Timber might be an ancient building material, but as these eye-catching projects demonstrate it readily combines its natural versatility with engineering innovation to create a future-proof construction solution
They call it the New Town; well, it was new when it was built in the 18th century but it’s getting on a bit now, so it requires that special care and attention to maintain what has become a cherished aspect of Edinburgh’s urban character.
The place is a renowned UNESCO World Heritage site, but it’s no architectural heirloom carefully kept to one side for safekeeping, but an integral and fully functioning aspect of Edinburgh’s living present.
The New Town, along with the Old – its 16th century counterpart – are also proving grounds for the most ancient construction material of them all – wood. In fact, not simply wood; along with a host of projects the world over, architects, manufacturers and timber specialists are demonstrating the capabilities of timber modified and engineered for the physical and aesthetic demands of the 21st century.
It’s in the New Town where Morgan McDonnell Architecture got together with Russwood for the redevelopment of prestigious Grade A listed offices at Charlotte Square. The 17-month project included rebuilding parts of the existing townhouses, as well as the creation of a new four-storey office building to the rear of the existing properties.
The architects opted to use timber cladding for the newbuild portion of the project, and this is where Russwood comes in; the company is a distributor for the modified wood, Accoya, which was selected because of its dimensional stability, its colour fastness, and its ability to resist weathering.
“Charlotte Square is one of Edinburgh’s most distinguished addresses,” said Anthony McDonnell, of Morgan McDonnell Architecture. “We wanted to use timber cladding to reference the historic materials characteristic of the lanes of this area, and using wood allowed us to add colour and texture to the thoroughfare.
Given the dimensional stability of Accoya, we knew it was perfect for such a prestigious location, and we have had some really positive feedback from our client, civic stakeholders and visitors.”
Accoya is manufactured by Accsys Technologies using its proprietary acetylation technology. The modified wood has gained a reputation for its sustainability, its versatility, and its dimensional stability and durability in a wide range of uses.
“Having worked with a range of timber products over the years, I was confident that Accoya would provide the Charlotte Square development with wood which would withstand Scotland’s toughest weather and still keep its aesthetic qualities. Accoya is a product which reflects the status of such a development, and comes with sustainability and quality at its heart,” said Russwood’s John Russell.
Naturally, to hear this kind of talk from the people using its products on location, as it were, is a satisfying aspect of a job well done for Accsys Technologies. Indeed, the architects liked it enough that they opted to use Accoya on their own premises.
Morgan McDonnell specified the material for use on their new offices in Edinburgh’s Old Town, on Advocates Close, near to the castle. This was part of a wider redevelopment of the 16th century site, and they used Accoya for external timber louvre assemblies on a selection of the building’s windows.
“Accoya is consistently specified for the highest-quality construction products in the UK, and these examples in Edinburgh’s Old and New Towns really show why Accoya outshines its competitor wood products,” said Bryan Crennell, the company’s director of sales and marketing.
“Independent tests demonstrate the stability, durability and consistent quality of Accoya time and time again, and this is the reason Accoya has proved so popular with architects and construction specialists not just in the UK, but world-wide.”
While the Edinburgh projects exploit the hard-wearing but aesthetic qualities of Accoya, a project in Amsterdam demonstrates its structural strengths.
Fagelcats is a complex of 22 apartments and four sheltered homes with 24-hour on-site care designed to meet the needs of elderly people, and more specifically those living with dementia, to live as independently as possible. At its heart is a garden pavilion which connects two five-storey buildings together, and is said to provide a “natural and peaceful escape from the densely populated city”. The aim is to create a space where people can relax in a calm environment which encourages a “sense of friendship and community”.
Accoya was used extensively in structure of the buildings, but also for columns, decking and window frames. The wood design was created to respect the surroundings of the city’s World Heritage canal ring and provide a modern interpretation of Amsterdam’s architectural style, according to architect Liesbeth Janson.
“Accoya gives Fagelcats a soft and natural appearance, which is intended to encourage a sense of calm and peacefulness amongst the chaos of the busy city, and this superior quality made the wood specification an easy decision,” she said. “Importantly, though, Accoya’s strength, durability and low-maintenance requirements were also key, as were its incredible sustainability credentials and its Cradle to Cradle Gold level certification.”
Crennell added: “From an architectural perspective, Fagelcats is an outstanding example of the way in which Accoya can be used to regenerate built-up areas, providing sustainable and durable buildings that remain sympathetic to existing infrastructure. It is also an example of the way in which material such as Accoya can respond to the needs of end-users, with aesthetic beauty and a natural appearance that adds the finishing touch to projects such as residential developments.”
Laminar education You might say the next two projects are teaching a few lessons about what it’s possible to achieve with cross laminated timber (CLT) construction, especially when it comes to factory-made modular techniques – that’s because they’re both schools.
“CLT stands for quick and clean construction,” said Herbert Jöbstl, SVP of Stora Enso Building & Living in Central Europe. “The high degree of prefabrication reduces construction time. Dust and noise exposure are reduced and it saves costs.”
The company is manufacturing and supplying CLT panels for the construction of 44 new primary school classrooms being built in the Austrian city of Vienna, with the aim to have them all completed by the end of 2015. Timber is claimed to have a beneficial impact on the well-being of the children who learn and play in the school’s environs, in addition to its low-carbon credentials, and the speed and quality control brought about by its modular off-site production.
The first classroom annexe was put together at a school in Vienna Penzing, on Karl-Toldt-Weg, with construction timed for it to be opened for the beginning of the new term.
The solid CLT panels were prefabricated in Stora Enso’s factory, tailored to ensure the gaps were in place for building equipment, heaters or windows, thereby minimising site waste. The room modules themselves were assembled from the panels at the neighbouring Stugeba Mobile Raumsysteme GmbH factory.
Finished rooms were shipped to the site for installation. The result is a greatly shortened build-time for the project. “Our room modules are versatile,” said Jürgen Sturmer, managing director of Stugeba Mobile Raumsysteme GmbH. “They can be combined and assembled in next to no time. This is of great importance for commercial buildings such as offices, hospitals or schools.”
The UK is no stranger to the benefits of timber in the built environment, and a project in the London Borough of Hackney has put Stora Enso’s CLT products to work in the construction of a special education needs (SEN) school.
Ickburgh PMLD SEN School is built to accommodate 150 pupils, aged between 2-19 years, who have profound and multiple learning difficulties. Along with its classrooms, a core house provides centralised and specialised services: medical care, a specially equipped sensory room, play areas and hydrotherapy pool. It is built to feel like a ‘home from home’.
Unusually, it is built to three storeys – they are more commonly single storey structures to allow easy access and circulation of wheelchairs, beds, and other specialist equipment, but this being London land is increasingly at a premium, calling for clever design to accommodate these requirements above more than one level.
These design challenges were address by Avanti Architects, while the school was built by main contractor McLaren Construction, working with specialist timber engineers, Eurban. The CLT superstructure was made from PEFC certified Austrian spruce and pine sourced and manufactured by Stora Enso Building and Living.
“Building with CLT provided a significant reduction to the construction programme and the project was delivered 20% faster and provided a 2% saving on cost against the project value,” said a spokesperson for the project. “In addition to its speed and cost saving benefits, the structural spanning characteristics of CLT lent itself to the very cellular layout of a special needs school.
“As a profound and multiple needs school, Ickburgh has extremely bespoke issues and a system build type of school is unusual for this level of need. Whereas generally the process would be to design the building then specify the system, at Ickburgh the system was specified and the school built around it.”
This article first appeared in the Winter 2014 edition of Timber & Ecoconstruct magazine