How to improve ventilation in existing buildings as your stock moves indoors for the Winter
Poor ventilation in existing facilities is usually because inlets and/or outlets are absent or too small. Inlets and outlet areas should be at least brought up to the sizes outlined in the DAFM specification S101. Inlets typically used in Ireland are vented sheeting and spaced boarding. These are effective as long as there is at least a 1.5 m depth along under each eave. Fabric mesh materials are also effective and have the added advantage of letting in more light. Another method of improving airflow entry is to angle out the side cladding, at the bottom. Moving out the side cladding to leave a clear opening between the side wall of the shed and the side cladding, just below the top of the side wall, will provide a good inlet. Air is deflected upwards from the side wall as it enters. This can be done easily enough with box section steel. The box section will make it secure and will allow the gap width to be maximized. Where sheds have a wall built right up, the easiest solution is to knock off a few lines of blocks to provide a continuous opening. Monitor how it works to see if any more needs to be done. Small, inexpensive, changes are the best approach, followed by careful observation for improvements during the following housing period.
Perhaps the ridge outlet area can be increased by, for example, raising the ridge cap. Spaced sheeting is really not practical unless all the sheeting is being replaced. With round roofed sheds raising sheets (2 per bay) along the top by about 225 mm is effective.
Raising sheets is a practical method to turn the roof into a “breathing roof”.
One or two lines of sheeting per bay can be raised above the plane of the roof by about 100 mm to 150 mm with an overlap of about 100 mm to 150 mm, at each side, to prevent in-blown rain. The raised sheets run up along the slope of the roof (which is usually across the width of the shed) and possibly up and over a round roofed shed, as well, if one is present. The size of the outlet can be calculated by multiplying the total length of all the openings by the raised height and comparing them to the guidelines. Some new sheets will have to be used also. These are wider (960 mm or 990 mm) and may be used over the opening as a single line of sheets (most common way), or possibly could be cut into three strips to be used with existing sheets. The new sheets are available in the 750 mm width also. There are different ways to fix the raised sheets. The simplest way would seem to fix box irons (weld cleats on them and bolt to the purlins) above the purlins at the right height and secure the sheets to the box iron with tech screws. The box iron should be long enough to support the overhang of the sheeting at either side.
Light is also very important in animal housing, mainly for the animals but also for the person looking after and observing them. Any improvements to natural light that can be made in conjunction with making improvements in ventilation should be availed of.
Checklist:
Water An adequate supply of clean water for housed livestock is essential.
• To avoid water freezing. locate pipes underground.
• Do not locate troughs on external walls.
• Use heavy gauge piping and minimise the number of joints.
• Consider feeding each trough individually with un-jointed pipe runs.
• 20 mm bore piping will be provide adequate flow rates for most situations.
• Proprietary anti-fouling troughs will minimise requirements for cleaning.
This information is publically available as part of the Teagasc Beef Manual available on Teagasc.ie
