EAST of England-based contractor Haymills has begun construction work on what will be one of the “greenest” warehouse and distribution facilities in the country.

EAST of England-based contractor Haymills has begun construction work on what will be one of the “greenest” warehouse and distribution facilities in the country.

The new £5.8million facility, being built for brewer Adnams just outside its home town of Southwold, not only involves advanced environmentally-friendly building techniques but is also green in the literal sense, featuring a grass-like roof to minimise its impact on the landscape.

Among the materials being used for the walls of the 4,400 square metre warehouse are hemp, lime and chalk blocks, which offer a range of environmental benefits in terms of their manufacturer and their performance once in use.

Less energy is required to produce the blocks compared with conventional concrete and, while the high percentage of lime and stone dust aggregate required to give them the necessary strength limits their thermal performance, this is offset by the insulation qualities of a hemp and lime cavity infill.

The two skins of blocks and the infill mix should, with the additional feature of double doors to restrict the amount of heat entering or leaving the building, create a constant warehouse temperature of 11°C - just right for beer storage without the use of heating or cooling plant, so making the facility highly energy efficient in use as well as construction.

Further advantages of using hemp are that it allows the walls to “breathe”, so helping to prevent damp, and “lock ups” carbon dioxide by absorbing it as grows. Similarly, the lime also absorbs carbon dioxide as it sets.

Another unique aspect of the project is the use of 40-metre Glulam (glued and laminated wood) beams within the roof structure. The beams, thought to be the longest ever used in Britain on any construction project, will over-hang each side of the building, so offering shading which will also contribute to temperature control inside.

The beams, the wood for which is from a sustainable source, are being imported from Denmark and will make their way to Lowestoft via sea before being transported - with a police escort - by road to Southwold.

Finally, the roof of the new building will be formed of Sedum, a living “carpet” of thick fleshy plants and grass - grown in Suffolk, near Mildenhall - which will provide not only a structural and aesthetic benefit, but will reduce energy costs and remove carbon dioxide and other pollutants from the air.

As a result of the warehouse's location in a former gravel pit, the green roof will effectively camouflage the building, so minimising the impact it will have on the view for passers by.

In addition, solar panels located on the roof will provide 80% of the operation's hot water supply and rainwater stored in the Sedum will be “harvested” and recycled for use inside the warehouse and for washing vehicles. Water from a septic tank will pass through reed beds, making it pure enough to return to nearby ponds.

Architect Ralph Carpenter of Bury St Edmunds-based Modece Architects has been championing the benefits of hemp in his home village of Hartest, which now has a number of hemp houses, but the combination of materials being used in the warehouse project is unique.

Adnams, the design team and Stowmarket-based Haymills hope that it will lead in due course- following an independent assessment -to a Building Research Establishment Environmental Assessment Method (BREEAM) Excellence Rating for the building.

The scheduled 42-week construction project should see the new facility become operational in September this year. It will replace the current, much smaller, distribution centre in Victoria Street and - together with a refit of the brewery itself which is already under way - will make Adnams one of the most environmentally efficient brewers in Europe.