With rising costs of materials and manual labour, it’s no surprise that Adelaide-based architect Jon Lowe says managing the budget is always the biggest challenge of any renovation.

But his recent Hortense House project, a 1930s Spanish Mission cottage in Glandore, proves just how much size matters when it comes to keeping costs down.

The clients approached him in 2022 with a vision to ‘future-proof’ their family home, on a budget of $450,000 for both the construction and design fees.

The brief called for a few key things: increase flexibility of their existing spaces, create more storage, and improve the connection between the living and the beloved backyard — a key focus for the owners as avid gardeners who love growing their own fresh produce.

At 135 square metres, the existing cottage was in ‘good condition’ with original details such as a delightful rendered facade, where twisted columns meet terracotta roof tiles and sweet signage of the house’s name.

However, at the rear, a lean-to housing the bathroom, laundry and sunroom blocked access to the gardens, making the accompanying kitchen feel ‘small and dark’.

Jon’s redesign left the front rooms largely untouched, focusing most of the budget on a new internal fit-out of the kitchen, bathroom, and a transformative 46-square-metre addition.

‘We reduced the footprint of the new addition to the minimum to fit the new living and dining space, by using the existing kitchen as the main circulation, and compressing the laundry and bathroom with an efficient design,’ Jon says.

Materials were also selected for their durability, insulation benefits, and cost-effectiveness.

In the new north-facing living space, double-brick walls, polished concrete floors and double-glazed windows offer new passive heating and cooling strategies, as the kitchen pairs Polytec Woodmatt joinery with all-electric appliances throughout — successfully eliminating the need for gas.

Terracotta tiles and pops of green reference the cottage’s original palette, as sliding doors open to the outdoor dining space with matching colours on the exterior and pergola.

Jon notes the renovation did require some compromise: ‘We initially had a solid roof over a large western deck with a concrete slab. We re-designed this to a half-deck, with the dining table on ground-level pavers, and a lightweight pergola above.’

Changing the concrete to a timber-framed deck, together with the reduced footprint, saved a significant amount.

‘It works out to roughly $4500 per square metre for the construction, which is on the low side for an architectural project in the Adelaide market,’ Jon says.

The new house spans just 157 square metres of the 870-square-metre block, giving precedence to the abundant gardens where the owners spend most of their time. And they say the result is even better than they imagined.

For anyone else wondering how to maximise a relatively modest renovation budget, Jon’s advice is to get clear about your intentions and what changes you need, versus what you might want.

‘Prioritise the areas that matter most to you — now and in the future — and discard unnecessary items,’ he adds. ‘Keep it simple.’

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