Hewitt Studios have recently completed a sustainable new-build workshop sporting an innovative and efficient ‘flat-pack’ timber structure.
The project is situated on the Holme Lacy campus of Herefordshire and Ludlow College and is designed to complement the nearby Straw Bale Cafe and Fast-Track Classrooms. It is used primarily for the maintenance of tractors and other agricultural machinery.
Unusually for an agricultural building, the workshop’s structure is formed in cross-laminated timber (as opposed to the more conventional steel). This is a pre-fabricated, sustainable and attractive material which was chosen for a number of reasons:
• It allows for a rapid on-site build (important as the College has a limited window of construction opportunity). • It is effectively self-finished (with Class 0 clearcoat), requiring no additional lining or applied finishes. • It gives the flexibility for services to be fixed anywhere, without the coordination issues normally associated with steelwork (welding of additional brackets, etc.) • It is carbon-sequestering, with only certified timber from sustainably managed forests being used (along with formaldehyde-free adhesives). The timbers are also reusable, recyclable and easily disposable (as biomass fuel) • It creates a better environment than a steel-framed workshop; the surface quality is warmer / softer and the acoustics are superior, with improved reverberation times. • It is cost-comparable with a conventional steel frame, once savings on site preliminaries, secondary framing, linings and finishes are considered.
Time and budget were both tight on this project - the workshop was delivered for a rate of just £1,500/m2 including specialist M&E equipment (e.g. vehicle exhaust extraction) and within a 6 month timeframe (of which approx. 5 days was spent erecting the timber frame).
As a result, the frame was designed to be as efficient as possible, using a standard CLT panel in square-cut sections, with simple (but elegant) connection details. The portal frame is formed from 200mm thick CLT columns and beams. The same material, in the same thickness, is then used for the wall and roof panels. This means that the whole building could effectively be cut from a single board type in one operation - true ‘flat-pack’ fabrication.
In order to maximise flexibility for the College, the fit-out is ‘loose-fit’ and capable of being easily reconfigured as the curriculum evolves and develops. All services are exposed and modular in format so that additional heating, extraction, etc. can be straightforwardly added to the base-build provision.
The choice of cladding materials has sought to make the most of the College’s natural resources. The western red cedar cladding was forested from the college’s 150 acres of woodland. This was cut to size on-site, by College contractors, just a few hundred yards from the building.
Elsewhere, variegated panels of FSC-certified marine plywood help to soften the building at low-level, whilst extensive use of polycarbonate glazing at high-level allows light deep into the pale timber interior.
The building has received an A-rated Energy Performance Certificate (EPC), and incorporates 12kW of on-site energy generation from a roof-top solar photovoltaic array, as well as Passivhaus level of insulation, low-energy light fittings and an efficient modular boiler system.