Samuel Taylor Coleridge understood the restorative power of nature in contrast to the confines and demands of urban life. As he wrote in a 1797 poem, “for thou hast pined /And hunger’d after Nature, many a year, /In the great City pent”.
Such a desire to retreat and be close to nature is shaping some of the trends emerging in the design of contemporary treehouses, with a market steadily growing for high-end structures kitted out with all the mod cons.
“To design a treehouse is a bit of a childhood dream for each architect,” says Bolle Tham, of Tham & Videgård, an architecture firm which designed the structures for Treehotel, a Swedish company. “We wanted to create the basic idea of a treehouse hideaway, a refuge among the greenery of the trees.”
The Mirrorcube treehouse, designed in 2008 in response to a growing interest in eco-tourism, is one of five “treerooms” in the Treehotel, located on a forested hill close to the small village of Harads in northern Sweden. It is a lightweight, aluminium structure mounted directly on the tree trunk of a tall pine. The 4x4x4-metre cube is clad in reflective glass, making it almost camouflaged. The interior is made of plywood and the windows open up to 360-degree views. “It blends with its surroundings but at the same time stands out as an abstract piece, completely high-tech in contrast with nature,” says Martin Videgård, a founding partner of the company and architect for Treehotel.
Sussex-based Blue Forest is another company building on the treehouse concept as a high-end residence rather than child’s play den. The company was founded in 2003 by Andy Payne and today he runs the business with his brother Simon. Andy cut his teeth learning timber-frame construction in Japan and by working a conservation project in Kenya. Later, he worked at The Treehouse, a Scottish company which was commissioned to work on a number of high-profile projects such as the Treehouse at Alnwick Garden in Northumberland.
“We started out building treehouses . . . mainly as play structures for children,” says Simon Payne. “In the natural way, people see your portfolio and they want one a bit bigger, so it evolved like that for four years.”
The two brothers made a strategic business decision to focus on the commercial market, varying from treehouses designed for schools and the Eden Project in Cornwall to upmarket hotel suites strung out along a valley. In terms of private clients, this meant they could promote new aspects of treehouses. “We did a lot of job consultancy projects so we actively promoted those elements of the work to help people envisage what people historically considered a child’s toy – so that it could be taken more seriously,” says Payne.
According to Ann Gardiner of estate agents Savills, which is marketing a property in Scotland with its own Blue Forest dwelling, demand for treehouses is strong. “They are seen as a bonus . . . Certainly, there is a trend for really going for it, if it’s to be done at all. Of course, this means they need electricity, too.”
About 95 per cent of Blue Forest treehouses are made from timber. “We started targeting a high net worth client base and, in doing so, it made it more possible to look at much larger structures. They are unusual people who have an adventurous streak – often very open to pushing the boundaries,” says Payne.
Blue Forest treehouses – which are often two or three storeys – are very similar to timber-framed houses, constructed with a highly insulated building envelope. They also often incorporate cedar shingles on the roof because it is low maintenance and durable. “Around 90 per cent of what we do is bespoke. Joinery elements are made off-site. There is a lot of structural timber made on-site to fit around the tree,” says Payne.
The company has developed some prefab structures, such as an oblong cabin – or “eco-perch” – but its main focus is on more individual creations, ranging from its Quiet Treehouse to the Living the Highlife adult and child treehouses.
In the initial years, the average price for one of Blue Forest’s custom-made treehouses was £20,000. This has since grown to an average of between £150,000 and £200,000 for significantly larger, more developed structures with lighting, heating and technology, as seen in the Pool View treehouse. One of the company’s latest projects will retail for £1m upon completion. “It’s a beautiful, elaborate treehouse hideaway,” says Payne, “a two-storey structure with a loft level as well.”
However, acquiring planning permission for treehouse structures can be more complicated than one might expect. The author JK Rowling discovered this when she applied to build a structure for her children in her back garden in Edinburgh (the application was eventually approved by Edinburgh city council).
In most cases the local authority’s tree officer will be involved in an application and, in the UK, following an amendment to the Town and Country Planning Order, any permanent structure with a roof line of more than four metres, or any raised structure in a garden more than three metres above the ground, now requires planning permission.
