properly, and sealed against the draughts that make a period house expensive to heat.

Barbara lectured building science for around a decade, and it shows in where the windows land. Comfort is designed at sketch stage, when it is nearly free, rather than added afterwards, when it is not.

OUTCOME

What an architect-led
extension buys

A plan that reads as one house rather than old plus new. Light where the family actually lives. An addition the street accepts, which is what makes approvals move. And cost certainty: across BY Projects' delivered work, substantial extensions have started around $1 million, portfolio examples rather than a price guide, with your project priced at feasibility and the fee fixed from the start.

COMMON QUESTIONS

Extension questions,
answered honestly

How much does a home extension cost in Melbourne?

Across BY Projects' delivered work, substantial extensions have started around $1 million, with renovations from approximately $250,000 to $570,000. These are portfolio examples rather than a Melbourne-wide price guide: scope and site drive the real number, and the feasibility session gives you one for your project.

Should we extend up or out?

The block decides. Depth and sun favour going back; tight land and outlook favour going up. A second storey is judged in section drawings before anyone falls in love with a floor plan, and feasibility answers it for your house specifically.

Do I need a planning permit for an extension?

Usually, for anything substantial. Character, setbacks, overshadowing and overlooking all get assessed, plus heritage where an overlay applies. We confirm your property's exact position first and design for the assessment from the start.

Will an extension work on a heritage-listed house?

Frequently, and it is our deepest lane: 59+ heritage approvals, including extensions won on highly restrictive sites. The craft is adding boldly behind what the street values.

How long does an extension take?

Design and approval typically run in months rather than weeks, and construction adds to that depending on scope and your builder's book. We map the realistic program at feasibility and keep it current as it moves.

LOCAL KNOWLEDGE

Useful Victorian
resources

Planning Victoria

Permits, setbacks and overlays.

Victorian Heritage Database

Check your property before you plan.

Extension articles

Extension types and second-storey additions.

START THE CONVERSATION

Start with the
house you have

A full one-hour feasibility session with Barbara, in person: your house, your block, the four ways it could grow, and a clear recommendation. She sketches while you work through budget, logistics and planning timelines together, and the drawn concept is yours to keep. No obligation.

An extension enjoyed next Christmas is being drawn this one. Approvals and builders take the year in between.

Start the Conversation

Every project begins with a deep inquiry into site, heritage, and vision. Let’s discuss the strategic potential of your next work.

SCHEDULE A FEASIBILITY SESSION →

A PRELIMINARY CONSULTATION TO EVALUATE HERITAGE CONSTRAINTS, SITE POTENTIAL, AND PROJECT FEASIBILITY.