A traditional wooden structure and novel wall lining have been combined in four broiler sheds on a Gloucestershire broiler farm.
Geoffrey Phelps, who has been rearing broilers near Hartpury since 1989, spent nine years getting planning permission for his new 200,000 bird unit at Old Oak Farm.
To help offset some of the cost of this protracted planning process, Mr Phelps decided to use a wooden frame rather than clear span steel, saving about 20% on the project.
He chose Northern Ireland-based specialists E&C Fitzgerald, who have four decades of experience in timber-frame construction, and took their advice in incorporating Valeron AVA lining as part of the insulation setup.
Eamon Fitzgerald, managing director, designed a system to manufacture roofing panels on site.
The 3×1.25m panels contain 100mm of glass fibre and also a 25mm air gap, with the Valeron lining on the internal surface.
Once in place, the panel joints are sealed with tape to prevent air seepage. Without all this, another 50mm to 100mm of glass fibre would be required.
With this design, moisture transmission is virtually zero and remains so, despite regular pressure washing between flocks.
This avoids any need for a separate vapour barrier, while the almost anti-bacterial, easy-to-clean film surface helps maintain a healthy environment for the birds.
As well as the energy saving and the ecofriendly nature of the liner, the other benefit is in the high light reflectivity properties. Mr Phelps has installed rows of dimmable LED lights down the houses.
The lining achieves an even light spread across the floor and reduces energy consumption.
Mr Fitzgerald told Poultry World he believes the product had a real future in the poultry sector: “Valeron is very strong – it’s difficult to tear and is incredibly resilient. It is easy to apply and transport, allowing us to assemble our panels on site.
“In hot weather it keeps the temperature 1-3C cooler than other poultry constructions and it works equally well in colder weather. We can incorporate the Valeron system into both our timber-posted houses and our clear span, timber houses which can span up to 70ft wide.
“Once customers fully understand the properties of Valeron, their initial concerns about appearance and strength are overcome.”
The first day-old chicks arrived in early March from the Annyalla Chicks hatchery at Wrexham.
Even though the summer wasn’t the warmest on record, Mr Phelps says the building has been a real asset. He has also been able to make some comparisons with his two other broiler units, which are within a mile radius and house a further 150,000 birds.
“One of the issues with conventional poultry sheds in the summer is that the heat continues to build, making it really quite hot at about five to six o’clock.
“Valeron tends to even that out.
“It’s been difficult to contrast with the two other poultry sheds because we are rearing birds on different cycles, but in the summer the new shed was probably one to two degrees cooler.
“It acts rather like a thermostat, is quite reflective, which means I need less lighting, and it’s easy to wash and produces a good environment for the birds.
“I couldn’t claim that it improves feed conversion or boosts the European Production Efficiency Factor (EPEF) score, but the building is very good and the birds are finishing two days ahead of Ross targets.”
Another innovation is in the provision of heating for the plinth walls.
Mr Phelps has incorporated four rows of hot water piping in the concrete walling just above floor level to make the temperature even across the house and achieve an even spread of birds.
The exterior walls are lined with Van Dyke brown polysteel, with slate blue for the roofing and traditional timber cladding on the gable ends to blend into the surrounding countryside.
The heat is being generated by a biomass boiler – one component along with 400 photo-voltaic roof panels designed to make the site as near carbon neutral as possible.
The boiler provides the hot water for heat exchangers, with a tunnel ventilation system for keeping the environment cool in summer.
Allan Meldrum, director of Food Chain Innovation – which markets Valeron – said: “There is growing acceptance that a very durable radiant barrier is reducing heat stress issues by making the birds more comfortable and allowing them to attain much more of their genetic potential.
“We know that Valeron reflects up to 95% of radiant heat – 50% more than the cheaper alternatives – and the enhanced radiant barrier can save up to 30% on brooding cost,” he claims.
Initial heating-up times are also reduced to a few hours from the usual 24 hours.