The laurels of Britain's tallest commercial building made of laminated timber are now owned by the Sky Telecommunications Corporation headquarters, with a 4-story Arup Associates building on the company's London campus. Romantically named Believe in Better Building according to the company's current slogan "Believe in Better", it was supposed to embody the main principles of the educational campaign of the same name: education, openness, cooperation, collaboration, variability, pluralism, manufacturability, care for the environment. According to the architects, only wood could become the material from which it was possible to create a space corresponding to these principles in the shortest possible time.
The most spectacular facade, the northern one, with a staircase rising along it, faces the main square. Upon completion of the reconstruction of the Sky campus, this square will become a place of attraction for people, the intersection of their routes from building to building and a kind of "auditorium" in front of the "stage" - this glazed facade through which the structure of the building is visible. The main staircase connects all floors: it not only serves as an interlevel link, but also visually reflects the openness of the building to the outside. The purpose of the staircase is not a "transit" (more utilitarian staircase-elevator nodes are responsible for this), but a place of the focal point of life inside and demonstration of it to pedestrians outside.
The modular grid of the wooden frame allows to accommodate this life and realize the conceived multifunctionality of the building with various premises - from rooms for classes with Sky Academy Careers Lab youth and classrooms for professional trainings to office open space. Numerous room configurations are formed by sliding partitions, which provide the high level of sound insulation required for a multimedia company.
In the interior, open wooden surfaces without cladding are used to the maximum: this became possible due to the absence of the need for additional layers of fire protection or sound insulation. Due to the large cross-sectional area of the supporting structures, their fire resistance limit is the required 60 minutes, therefore, processing, for example, in the form of a plaster layer, was not required. The two-layer construction of ceilings, in which the floor and ceiling are spaced in height, not only creates space for laying communications and electrical equipment, but also provides the required degree of sound insulation.
The load-bearing frame consists of glued wooden columns (mesh 6 mx 8 m), glued beams (8 m and 16 m each), cross-glued walls of staircase-elevator shafts, cross-glued CLT floor panels (length 12 m) and redistributing load of the truss wall on the 4th floor, which compensates for the absence of columns on the middle axis of the 3rd floor: this large unsupported space can be used as an office open space or a hall for public events.
The use of "two-span" 12- and 16-meter horizontal structures reduces deflection, vibration, increases the rigidity of the structure, accelerates the process of erecting a building by reducing the number of elements required for lifting and, therefore, provides significant savings: according to the estimates of the designers, the convenience of construction is one of the critical elements of cost reduction.
Since Sky is positioning itself as a "carbon neutral" company, that is, it claims zero CO2 emissions as its goal2, and the Arup Group, which includes the Arup Associates architecture firm, specializes in “sustainable” design, it is not surprising that their collaboration and the set of measures applied in the Believe in Better Building resulted in the building being rated “excellent” on the BREEAM scale. In addition, upon completion of the campus renovation, the facility will be connected to an existing trigeneration power plant (CCHP - Combined Cooling, Heating and Power), which simultaneously produces electricity, heat and cold, which should elevate the facility to the level of "outstanding". Arup estimates that the building has sequestered 1,200 tons of carbon dioxide. Wood waste from the production of its components was used in cogeneration plants that provide heat and electricity to the manufacturing factory.
To avoid solar overheating and at the same time make the most of natural light, only the northern facade is almost completely glazed, illuminating the space of the main staircase and the adjacent rooms, while the rest of the building penetrates through tall but narrow windows.
70% of the building is clad with 2-storey wooden cassettes with a thermal conductivity of 0.2 W / m² · K, which reduces the loss of heat energy per square meter to 3.58 kWh per year: this is 76% less than the standard "Passive House" of 15 kW ⋅h / m2.
The building uses a mixed natural and mechanical ventilation using air heat pumps and heat recuperators; in summer, adiabatic air cooling in the air handling unit works. The rooftop photovoltaic system, when connected to the campus trigeneration power plant, should reduce CO2 emissions by up to 40%.
Drinking water consumption for technical needs has been reduced by 62.89% from the BREEAM baseline for new facilities thanks to Arup's Flowstow system. The rainwater collected in the roof collectors is drained into the tanks in the bathrooms, and then fed through a filter directly on demand: the force of gravity makes the pumping station unnecessary, which frees up useful space and reduces the load on the power grid.
The development of the project of the building with a total area of 3850 m² took eight weeks, the preparation of working documentation - four: thus, already in three months from the beginning of the design, construction work began. According to the authors of the project, this speed became possible thanks to the close interaction of the team of architects, engineers, customer and builders, including through the use of BIM technologies. From the first sketches to possible problems during implementation, from the issues of reducing logistics costs to calculating the volume of carbon dioxide emissions, everything was discussed and revised together on the current 3D model. As a result of the union of BIM-design and wood construction technology, which involves the processing of wood materials exclusively in the factory and reduces work on the construction site to the assembly of the "constructor", construction was completed a month ahead of schedule, and Sky celebrated its 25th anniversary in a new building.
The construction cost was £ 25 million.
