When Chisenhale primary school in East London had to grow in population without growing in size, it was faced with a problem: where would all the new children play? The task was made more challenging still given that there was no real budget to speak of.

The answer lay in a non-traditional double-decker playground and inspiring people and companies to give time, funds, materials and expertise. Asif Khan, who designed the playground, has two kids at the school and offered his services pro bono while the American Hardwood Export Company (AHEC) donated all the timber for free. The Parent Teachers association, among others, helped to raise funds.

Khan sought inspiration from projects in Sweden and Japan. Before embarking on the design he consulted the children for several months asking them to produce drawings of what they wanted to see done with the space. One child wanted a rollercoaster with lights and a trapeze; another a pond with a laser and an air cannon; another still a playground featuring barbed wire, a rainbow slide and a unicorn. 

Though refreshingly whacky and rather too ambitious for the lean budget and space at their disposal, the plethora of unbridled ideas and enthusiasm led Khan to realize that his structure had to be pared back as much as possible so it could be a 'blank canvas' that led to different types of play. 

He therefore created a raised timber longhouse (made of thermally modified and highly durable vertical tulipwood slats that will turn an elegant silver as they age), with a hill and an undercroft below covered in recycled tyre mulch to create a soft and hospitable landscape. The structure offers six ways up and down, two slides, three nets and a variety of grips and ropes for climbing. 'It's a piece of architecture in a sense but the real programme comes from the kids,' says Khan. 

And the children are using the playground in unexpected ways says Khan. The hill is especially popular. 'Some children lie on it and sunbathe because it warms up with the sun," he says. "Another group of kids just likes to hang out really deep underneath the structure. It's a comfortable and cosy space but they are high up so they can also survey the playground.'

The structure can easily be added to and there is a plan to extend it to join the nearby bike shed roof. 'The roof could be planted as a garden and the shed could become an outdoor classroom,' says Khan. 'There's a definite feeling that this thing can grow.'