Designers build spiral staircase to the treetops

NEW YORK - People of all ages could soon be able to climb to the tops of trees thanks to two design graduates from London's Royal College of Art (RCA). They've created a novel modular step system that is attached to the trunk of a tree to form a spiral staircase, allowing anyone to walk up into the canopy above. Designers Robert McIntyre and Thor ter Kulve came up with the idea for CanopyStair as a final year project at the RCA for their Design Products postgraduate program. McIntyre said that the more they developed the concept the more they realized its potential for unlocking a largely undiscovered wilderness that everyone could enjoy. "I'm really interested in canopies of trees; they're the least explored eco-system on the planet -- we know less about them than the deep ocean. And they are kind of magical worlds. It feels like entering into a little secret when you climb up into them," McInytre told Reuters as he overlooked a full-scale 28-step prototype of the CanopyStair. McIntyre and ter Kulve experimented with about 15 prototype designs, before arriving at their most recent iteration. The CanopyStair comprises of an aluminum tripod frame, a coarse surface tread, handrail, and a ratchet strap that quickly fastens the step into place. The curved birch plywood of the step design draws on the techniques of aeronautical engineering -- something McIntyre has a personal connection to, as his grandfather was a chief engineer in the production of the famous wartime De Havilland 'Mosquito' airplane. Fundamental to the CanopyStair's design was the tree's wellbeing, with McIntyre and ter Kulve consulting arboriculturists at Hampstead Heath during the design process. The pair were adamant that the tree should be not harmed or damaged in any way; so the question of how to securely attach each step to the trunk presented a unique challenge. They found that thick neoprene pads mounted on the aluminum joints at each corner of the tripod frame did the trick. "Nothing is nailed into the tree. So there's a tripod that we strap to the tree and the feet of this tripod are made of neoprene, so they mold to the bark. So once you've taken the step down, there's no sign it was ever up. And it doesn't bruise the tree underneath the bark," said McIntyre. He added that the staircase has been rigorously safety tested: "It works fantastically well. Feels very safe; it is very safe. Each step takes the weight of three fully grown men - and you can only fit two men on [each step], I mean, testing it was a bit of a struggle." The pair also recommend that the CanopyStair not be erected in Spring when the tree is undergoing new growth. "You can leave the staircase up for a couple of months. It's advised to not put them up in Spring, because in Spring the tree grows its new ring, it expands. But the other nine months of the year you can just have it up there and really enjoy the full seasons of liveliness up in the canopy," said ter Kulve. He added that some trees - like the oak - are better suited for the CanopyStair: "Some trees are more likely to be damaged than other trees. For instance an oak has really thick, strong bark and is very well capable the kind of pressure that we're putting onto it." The team says that to build a seven-meter-high staircase would take two people about three hours, and just 30 minutes to take down. McIntyre and ter Kulve are now planning to develop the prototype further to make it a commercially viable product. - Reuters