Architects around the world have been challenged to push the boundaries of modern wood building design in cities.

Wood manufactured Metsä Wood has launched a competition seeking suggestions as to how wooden extensions could add density to existing city buildings.

The company said that the world’s growing urban population and the rising demand of housing and interior spaces mean cities must start developing strategically and environmentally.

In a statement, it said: “Too often the proposed solutions show little regard for the existing framework of our cities, choosing instead to replace the old with new, at great environmental, social, and cultural cost. The greatest design challenge then, is not only to build new structures, but to build upon the existing fabric of our cities, knitting together old and new.”

Wood, the company argued, can provide the answer, as it is lighter, can be stacked taller and is better for the planet.

Architects entering the competition – which is called City above the City – must choose an existing and well-known city building, possible under threat of demolition, and show how the creation of additional wooden floor area upwards, and outwards if required, could produce a design solution.

Entrants have until 30 September 2016 to submit their designs, and the winners will be announced in October. The first place prize is €10,000, while the second and third prizes are worth €5,000 and €2,000 respectively.

Timber has many advocates as a design material, especially now that strong, fire-resistant wooden building materials are widely available.

PLP architecture, engineers Smith and Wallwork and researchers from Cambridge University recently presented conceptual plans for an 80-storey, 300m high wooden mixed use tower integrated within the Barbican arts centre in London, arguing that “people have a greater affinity for taller buildings in natural materials rather than steel and concrete towers.”