Good, efficient housing makes management easier and helps the farmer to successfully rear 85 % or more of all the live born piglets to market weight in the shortest possible time. Pigs at different stages of growth need different environments (temperatures). If they are to produce and grow to their maximum potential piglets need special protection against very low temperatures. Growing and reproducing pigs must be protected against high temperatures. The houses must therefore be built in such a way that the pigs are protected against extreme temperatures and other bad weather conditions such as cold winds and continuous rain.

The boar pen

  • Boars are kept separately in their own pen. One boar is
    kept for every 15 to 20 sows. On a pig farm with only 20 sows it is advisable to keep at least two boars, namely a young not too heavy boar for young sows and gilts, and an older boar for older, heavier sows. You will therefore need two pens.
  • Sows are brought to the boar to be served in the boar pen. This pen should be 9 to 10 m2, with the short side at least 2 m wide so that the boar can easily turn around in it.
  • The floor should be made of cement and must not be slippery. It should slope towards the sides and to the front so that urine and waste water can drain into a shallow manure channel at the front of the pen.
  • The walls must be of solid concrete or cement plastered brick. Gates can be made of round iron pipes, with a 20 mm diameter, spaced vertically not further apart than 75 mm. The height of the gate and also the walls should be 1 400 mm.
  • An under-roof sleep area, about a third of the size of the pen, must be covered in bedding. Straw, grass or sawdust can be used for this purpose.

  • A feed trough is placed in the sleeping area in such a way that it does not get filled with bedding. The trough for each boar should be 450 to 600 mm long, 150 to 200 mm high and 500 mm wide.

  • Cool, clean water must be available at all times on the side where the gate is. The pig will also dung in this area. A small water trough with a ball valve to control the level of the water or preferably a pig-drinking nipple can be used. The nipple must be placed at a 90° angle with the vertical and between 550 and 650 mm from the floor.

  • Make sure that the boar pen is well ventilated and draught free. It is important that the temperature does not rise higher than 22 °C for long periods. If the temperature rises above 32 °C the boar may become infertile for up to six weeks. On very hot days boars can be kept cool by sprinkling them with water.

  • Gilts and dry sows

    • Gilts should be brought to the boar for the first time when they are 7,5 to eight months old.
    • Dry sows come onto heat three to seven days after weaning when they have to be served by a boar again. Therefore, keep gilts and dry sows to be served in pens next to or near the boar so that they can be checked for heat daily until they are served.
    • Do not keep more than five gilts or sows in one pen.
    • Gilts and sows should not be kept in the same pen.
    • An area of about 5 m2 per pig is required. Therefore, to house five pigs a pen with an area of approximately 25 m2 is required.
    • The construction and specifications (apart from the size) of the sow/gilt pen are the same as that of the boar pen.
    • Individual feeding is, however, important to ensure that each pig receives the correct quantity of feed every time. Enough trough space with partitions that allow the pigs to eat individually is therefore necessary.
    • Nineteen days after the pigs have been served by a boar they are again brought into contact with a boar for five to seven consecutive days to make sure that they are pregnant. If the boar does not serve them again, it can be concluded that they are pregnant and they can then be placed in the pregnant sow house.
  • Pregnant sows

    Pregnancy lasts 114 to 116 days. Sows are put in the pregnant sow pen about 24 days after service and are only moved to the farrowing pen seven days before they give birth. They stay in these pens for about 85 days. The pens can be similar to dry sow pens. Provided the sows are about the same size, up to five pregnant sows can be kept in one pen. To make sure that each pig receives the correct quantity of feed, provision should again be made for individual feeding. The construction of this pen is also similar to that described for boar pens. At least two and preferably three pens (to house a maximum of five pregnant sows each) are needed.

    Farrowing pens

    The farrowing pen is the most important pen on the farm. It has to be designed in such a way that the right temperature is provided for the sow and her piglets during the first seven to 10 days after birth, while trampling and overlying is prevented as far as possible.


