28 August 1998

Constructive day

on shelter front

Exhibitors at last weeks

Agricultural Building and

Construction event

succeeded in attracting a

keen if limited audience.

Andy Collings reports

LIKE so many facets of the agricultural industry, the farm building business has seen both good and bad times.

Few exhibitors at the recent Agricultural Building and Construction event would dispute the fact that business borders on the thin side. But, as one company representative was heard to comment: "The real value of a building is in what goes in it – the cost of a roof and four walls is, by comparison, relatively little."

While that may be true, the vast majority of visitors to the event were taking some convincing. For many it was a window shopping exercise – albeit a useful one.

And while there was a distinct lack of construction companies, there were opportunities to glean advice and discover some of the latest developments, even if some were new versions of an old theme.

There is now, for example, a new mobile, free-range poultry house. While trying to avoid likening it to the once popular wheeled hen coup which successive editions of the much-esteemed Watson and More told farmers to move across fields to add fertility to their soils, one is drawn to the inevitable conclusion that it is just that.

Of course, the use of modern materials – insulated walls, hydraulically raised and lowered wheels and plastic floor mesh – has brought the system into the late twentieth century, and perhaps the millennium too.

Built by Associated Poultry Services, based at Crediton, Devon, and measuring 3.1m by 10m (10ftx33ft) – sufficient space for 500 layers – the fully-fitted unit costs about £5000 and should find favour with organically orientated growers.

But for those still sold on cubicle housing for their cows, Cumbria-based Quattro has a new foam mat called the Comfort Mattress.

Business development manager Ken Porter says the new design prevents water retaining hollows forming in the mat.

"The heavy duty foam sealed in a tough rubber outer always returns to its original shape," he maintains. "We offer a three-year guarantee against splitting or deforming."

Looking to expand the use of plastic mesh as a means of providing weather protected ventilation for buildings, the latest development form Galebreaker is the Agridoor. Designed to take the place of a conventional – and some would say potentially troublesome – roller door, the Agridoor comprises mesh sections which are raised and lowers by winding gear.

In a grain store, the system allows fans to be used effectively without having to keep doors open and allow vermin to enter.

The manufacturer also points out that the contact point between the bottom of the door and the ground does not have to be totally flat – a small plastic flap compensates for any irregularities.

Still with crop storage, Bristol-based Livestock Systems used the event to reveal its new pre-cast concrete floor crop ventilation system. Available as sections which are laid onto concrete floors, the main advantages include speed of construction and that the concrete is reputed to be of a higher standard than could be achieved when constructing such systems on-farm.

On a more historic note, Devon Earth Building Association (DEBA) members demonstrated how cob-built dwellings could faith-fully be maintained or renovated.

Cob is a mixture of subsoil (ideally 30% aggregate, 30% sand 30% fines), straw and water and such building material was used extensively in past centuries with a significant number of buildings still remaining.

Walls were formed by stacking cob on cob and compressing it. A slow task in that after each metre, stacking had to stop to allow the cob to dry out. And when the walls were completed an interval of up to a year had to pass for the whole structure to settle before the roof was constructed.

Latest development is to use a press to form bricks which, after drying, can be laid conventionally.

The DEBA claims that if looked after – no sealing coats of paint are applied, for example, such dwellings will last for centuries, as the many surviving cob-built houses in Devon are testament. &#42

Doors up to 6mx5m can be fitted with Galebreakers Agridoor.

The brickworks. DEBAs David Clark compresses another batch of cob to produce a 9kg block.