Dive into the sumptuous, layered richness of post-war Belgian modernism

When is something declared heritage? At what point does decoration become art? Today, in Belgium, the architectural remnants of the territory's post-war years are often overlooked or worse, destroyed. Yet unearthing their stories means discovering a treasure trove of architectural and artistic collaborations, while simultaneously laying bare an important part of the country's history.

This chapter dates back almost seven decades. A new dawn, a new day, a more humane world for all: those were the ideals and sentiments behind Expo 58 in Brussels. When the fair launched in the Belgian capital in April 1958, people had every reason to be optimistic: the Second World War was firmly behind them, and the future was looking bright. It was the era of health insurance, unemployment benefits, paid pensions, paid holiday leave, the rise of tourism, the rapid evolution of technology and, most importantly, the promise of a home for all.

A decade earlier, a new law had been passed in Belgium championing this very promise by providing direct subsidies and cheap loans to homebuyers. Although the idea of wider ownership had been around before, after the war ended, it became a reality for the majority of the population.

As the common expression in these parts goes: Belgians are born with a brick in their stomach. The saying has nothing to do with the indigestion that might befall you after eating one too many waffles, but instead means that Belgians are destined to become homeowners. And yes, that's still a main life goal for most of the country's population.

With its future-facing spirit, Expo 58 became the perfect showcase for the new materials and rapid technological evolution that were making their mark on architecture. We're not just talking about flashy statements of pavilions such as the Atomium; the newly built environment all over Belgium was a true reflection of that innovation. Post-war modernism was characterised by the use of economical materials, a modular and quicker way of construction, generally aiming to be more humane and imaginative in spirit. During the interwar period, modernism consisted of a mostly rigid design ideology, imposing rules and ways of living on its users. After the war, a new era of modernism promised architecture that catered to the modern man and woman's needs – fully equipped kitchens and bathrooms, for example. But it also proved modernism could – and perhaps even should – be fun.

Buildings could now be adorned with decorative details, such as colourful sandwich panels, quirky fixtures and mosaics. (These were often created by artists, but rarely can their names be traced – only in the case of longstanding artistic collaborations can these be easily tracked down.) These partnerships between artist and architect felt natural and almost expected at the time, as architecture education was then still part of the arts department.

Examples of quirky door handle designs include the boomerang, a quiet icon of 1950s Belgian modernism, and the typically Belgian ceramic or enamel version of this ubiquitous element. These small pieces were often bespoke and designed by local artists, either for a specific project and architect, or as a side job to bring in some extra money.

Because of their practical function, people hardly pay attention to them and, as with all unrecognised heritage, they are quietly disappearing. Thankfully, initiatives like Ceramic Door Handles Belgium are shining a light on this sector of Belgian design history by telling the stories behind the objects and thus preserving them for the future.

Such personal passion projects are often what keeps examples of post-war modernism from disappearing altogether. Few buildings of the period are heritage-listed, leaving the majority of the era's built fabric subject to their owner's wishes. As many of those homes are now changing hands, they are often deemed unfit for the future, old-fashioned or simply misunderstood – and therefore in danger of being irrevocably altered. It doesn't help that dwellings from the 1950s and 1960s have a particularly bad reputation: cheap materials, single glazing, zero insulation, the list goes on. And let's not mention the word asbestos (present, for example, in the aforementioned sandwich panels). Hailed as a revolutionary material at the time, and effectively changing the outlook and construction of buildings, it was soon recognised as a health hazard, but nevertheless used until the early 1990s. It is important to note, however, that it is fully safe unless dismantled – the perfect motivation for conservation.

Perhaps the most playful architectural detail in use during this period was the humble tile. Coming in ceramic, marble or glass, and in different sizes, shapes and colours, tiles adorned not only floors or bathroom and kitchen walls, but, when used externally, became small artworks in their own right. The use of glass mosaic, especially, saw a significant growth in popularity. Praised for being more robust, easier to clean and non-water-absorbent (and thus stain-free) than their ceramic counterpart, they were a housekeeper's dream. Used externally, they carried the advantage of reflecting sunlight, giving the façade a vibrant quality.

Things became especially interesting when several materials were combined, creating an interplay of textures and colours in both exteriors and interiors. Prime examples are found in public buildings and shopping galleries, designed to give passersby something to admire. Of course, it helped that budgets for such projects were usually healthy, and the integration of art was often factored in from the start. The Ravenstein Gallery in Brussels, designed by Alexis and Philippe Dumont and officially opened in 1958, exemplifies this approach. Linking Brussels' Central Station with the museum of fine arts, Bozar, it had to bridge a 10m terrain drop. The challenge was resolved beautifully at the back of the gallery with an atrium (the original central fountain has now sadly disappeared) surrounded by winding stairs clad in mosaics and marble. At the entrance, monumental murals by architect Jean Ado Baltus adorn the ceiling.

A similar but much lesser-known example of such a mural can be found in the Blue Temple in the Belgian Museum of Freemasonry in central Brussels. Designed in the 1950s by architects who were also freemasons (and thus wished to remain anonymous), it's not publicly accessible through the actual museum as it's still in use today. Although the altar is typically 1950s in character, the trompe l'oeil pillars piercing the sky seem almost postmodern. Speaking of optical illusions, it seems fitting that we would end with a little-known mural by a Belgian master and the poster boy of surrealism.

As to be expected, public buildings with a cultural function contained even more art, and Charleroi's Palais des Beaux-Arts boasts an extensive collection of paintings, sculptures, ceramics and more, by artists such as Olivier Strebelle and Ossip Zadkine. The cherry on top, however, is a mural, La Fée Ignorante (‘the ignorant fairy'), in the congress room by René Magritte, who got the job after responding to a public call for an in situ artwork. Many of the artist's mysterious motifs, such as birds or leaves representing trees, can be traced in it.

Magritte once said that the function of painting is to make poetry visible, and by shining a light on the unsung Belgian post-war modernist architecture and its art, we can celebrate its quiet poetry, too.