A German company, Baumraum, is also moving into the high-end market for treehouses, with interesting results. Unlike Blue Forest, its tree-cabin structures are usually prefabricated in the workshop. The outside surface of the treehouse is built using larch wood but domestic timber is mostly used for the main structure.
The price of its treehouses range from €18,000 to €200,000 (in the residential and commercial market), but the company largely explores the concept of the treehouse as a space for retreat for its private clients, rather than as house to live in. This is demonstrated by its Meditation treehouse near Rome and the Plendelhof project in north Germany.
“Private clients are usually looking to create relaxing spaces, and they want to make a space for the whole family,” says Andreas Wenning, Baumraum’s architect and founder. “It could be a working space which is quite modern, or a place to meet people.”
Wenning has seen demand grow over the past few years, both on the private and commercial side, with commissions from across Europe as well as China and Brazil. “It’s tapped into the eco-living movement, but combined with modern comforts. I have lots of requests now – it is hard to meet the demand,” he says.
Wenning became involved in designing treehouses when he was working for an architectural firm. “I wanted to create a space for myself so I built my own treehouse 10 years ago. I wanted to be high up in among the trees. From there, I knew I wanted to work independently and [treehouse design] fitted my qualifications and passions.”
The health of the tree is also paramount to the company’s work – all the trees built around must be robust and healthy. If the tree is not deemed strong enough to bear the load of a structure, the company uses strong textile belts and adjustable steel cables. “If there is not a suitable, healthy tree available, it is possible to simply build the treehouse on stilts between the trees,” says Baumraum.
Some architects, due to certain practical concerns from planning permission to the health of a tree, choose to build around a tree, or to use trees as the centrepiece for a house.
“In the future, treehouses are likely to be spaces that occupy tree canopies, while their structure remains fixed to the ground, rather than to tree trunks,” says Andrew Maynard, an Australian architect, whose subversive Styx Valley Protest Shelter treehouse was built to highlight the threat to Tasmania’s forests.
“Though it is not a treehouse, our recent Moor House is designed so that the bedroom is surrounded by tree canopy. There is a huge, beautiful gum to the north and a lovely Japanese maple to the south. The bedroom is surrounded by foliage with no sight of trunk,” says Maynard.
Treehouses epitomise escapism and fun, and, whether they serve as an additional bonus to a property, or as the centrepiece of a residential estate, it seems likely they will become a more regular feature, both of the commercial and residential market.
“Bart Simpson’s treehouse epitomises what we love about them – a place of play, adventure and creativity,” says Maynard, “but also a place of retreat and solitude.”
Serena Tarling is a commissioning editor for House & Home
Architect’s tree project stands out
One tree project that has attracted plenty of interest is that of Polish architect, Konrad Wojcik, whose “Primeval Symbiosis” (a single pole house) received a special mention at d3 Nature Systems 2013, an architecture competition. “I wanted to create something . . . that could provide not only shelter but also all the needs of present-day society,” he says.
Wojcik, who is studying for a Master’s in architecture and design at Aalborg University in Denmark, says his project is “fully inspired by a tree” but is not a tree house. He had seen many projects that used trees as a supporting structure but were invariably small and not fully functional. He studied trees closely for the project, inspired by their natural role as shelters for animals. He believed his dwelling could offer a shelter for humans too, as well as conform to the latest definition of sustainable living. “Now that technology gets better every day, ‘passive’ is not enough. Now we are thinking and talking about ZEB (zero energy building),” he says. Some of the technologies that he proposed are still at the laboratory stage.
His idea was to create a dwelling on a single pole with no footprint on nature and that was fully self-sufficient. The designs show a triangular structure looming out of the forest that is level with the treetops. Built on four levels and designed to fit two to four people, all the furniture would be “cradle-to-cradle certified” – a new high standard set by Nordic countries for eco materials. Heating and energy would be produced via the sun and the ground. Opting not to use concrete or energy-consuming steel, glued, laminated wood would provide the primary beams, with stiff I-OSB beams as a supporting construction.
“Without the process of deforestation or building any technical infrastructure, it can be placed nearby any existing road that cuts through a forest,” says Wojcik.