Wooden box shelves and planters populate the gridded metal framework installed around the perimeter of this cafe in Beijing by design collective Penda (+ slideshow).

Penda – who recently spoke to Dezeen about the revival of bamboo architecture – came up with the modular furnishing system in response to a brief from Beijing property developer Hongkun for a design concept that could be applied to branches of its Home Cafe throughout China.

Based on the idea of creating "spaces to breathe in heavily polluted areas of China", the designers incorporated air-purifying plants and herbs that create fragrances to complement the smell of brewing coffee.

"The cafe will welcome people to come in not only for quality coffee, but also to enjoy a green oasis in the midst of a polluted city," said Penda.

The wooden planters are supported by a structure made from ribbed steel bars, typically used in the laying of reinforced concrete.

The designers repurposed the pre-used steel bars by welding them together into cubic frames, creating modules that can be reconfigured to divide the space in different ways.

The resulting structure separates the cafe's open seating area from cosy sofa spaces, and incorporates the serving counter and tray collection points.

"The structural grid offers a space, where various cubic elements can be implemented," said the architects. "By organising the cubes, the modular system allows a flexible assembly for different occasions."

Low-maintenance plants – including spider plants, sword fern and Marble Queen – fill some of the boxes, while vine plants and ivy are encouraged to gradually cover the metal frame.

As well as planters of different lengths, the black-painted structure contains cubic lights and boxes filled with books that can be interspersed in various densities, depending on the amount of privacy required.

Further modules that can be integrated into the units include steel versions of the planters, flat shelves and bare bulbs that stand upright or hang from horizontal surfaces.

Raw plaster walls around the periphery of the space are painted black and complemented by tactile leather sofas and the wooden surfaces of the boxes and other freestanding furniture.

The only colour is provided by the plants and scattered red versions of Jean Prouve's classic Standard chairs.

Another branch of the Home Cafe has also opened in Tianjin.

Penda was established 2012 by Chris Precht and Dayong Sun. Previous projects by the firm include an art gallery for Hongkun with undulating archways dividing the interior, and a doughnut-shaped house for an artist.