    • It is advisable to build a farrowing house (large room) containing five or six farrowing pens. A five-pen house should be 13,25 m long, and a six-pen house 15,5 m. The width in both cases should be 4 m. Each pen will be 2 x 2,25 m with a 1 m wide feed passage on the northern side of the pens and a 1 m wide dung passage on the southern side. The entrance must be on the short side of the building with a 1 m space between the outside wall and the first pen. The space is linked to the feed and dung passages. The figure on the following page illustrates the layout of a typical farrowing crate.

    A sow in a farrowing crate
    • Each pen must have a farrowing crate (see figure on p 42) where the sow is kept from one week before the piglets are born until they are weaned when they are 28 or 35 days old. The crate is placed in the pen allowing a space of about 1 m on the one side and 0,5 m on the other side. The feed trough (500 mm long and 200 mm high) for feed and water is on the feed passage side of the pen. If water is laid on in the farrowing house a water nipple can be placed above the feeding trough. The entrance gate is on the side of the dung passage.
    • A creep area must be provided for the piglets. A steel or wooden box, 600 x 600 mm which is large enough for the litter to creep into, can be placed next to the feed trough and the feed passage wall. The creep is important because it helps to reduce deaths as a result of crushing. It also provides a draught-free area where the piglets heat one another. In this way the creep area provides the required temperature of 27 to 32 °C for piglets during the first 10 days of life.

    • The farrowing house must have windows on both sides (on the long wall sides) to ventilate and cool the house. The temperature where the sow is kept (in the farrowing crate) should preferably not be higher than about 21 °C.

    Side view
    Top view
    Section AA (seen from above)

    Plan for a typical farrowing crate
    Note: Use 16 mm and 20 mm diameter steel pipes and rods for farrowing crate construction.

    Weaner and finishing house (growing pigs)

    Piglets are weaned when they are only 28 days old. They must therefore be looked after with care for at least another four to six weeks until they are 10 weeks old. They must be kept in pens at a temperature of 17 to 25 °C and draughts and wet conditions should be prevented.

    It is advisable to keep the growing and finishing pigs in pens similar to those used for weaners.

    A weaner/finisher house with 20 pens must therefore be built. Each pen
    must be large enough to house a litter of 10 to 12 pigs, kept in the pen from the age of four weeks until they are sold at a live weight of 90 to 110 kg. Two rows of 10 pens are built in the house. The building will be 40 m long and 9 m wide. The individual pens, should be 12 m2 or 4 x 3 m with 1 m high concrete walls, and two 1 m wide dung passages along the north and south walls of the building with a feeding passage, 1 m wide in the middle between the two rows of pens. The entrance to the building is again to the short side of the building with a 1 m space between the outside wall and the first pen linked to the feed and dung passages. The entrance gates to the pens are on the side of the feed passage. Water troughs or drinking nipples are fixed to the pen walls facing towards the dung passages.

    The pigs will lie down and sleep along the inside wall of the pen where the feed trough is placed. Growing pigs must have access to feed at all times. It is therefore ideal to use self-feeders. An effective self-feeder can be set in such a way that feed wastage is restricted to a minimum (feed is expensive and must not be wasted by the pigs). A long concrete trough built next to the feed passage wall, can also be used, but usually causes the pigs to waste feed and is therefore not recommended.

    If you want to keep piglets healthy and alive, keep them warm, and if you want the sows to have enough milk for the piglets, keep them cool


    Handling of manure

    The solid manure which contains some bedding must be stacked outside in windrows. It is important to stack the manure in such a way that water will be allowed to drain from the manure as quickly as possible. Stacked manure has an unpleasant smell and becomes a breeding place for flies if left in a windrow for a long period. It is therefore, essential to air the manure in the windrow by turning it regularly. The oxygen in the air keeps the anaerobic bacteria in the manure alive and in this way helps to turn the manure into valuable compost. On a 20-sow pig farm up to 300 tons of composted manure can be produced every year. The compost can be used as fertiliser on cultivated lands or can be sold as compost.

