Whatever system is installed, it should be keeping the housing at no more than 20C to 40C above the external air temperature, said Thomas Burling, AHDB Pork environment team.

“A cooling system, such as a high pressure water vapouriser, can really help reduce the incoming air temperature so it is an option for producers to consider.

“Heat from the pigs and any manure or slurry, plus the solar gain on walls and roofs, also has to be extracted to limit elevation of internal temperatures.

“For this reason, air has to be moved sufficiently through the building and this is the most crucial time to ensure that everything is in the best condition possible and correctly sized.”

While moving air will provide comfort, the most important thing is to check that it’s actually moving at pig level, without giving a draught.

“We’re aware that some naturally ventilated buildings are proving difficult to manage and for this reason we’re looking at a number of options to improve air flow. However, it’s still a matter of getting the basics right first,” concluded Mr Burling.

The AHDB Pork environment team is happy to answer questions from producers who think their systems could be improved. They can also make personal visits to units to help managers better understand the ventilation.