5th October 2023

How to weatherproof pig housing to maintain air quality and maximise performance

Although nutrition and genetics play a major role in producing healthy and profitable pigs, it’s crucial to not overlook the impact of the environment on productivity. A healthy environment can lead to increases in feed conversion rates, average daily live weight gain (DLWG) and welfare standards.

In addition, providing a healthier environment will lead to decreases in the severity and levels of respiratory illnesses[1].

Why is air quality important for pigs?

Maintaining good air quality and ventilation in pig units can be a challenge due to a number of factors. Air quality is measured by the levels of pollution in the air which could be harmful to animal health or the environment.

The most common air quality contaminants in pig units are carbon dioxide, ammonia and dust, however others can be present. High levels of carbon dioxide have a negative impact on production, reducing the growth rate and increasing the prevalence of respiratory disorders.

The level of CO2 should be kept below 0.3% of the air at pig height, which means that the ventilation rate should be maintained at a high enough rate to avoid going over this threshold.

Maintaining optimal air quality is essential for productivity but also for minimising the risk of illness and mortality. A well-maintained barn with either natural or mechanical ventilation solutions can go a long way to solving any issues.

Good ventilation is also essential for maintaining the correct temperature in pig housing as well as removing air quality contaminants, as it removes the stale warm air and replaces it with fresh, cooler air.

Pigs should be kept in the thermoneutral zone that is appropriate for their weight group, with a humidity between 60-80%.


A graph to show the ideal temperature of different weights of pigs

Weight of pig (kg)[2]

Ideal temperature (°c)








Tips for weatherproofing pig housing

By weatherproofing sheds properly pigs are protected from harsh weather conditions, such as rain, wind, extreme temperatures and high humidity. A well weatherproofed shed will prevent water leaks and reduce drafts, while maintaining a consistent temperature and ventilation rate inside the housing.


With extremes in temperature becoming more common, insulating pig sheds is fundamental to keep pigs at an optimum temperate during cold weather and heatwaves.

Good insulation will help to mitigate temperature fluctuations in the unit, which can prevent health issues.

Installing high quality insulation in the roof and walls can also help to reduce the amount of money spent on heating and cooling the house, reducing energy costs.

Good ventilation without a draughts

A well-designed ventilation system is essential for maintaining excellent air quality within pig housing. Mechanical ventilation systems, like fans, can be installed to ensure a constant flow of fresh air while removing stale air.  However, it is often much more cost effective to use natural ventilation where possible.

Effective ventilation can be achieved when there is wind speed over 1m/s and this occurs about 95 per cent of the time in the UK[3].

Additionally, all doors and windows should be well fitted and sealed to prevent draughts.


Galebreaker offer a series of door systems that can be used to take advantage of the great British weather, by allowing for variable ventilation while offering weather protection.

An automated system, such as the VVS Side Curtain System, can reduce labour costs while providing an effective weather proofing solution with high good ventilation. It is made of mesh material to increase ventilation and utilises an automatic control system to open and close fabric curtains, depending on temperature, wind speed, wind direction and rain sensors.

The Agridoor Electric offers the same fantastic weather protection and ventilation, but can be opened and closed at the push of a button.

State of the art pig unit at Plumpton College, Sussex    side curtain system


Regular maintenance

Weatherproofing measures are only effective if they are well-maintained. Regularly inspect the insulation, doors, windows and ventilation systems to identify any potential issues.  Promptly address any leaks or damages to ensure the weatherproofing remains effective and reliable.


[1] www.sciencedirect.com/science/article/abs/pii/S0167587720308345#preview-section-abstract

[2] https://www.fwi.co.uk/livestock/pigs/how-to-get-pig-housing-conditions-right-for-best-performance

[3] https://ahdb.org.uk/knowledge-library/natural-ventilation-in-pig-buildings