Time has been of the essence right from the start of the project to construct a new £4m, 1,500m2, mainly timber, bird observatory on Fair Isle.
In addition to all the usual “on time and on budget” requirements, there were a few other factors to consider, said project director Ian MacGillivray of lead designer Synergie Scotland.
“The new Fair Isle Bird Observatory (FIBO) replaces an earlier 40-year-old structure, which was demolished to make way for the new one,” he said. “The clients, Fair Isle Bird Observatory Trust, were keen that the observatory should be ‘closed for business’ for only one season. This would have been impossible using traditional construction methods, particularly given the short building season Fair Isle’s weather dictates, so we decided to use a modular system.”
For this system Synergie worked with AHW Building Solutions of Kirkwall, Orkney, which has developed and manufactures its own engineered timber, full panel, modular construction system, incorporating James Jones & Sons’ FSC-accredited JJI-Joists as principal structural elements.
FIBO is an innovative, sustainable, largely timber two-storey modular building. Designed to bring previously existing facilities up to the standards expected by today’s visitors, the new Observatory building includes a permanent house for the warden and his family as well as bird watching, commercial, conference, catering, retail and accommodation facilities.
Specially designed to withstand Fair Isle’s severe weather conditions, the building comprises 30 engineered timber pods, constructed from closed panels, fitted with the innovative Energyflo wall insulation system, which enables warm air to circulate in the cavity and be recovered using a heat pump. Floors, ceilings and walls of the pods use JJI-Joists extensively which, said MacGillivray, “provided an A-rated green material to maintain the sustainable credentials of the building”.
Roof fabrication incorporates glulam, which allowed large-span openings where two or more modules were to be joined to form public areas.
Given the exposed location, external cladding for this building was key and a highly durable laminated timber product called Triboard (also supplied by James Jones) was specified for the external walls. This incorporates a layer of spruce sandwiched between two boards of Siberian larch and, in this case, was supplied in 27mm-thick, 5x2m sheets.
“Triboard was supplied to comply with the client brief for minimal external maintenance,” said Brian Robertson, general manager of James Jones Timber Systems Division. “It’s a great product which uses untreated Siberian larch; this grows very slowly in cold climates so it’s very dense and durable – ideal if you want something low maintenance which can withstand the severest weather. And, of course, it’s a highly sustainable product.”
Cladding on the roof comprises Metro, a high performance metal tile which offers a 45-year guarantee. The roof design also incorporates 5kW of photovoltaic tiles for energy generation.
With Synergie driving the design and permissions, and AHW the pod manufacture and erection services, an impressive build schedule was set – and met!
Eight months was spent on the funding, design and permissions process – not least of which was getting building control approval for the Energyflo insulation system. Work on site finally started in July last year when demolition began. It took five months to complete demolition, put in new foundations and transport (in threes and by sea) and erect the 30 engineered timber pods.
Despite significant delays with heavy seas and ferries having to turn back, the actual shipping and erection of the modules were successfully carried out over a 14-day weather window and the building was wind and watertight by September.
Six months remained in the contract for interior fit out and landscaping and, despite what Ian MacGillivray describes as “the major challenge of logistics when you need to transport all your supplies to an off-shore site”, the building was successfully handed over in early May this year.
The Pod squad
AHW Building Solutions has been using prefabricated construction techniques since 2004, building up a considerable expertise – and its own innovative full panel and pod construction system – along the way.
“We have recognised that faster, factory-based construction is the way to go,” said Terry O’Hara, AHW’s managing director. “We feel it’s only common sense, delivering a better, more sustainable product and minimising handling on site.”
AHW has been using James Jones’ FSC-certified British manufactured JJI-Joists as the principal structural elements in its system since 2005. “We share James Jones’ commitment to sustainability and innovation,” said O’Hara.
Using pre-insulated closed panels, AHW has developed a successful four-pods-to-a-house method – two pods upper floor, two pods ground floor, for a two-bedroom, four-person house, which has been successfully used in a number of affordable housing projects. The pods come fully fitted with insulation, decoration, windows, doors, electrics and plumbing.
AHW’s system was adapted for the design and manufacture of the pods for FIBO. Using the services
of RTC Timber Systems in Elgin Morayshire to manufacture the glulam-rimmed, timber frame wall panels, these were manufactured to stringent standards.
“These wall panels needed to be very precisely manufactured, as the Energyflo insulation specified must be airtight to be effective and is only friction-fitted into the panels,” explained O’Hara.
Once completed, the panels were delivered to AHW’s facility in Kirkwall, where they were assembled into complete pods, ready for transport by sea, on the 12-hour journey to Fair Isle.
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The completed observatory |
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Weather caused delays but the 30 pods were shipped and erected in 14 days |
