This Brisbane building might be the best of its kind in the country. Would anything like it be built today?

Few building types have stood the test of time like the public library.

Its role has long since expanded from book storage into being a community hub hosting a multitude of demographics, from parent groups to PhD students. Libraries are regularly cited among Gen Z as one of their true “third spaces”.

The State Library of Queensland (SLQ) might just be the finest example of its kind in Australia. What makes this building so successful?

The library we know and love today is a 2006 extension to the previous state library built in the 1980s as part of Robin Gibson’s Cultural Centre.

Reimagined by Donovan Hill and Peddle Thorpe Architects, it is double the size of the former library. This year marks two decades since its opening, and it’s worth reflecting what makes it one of Brisbane’s best public buildings.

The extension is nothing short of radical. Instead of a front door, you are greeted by a towering, bright green concrete wall nearly five storeys high, capped with a copper-finned crown. It gives nothing away about the inside.

Visitors enter by passing through a small gap beneath the fortress-like exterior which appears as a narrow band of shadow.

Imagine trying to convince a room full of suits this was a good idea.

The architects were in fact using simple ideas gleaned from our well-loved Queenslander homes, scaled up to a city size.

If you grew up in Queensland, you’ll know that summer temperatures peak in the middle of the day. You’ll probably retreat to the shadiest part of your house, away from sunny edges. And it’s probably a living room with a breeze passing through open windows from shaded verandah spaces.

Before the invention of air conditioning, homes were built to deal with climate in other ways, and much of what defines SLQ’s architectural legacy is borrowed from these learnings.

At the library, tough exterior walls protect a central five-storey atrium hidden in the belly of the building – a public version of your shaded living room.

This type of space does many things for a city. It is a place to hang out with no real purpose – you don’t need to buy a drink, you don’t even need to use the library. It is simply a space to be – and most importantly, it protects you from the heat.

The success of this particular “public living room” has a lot to do with its edges – lined with generous concrete and timber plinths that turn into steps and seats before folding into small tenancies and children’s play spaces.

Above it all hovers the bright-green beacon, transforming these outdoor meeting spots into shady undercroft spaces.

Public living rooms are difficult to master. If there are too few people nearby it’s spooky to visit on your own; too many and you lose the desire to wander and rest in peace.

One of the reasons libraries withstand this push and pull is because they are a seven day a week tenant – acting as a passive form of safety. But simply putting a large space in the middle of a floor plan is not enough to make good architecture. What else is at play here?

There is a distinct lack of hierarchies given to the multiple entry points of this building.

The low ceiling height of the main entrance contrasts sharply with the towering atrium – a trick that architects use to make each subsequent space feel more dramatic.

If, however, you approach the building from the side, you’ll find yourself walking through a triple- height portal that connects the Gallery of Modern Art to the Queensland Art Gallery.

You can also enter through the cafe or walk around the ground floor without ever setting foot in the library itself. These multiple and overlapping entries give the overall effect the building is full of holes, to quote architectural critic Naomi Stead.

Like any other thing full of holes, this is known as a porous building. Similar to a sponge absorbing water, the holes in this building allow the public to fill in the blanks.

The building does not dictate movement through a set of closed doors. It acts as a shaded landscape to wander around, rather than a building to be entered.

It is a testament to the architects who produced such sophisticated public space, unique in its brutal appearance yet aesthetically cohesive all the way down to balustrade details, stitched into an existing building. It also functions seamlessly.

It has enjoyed two decades of successful events, lectures, film screenings and exhibitions all on top of being a perfectly functioning library.

When will we see this same kind of investment in a public good again? And where? Can we afford to only build this type of amenity in the inner city? As Brisbane continues to rapidly grow, supporting community infrastructure will be a mark of a great city, not just a good one.

At least we have this world-class precedent to show us what to ask for.

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