Art and Design Building, Bedales School, Hampshire

Introduction

When Bedales School opened in 1893 it was the first co-educational boarding school, with close links to the Arts and Crafts movement and a philosophy which emphasised the importance of arts, craft and drama in a child’s development. It also established an ‘outdoor work’ approach, with a curriculum including gardening, tree planting and livestock tending. The new Art and Design Building by architect Feilden Clegg Bradley Studios is designed to be the creative hub of the school and a physical embodiment of its values and ethos.

The school and its 120 acre estate stand in an Area of Outstanding Natural Beauty on the edge of the South Downs National Park in the village of Steep near Petersfield, Hampshire, and the planning process required a design of sensitivity and scale that was appropriate to this beautiful rural setting. The estate is an eclectic mix of buildings, including a loose-knit cluster of traditional barns in which ‘outdoor work’ is taught. The new Art and Design Building is close by and reflects the traditional barn vernacular in both form and materials. It is L-shaped in plan, with four pitched roofs running at the west side and a fifth pitched roof turned at right angles. The L-shape creates a partial enclosure to a green space and a substantial and ancient oak tree. Materials are used in their natural state throughout; the standing-seam metal roof has clipped gables and walls are all clad with oak or larch.

On the ground floor heavy duty craft based design subjects such as woodwork and metalwork are taught alongside jewellery and fashion design. The pitched roofs provide ideal conditions for a series of north lit art studios on the first floor; they are open and interconnected to enable teaching and independent study for a wide range of group sizes and activities, including art, ceramics and print-making.

To the architect, one of the special qualities of the school was the close connection with the outdoors; as a result, all circulation is external, consisting of covered walkways which run along both sides of the building and double up as places to draw, paint, sculpt, or just relax and contemplate the landscape. This aspect of the design runs contrary to the ubiquitous ‘big box’ internalised model employed in many school buildings today.

The use of timber

Reflecting local agricultural tradition, the elevations of the Art and Design Building are all clad with timber. The long east elevation and the shorter north and south elevations are clad with a rainscreen of FSC certified, rough sawn Siberian larch, used in a playful manner to create multiple cladding types. The untreated larch boards are orientated vertically, horizontally, ribbed, and laid hit and miss; this contributes to a diverse range of patterns, shadows and transparencies over the elevations with the use of a single material.

The main entrance to the ground floor studios is on the west elevation, facing the oak tree.  Alongside this entrance is a staircase and external walkway which gives access to the first floor studios. The walkway runs the full length of the elevation and is screened with an open lattice of oak and larch, rising above the main entrance to indicate its presence to approaching students.

Timber is used internally, especially in the first floor studios. The two storey structure is steel-framed with soffits exposed on the first floor. The steel framed pitched roof structures span 8.4 metres, supporting a series of exposed timber joists. The architect was keen to avoid a plasterboard ceiling finish; instead acoustic wood fibre panels are used as the final finish; they slot between the exposed oak joists and improve sound reduction.

To sub-divide the open plan studio spaces the architect designed a series of moveable birch-faced plywood storage and display units, tall enough to act as display boards and with the lower parts open for storage of large drawings and portfolios. The extensive use of timber contributes to the barn-like feel of the interior and reduces the embodied carbon compared to other materials.

The lattice screen

Along the west elevation the four pitched roofs project along their gables to shelter the external walkway and the staircase which leads to the first floor studios. Delicately superimposed over the whole elevation, including staircase and walkway, is the lattice screen, a vast yet intricate tour-de-force in timber, extending along the four gables for nearly 36 metres.

The screen is supported by a steel frame which extends from the external wall and was erected at the same time as the main steel structural frame of the building. The frame consists of steel beams and columns which span 8.4 metres between the valleys of the pitched roof gables.

The lattice screen was fabricated in the workshops of Green Oak Carpentry in Liss, Hampshire, not far from the school. It is an oak diagrid, set at 95 degrees to follow the pitches of the four roofs and made up of 100 x 175mm oak members. The connections between these 121 oak members, all set at different and complex angles imposed by the diagrid, is a combination of traditional carpentry and modern jointing techniques. The oak-to-oak connections were generally made with single and double tenon joints, pegged with 19mm diameter oak pegs. The oak-to steel frame connections were generally made with steel brackets with projecting welded bars, bolted to the steel frame; the bars were slotted into predrilled holes in the oak, which were then plugged. The steel brackets are 20mm thick so that the oak members are spaced 20mm away from the steel structure to avoid oak to metal staining/corrosion and to allow clearance for the bolt heads which fix the bracket to the steel.

Because of the complex interlocking nature of the assembly, every single component of the oak diagrid (121 in total) was pre-jointed and pre-planned for assembly in a unique sequence. If this had not been followed the entire structure would have had to have been dismantled and started again from scratch. The diagrid was fabricated and laid out in the Green Oak Carpentry workshop and then taken to site and assembled.

The diagrid is clad with a series of vertical 94 x 50mm Siberian larch slats which are generally set 210 mm apart and fixed to the diagrid with torx-head stainless steel screws, set flush.

Oak was selected for its strength and durability and is used untreated. The Siberian larch was specified to be free of sapwood and, because of its origins in the Russian tundra and slow growth, is particularly close-grained and durable. It is intended to weather to a natural finish.

Sustainability

The Art and Design building has been designed to minimise the carbon footprint through the application of passive building principles, including renewable energy.

The use of renewable natural materials of sustainably sourced timber for cladding and wood fibre acoustic panels helps to reduce the embodied carbon in the construction. The lattice screen and the retained large oak tree give solar shading in the summer months.

Sustainable features include air-to-water heat pumps for space heating and hot water, solar controlled glazing and energy-efficient lighting. To capitalise on the benefits of thermal mass in what is otherwise a lightweight building, the concrete surfaces of certain soffits and floors have been exposed, contributing to a more stable internal temperature.

Awards

2017 RIBA Client of the Year Award

2017 RIBA National Award

2017 Petersfield Society Owl Award

2017 RIBA South Award

2017 RIBA South Sustainability Award

2017 RIBA South Client of the Year

2017 RIBA South Project Architect of the Year

Completion Date:

October 2016

Building Type:

School arts building

Location:

Petersfield, Hampshire

Client:

Bedales School

Architect:

Feilden Clegg Bradley Studios

Structural Engineer:

Andrews Newby Partnership, Momentum

M&E Engineer:

Silcock Dawson & Partners

Main Contractor:

E W Beard Construction

Joinery:

The Green Oak Carpentry Company Ltd

Timber Supplier:

Bennetts Timber, Grimsby (larch), Granville Bois, France (oak)

Timber Elements:

external lattice diagrid, cladding, joists, studio furniture

Timber Species:

FSC Siberian larch, French oak Grade QPA

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