Sylva Foundation - New Offices
Located some 15 miles south of Oxford, the Sylva Foundation is an environmental charity working to revive Britain’s wood culture.
It cares for forests, to ensure they thrive for people and for nature, and supports innovation in home-grown wood. Their activities are organised under four themes: science, education, forestry and wood
Land and Buildings
Sylva’s embryonic ‘Wood Centre’ was based around old corrugated metal farmyard buildings with adjacent land for afforestation. Their next step was to secure modern offices which would reflect their ‘wood culture’. But, like most charities, their finances were very limited.
Referal to BenfieldATT
In early 2015, Dr Gabriel Hemery, CEO of the Sylva Foundation, approached Benfield ATT for help and sponsorship in designing and building the Charities new offices. He had learned of their environmental commitments and record of service to the industry, especially via the Wales Forest Business Partnership and its Wood Knowledge Wales research, development and information dissemination activities, and felt they may see both community, industry & commercial value in assisting.
As specialists in all forms of timber buildings, Benfield first suggested that one of their Regal range of standard prefabricated office buildings might be suitable. In particular they suggested that their Viceroy Business Centre model would provide a suitable mix of offices with kitchenette and toilet facilities.
While acknowledging the spaciousness and potential suitability of the standard range, Sylva already had welfare facilities on site and felt that the space occupied by these would be more use if they could be incorporated into the rather larger office space that they were looking for. If possible they also wanted to use as much ‘home grown’ timber as possible to reflect their ethos and objectives. Using Benfield’s in house technical design facilities, it was therefore agreed to draw up a very bespoke alternative for the consideration of Sylva Foundation’s board.
Reflecting Sylva’s wish to exhibit as many different types of British timbers as possible, the initial proposals were based around a very contemporary cubist concept, with a large number of rectangular panels each displaying a different timber. However, both the board and the local planning officers expressed preference for a more conventional structure, reflective of its agricultural vernacular setting. It took almost 12 months of somewhat tortuous negotiation to eventually obtain all necessary approvals for the project.
Having already established the space, plan, and general building arrangement, the aesthetics of the design were revisited. To minimise excavation and other earthworks, the foundations had been determined as concrete pads with stub posts supporting a ring beam and timber joisted floor. This was insulated between the joists with 200mm of PIR and topped by tongue and groove sheet flooring as a base for commercial grade carpet tiles.
Post & Beam Superstructure
Likewise the original frame for the superstructure - an adaptation of Benfield’s ‘SolidLox’ modified post and beam structures – was infilled with factory insulated timber frame panels. Externally these were clad between the posts and beams with feather edge Douglas fir. Internally the panels were lined with skimmed plasterboard, leaving a service void behind this for electrical wiring. No plumbing was required.
To further reflect the rural / agricultural / forest industries nature of the building, it was decided to use a double hipped barn end roof, clad externally with cedar shingles to cover the roof. To optimise the sense of spaciousness within the building, vaulted ceilings were chosen, underlined with skimmed plasterboard on the bottom of the rafters. These were also insulated in between with rigid foam PIR sheet insulation.
Traditional Roof Trusses
To resolve the issues of providing support for the roof timbers without impinging on the open vaulted ceiling, the design made use of traditional mortice, tenon and pegged timber trusses. Fabricated off-site in Benfield’s factory, these were made from British grown Douglas fir, once again reflecting the preferred vernacular. They provide not only added spaciousness to the inside of the office complex, but also a welcome traditional feature, as well as being structural.
Ramps & Decking
To contain costs, Sylva opted to construct the external ramps and external balcony style decking themselves, using readily available timbers, decking and volunteer labour. The rear deck provides a spacious seating, meeting, and reception area, with open views over the land being planted out for forest and a community orchard. These areas are split into plots, each being sponsored by individuals who then have the right to visit and use them for picnics, etc. as the trees grow.
At the time of writing these remain somewhat of a ‘works-in-progress’ along with the timber skirts that remain to be fitted below the floor beams to mask the post and pad foundations.
Highly Appreciated Offices
Although it took considerable time to agree the final design and obtain development permissions, the technical design, structural engineering, factory fabrication and on-site erection were a relatively quick process. Occupied in spring 2016, staff have been faced with cold, wet and some very hot weather. They report very favourable impressions under all of these climatic variations.
To reflect the environmental concerns of both the Sylva Foundation and building providers, the offices had been designed and built to very high standards of insulation and airtightness. Although Benfield’s had expressed some concern that the offices – divided into a main office, directors office and small reference library for staff and visitors – could prove to be too hot and ‘airless’, judicious use of openings to create ‘cross flow’ ventilation has proved very acceptable.
Visitors too, comment most favourably upon the spaciousness, high vaulted ceilings and traditional timber truss features of the offices. Already schools, whose pupils have paid educational visits, are asking about the possible use of similar structures for classrooms, as are private individuals wanting to create home studios, offices and leisure buildings.