“…the structural design reduces energy use through wide spanning glulam beams sitting over dense walls built from lime hemp blocks…”

The central distribution centre for Suffolk brewer Adnams is a stunning example of sustainable design, widely hailed as "the greenest warehouse in Britain". The 90m x 45m building, the UK's first large commercial building built using lime hemp blocks, is covered by the largest green roof in Britain.

The 4,400m² column free space provides a constant cool beer-friendly environment of 11°C. The structural design reduces energy use through wide spanning glulam beams sitting over dense walls built from lime hemp blocks. Lime hemp has low embodied energy compared to conventional concrete, as well as high thermal mass. The 90,000 unfired blocks, each weighing about 19kg, and measuring 100mm x 254mm x 356mm, were produced by compressing limestone quarry waste (for strength) with hydrated lime, blast furnace slag, and hemp. Each block produces about one tenth of the carbon dioxide (CO₂) of a conventional concrete block.

Hemp construction effectively locks CO₂ into the finished structure. Hemp absorbs CO₂ as it grows, while the lime mortar and lime render absorbs CO₂ as it sets. Thus the Adnams Warehouse represents over 150 tonnes of carbon dioxide locked within its 8m high diaphragm walls. A building of a similar size constructed using more traditional methods would typically have generated around 600 tonnes of CO₂ emissions.

Above the curved Glulam beams sits the largest green roof currently erected in the UK, covering 0.6 hectares. The sedum removes CO₂ and other pollutants from the air while making the building blend with its rural setting.

“…the centre comprises two intersecting circular spaces roofed with domes…”

The Pines Calyx™ Conference and Training Centre, is an inspirational, ecologically sustainable venue located in the Pines Garden, an area of Outstanding Natural Beauty in Kent. The centre comprises two intersecting circular spaces roofed with domes. Constructed from materials harvested from the site, the centre exemplars low energy buildings in harmony with the environment.

The steeply sloping site meant excavating good quality chalk, which was recycled back into the main structure using a rammed earth technique. Timber felled on site was used for interior joinery and furniture. Local clay tiles from Kent clad the shallow vaulted dome roofs. Calculations indicated that maximum compressive stresses in a three layer tile vault 11m in diameter would be less than 1N/mm, making an unreinforced thin tile dome structurally viable. The master tilers built without formwork using procedures perfected by Raphael Guastavino in the 1880s in USA.

The first three layers of tiles were held together by fast setting gypsum plaster. A second layer was then begun, bedded on conventional mortar, with a third layer following close behind. Each layer used a different bond pattern for extra stability and strength. A final layer of mortar took the total thickness to 125mm.

“…the form of the minimal environmental impact, single-storey building was led by functional requirements…”

The Cockermouth School Eco Centre, a highly unusual multifunctional teaching facility in the Lake District, is an outstanding example of sustainable design. The form of the minimal environmental impact, single-storey building was led by functional requirements. The single storey front section is characterised by low walls and a significant span over the main teaching space, whereas the rear two storey section, which features a first floor conservatory divided into four climatic Biomes for botanical study, is tall, narrow and heavily loaded.

Using locally sourced materials where appropriate, the structure was designed to maximise insulation, using re-cycled materials, timber and lime (which has significantly less embodied energy than cement) whenever possible. Local contractors were encouraged to minimise waste during construction. The Eco Centre also incorporates a wind turbine, photovoltaic cells and rainwater harvesting. The building provides an eye-catching landmark facility for the local community.

“…designed with the ability to be dismantled and relocated or removed for recycling, a philosophy of reuse applies to the entire visitor centre…”

This innovative visitors centre set in the valley of Lower Dalby integrates the latest sustainable technologies in architecture, structural, civil, mechanical and electrical engineering services, using locally sourced materials where possible. The centre accommodates a wide variety of uses including a café, shop, gallery and community space. The building has minimal impact upon the valley and, upon eventual removal, will inflict no permanent damage to the area of special scientific interest site.

Designed with the ability to be dismantled and relocated or removed for recycling, a philosophy of reuse applies to the entire visitor centre. Even the foundations were designed as minimal excavation self-auguring piles that can be easily removed.

This unique facility in the heart of a working forest blends seamlessly into the landscape. It shows what can be achieved with a focused client, coordinated design team and awareness of environmental and ecological impacts of design choices at each stage.

“…an offset triangulated external frame to one side of the building, gives an asymmetric wide section while also allowing the curved roof to come into form…”

The 1,000 acres of Shorne Wood, North Kent include 100 acres of Sweet Chestnut for coppicing. Kent County Council decided to build a new visitor centre from coppiced Sweet Chestnut for the popular beauty spot.

Sweet chestnut grows for about eighteen years before licensed felling. As felling young trees produces straight but thin wood, laminating small laths was necessary to construct structural members. The building design developed around the size of curved and straight beams created using the in-house jig and lath unit of one of the few firms experienced in working with sweet chestnut.

A traditional Kentish cruck frame raised from 7m curved beams, the maximum length possible, would not have given the building the width or internal space required. Instead, an offset triangulated external frame to one side of the building gives an asymmetric wide section while also allowing the curved roof to come into form.