    An income equal to the sale of 20 baconers is possible if good-quality compost is produced

    Make compost by adding soil, grass cuttings, leaves, etc. It can be used as fertiliser on cultivated lands or can be sold for an extra income

    Diagrammes of required buildings

    Build three pig houses:

    • A building for boars, gilts, dry and pregnant sows
    • A farrowing house
    • A building to keep growing pigs in from the time they are weaned until they are sold to be slaughtered.

    The diagrams show the number and size of each pen required on a farm where a maximum of 20 breeding sows are kept.

    Building plans and equipment

    Detailed building plans and information on the equipment required on a pig farm can be obtained from the ARC Institute for Agricultural Engineering, Private Bag X519, Silverton 0127, tel: (012) 842 4000. The Institute can also advise you on the outlay of the unit. The figureon the following page.

    Outdoor housing of pigs

    • Pigs can also be kept outside in camps where shade structures provide the necessary protection against wind, rain and excessive heat or cold.
    • The capital required to start outdoor pig farming is therefore 20 to 30 % less than the amount of money required for an indoor unit.
    • There are both advantages and disadvantages which must be taken into consideration before deciding to build an outdoor piggery instead of an indoor unit.


    • Strong and healthy weaner pigs can be produced on a properly run outdoor pig unit.
    • Labour costs should be less.
    • There will be less problems with the disposal of manure.

    • Capital costs will be appreciably less.

    • Disadvantages

    • Lower productivity because pigs grow slower and most probably less pigs will be produced. Profit margins could therefore be smaller.

    • Handling of individual pigs will be more difficult.

    • Sows that are not pregnant or that are infertile will be difficult to identify.

    • Pigs can only be kept out of doors on light soils that are well drained.

    • Strong fencing is required to ensure that pigs are kept inside.

    • Mud during the rainy season can be a problem, hindering access to the camp.

    • Feed is wasted as a result of birds and predators eating the pig feed.

    • Loss of piglets killed by predators.

    Sketch with dimensions of a building for boars, gilts, dry sows and pregnant sows

    Sketch with dimensions of a building for growing pigs from 
    weaning to slaughter (minimum 16 and maximum 20 needed 
    for a farm with 20 breeding sows)

    Sketch with dimensions of a building 
    for sows with piglets (farrowing house)
    Outside wall and roof dimensions of the buildings (length of the building should be east/west)


    Requirements for outdoor pig farming

    A suitable climate, the correct type of ground surface and well-trained, motivated labourers are essential.


    • Temperatures must be within the thermic neutral zone for pigs—preferably not below 15 °C and not higher than 30 °C.
    • If temperatures are lower or higher additional heating or cooling is necessary.
    • Enclosed straw-covered areas can supply additional heat.
    • Cooling can be supplied by shade structures or mud puddles.


    Do not farm out of doors in high-rainfall areas—more than 500 to 800 mm per year.

    Soil type

    The soil must be light and well drained. Camps, pens and paths that are always wet can ruin the unit.

    Level of the ground

    Fairly level ground that does not slope too much is needed. Too much of a slope will hamper access to the unit. Earth and straw will also wash away if the slope is too big.


    • Provide good water supply to all the camps and pens.

    • The camps must be accessible to vehicles for loading and offloading of pigs.

    Example of a camp system for 25 producing sows

    (ILI Extensive Pig Housing, ARC Institute for Agricultural Engineering, Silverton)

    The sows are divided into groups of five and remain together in their groups in the camps.

    The table shows the number of camps, pigs and camp sizes for a 25-sow unit.


    Number of camps, pigs and camp sizes for a 25-sow unit

    Type of camp 

    Number of camps

    Number of pigs per camp 

    Proposed camp size (m2)



    5 sows x 2 boars 

    3 000

    Dry sow


    5 sows x 1 boar 

    3 000



     5 sows x litter 

    3 000


    5 sows x litter 

    2 000




    2 500




    3 000


    At least 4,55 ha of land is therefore needed for erecting the camps. Land is also required for a feed and equipment store, houses for the farmer and workers as well as roads.


    Proposed layout for an extensive camp system with 25 producing sows

    Chamber type farrowing structure in camp

    Triangular farrowing structure in camp

    Steel frame gate for use in camps