FARM BUILDINGS (2)

DESIGN CRITERIA FOR FARM BUILDING

So far.......

• Last week……Statutory frameworks as they affect farm buildings

• Today – look at the design of farm buildings and materials used in their construction

• Also some of the design considerations in designing buildings for accommodating livestock and produce

Learning Outcomes

• To be able to identify the main components within a farm building

• To be able to select appropriate materials in the design of farm buildings

• To be able to explain and incorporate the differing requirements in building design for a range of species of animal

Exercise….• For the farm building allocated to your group

provide the following:

1. Factors affecting the siting of the building2. A sketch identifying the constructional components of the building3. Suggest materials to be used in the construction4. The requirements in terms of internal fixtures and fittings5. Any other design criteria that you feel significant

Farm BuildingsThe Component Parts

Siting of Farm Buildings

• Consider:• Access to roads and other buildings• Aspect/exposure/climate• Availability of services• Topography• Soil conditions

Constraints....

• Electricity• Watercourses• Footpaths• Ancient and/or scheduled

monuments• Tree preservation orders• SSSI’s or similar environmental

designations

The Steel Portal Frame Building

Generally constructed around a number of steel Frames/columns set into concrete footings Areas between the frames in filled with generallyConcrete panels, timber or corrugated iron sheets

Constructional Information

Foundations

• Depth and width would depend upon:

• Building size

• Site conditions

• Bearing strength of the soil

• Building Span

• Portal width between columns

• Generally 9 m – 25 m but can be up to 40 m if in steel construction

• Shorter if timber construction (4 m -12 m)

Building Span

• Bay Length

• Refers to the areas between the steel frames

• Generally 4.5 m, 4.8 m or 6 m

• Many refer to a 15 foot bay (4.5 m)

The Bay

• Building Height

• Eaves Height

• Ridge Height

• Tend to be a maximum of 6 metres

Ridge Height Eaves

Height

• Roof

• Pitch

• Never usually flat roofs

• The pitch will depend on the ventilation requirements

• Generally between 14 -16 degrees

Pitch 14 – 16 degrees

Other considerations.......

• Water

• Fit pipes and troughs to protect from frost – tends to mean being between 750mm and 1350mm below ground level

• Consider the positioning of water troughs

• Dairy cows can drink up to 150 litres of water a day in summer

• Guide – allow for 10% of the herd to drink at any one time

Electricity• Some definitions:

• VOLTS – the pressure at which electricity is delivered

• 240 volts (single phase) is the norm

• 415 volts (three phase)

• AMPS – rate of flow of current through a cable

• WATTS – electrical power or overload, the rate at which an appliance will take power from the supply

• Delivered around the country in high voltage lines and cables and then reduced through transformers

Consider also….

• Lighting – natural and/or artificial

• Ventilation – probably the most important factor in designing a building so consider

• Location and local topography

• Proximity of other buildings

• Size and number of stock to be housed

• Physical dimensions of the proposed building

Natural Ventilation

• Wind Effect – effective at wind speeds above relatively low wind speeds

• Stack Effect – more important in stagnant weather conditions

Health and Safety in the Design of Buildings

• HSE Agriculture Information Sheet No. 35• Example - Dairy Bull Pens• Pen sited where they can see other cattle• 215 mm thick walls of reinforced concrete

topped with railings• Outer walls be at least 1.5 m high• All outer doors should be kept locked• Allow feed and watering from outside the pen• Include an exercise yard• Allow for an escape route

Materials..............• Concrete – what is it?

• A mixture of coarse and fine aggregates plus cement and water

• Water is needed to hydrate the lime and improve workability but too much water will weaken the concrete and give rise to voids in the concrete when it dries out

• 5% voids in the concrete can lead to up to 50% reduction in the crushing strength.

Concrete and Agriculture....• Resistance to acid attack and durability

• Use expansion joints when laying concrete

• Reinforcement – can be prone to corrosion, make sure it is covered with at least 40 mm of concrete

• Never lay concrete in cold weather

• Polythene membrane – prevents loss of water to the sub base and ensure the cement fully hydrates and also allow for thermal movement and reduce the possibility of cracking

• Curing – will take somewhere around 28 days to reach full strength after laying

Materials.........• Roof Materials• Fibre Cement – generally favourable

in high humidity buildings

Other Roofing Materials.......

• Box profile sheets – lighter but prone to corrosion

• Composite Sheets – generally two layers of steel cladding with insulation in between – usually crop buildings

Wall Materials

Drainage

• Clean Water System – roof water and other unpolluted water to a watercourse or soak away

• Slurry System – collects slurry and heavily polluted water and conveys it to a reception pit and storage tank

• Dirty Water System – collects lightly polluted water, like parlour washings and conveys it to settlement tanks

Dairy Cows• Consider:

• Water – cows in peak lactation need 150 litres of water per day – therefore allow enough water troughs to allow 10% of the herd to drink at the same time

• Passageways should be 2.5 m wide

• Feed passages be at least 3.6 m wide or 4.8 metres if the cubicles exit into the feed area

• Good access to the parlour

• Calving and isolation pens – guide 1 per 20 cows each of minimum 15 m2 area

Dairy Cows

• Cow weighing 600 kgs needs 9.0 m2 of space (bedded area and loafing area)

• Same cow needs 670mm of trough space

• Consider cubicle design – size, shape and weight of animals

• Have at least 1 cubicle per cow with ideally a 5% over capacity

Sheep

• Consider:

• Access roads

• Proximity to the shepherd

• Location of feed store

• Proximity to grazing and handling facilities

• Direction of prevailing wind

• Availability of essential services

Sheep

• Open Yards

• Partly Covered Yards

• Full enclosed buildings

• Remember sheep will be fully fleeced – so watch the ventilation

Space Requirement

• Pregnant Ewes weighing 61 -75 kgs needs 1.2 m2

• Same Ewe with lambs at foot needs 2.0 m2

• Sometimes provide a separate creep area for lambs up to 4 weeks old

Beef & Suckler Cows•Sufficient space

•Good feed access

•Generous ventilation

•Effective bedding

•Good water supply

•Buildings be flexible to Accommodate differing groups

•Group sizes –•Heifers & Steers – 40•Bulls – 20

•Handling Facilities

Space Allowances

• Store Animal 7 months of age needs 3.0 m2

• Store Animal 16 months of age needs 4.2 m 2

• Store Animal 26 months of age needs 5.4 m 2

• Single Suckler cow plus Calf needs around 6.0 m2

Buildings for Storage

Storing Grain

• Grain contains starch and will germinate in suitable conditions

• It gives off heat and moisture during storage which can lead to sprouting of grain in store

• Susceptible to insects and diseases and controlling temperature moisture content will control this

Design Criteria

• Frame to take the thrust of the grain

• Floor – reinforced concrete 150 mm above ground floor level with damp proof membrane joined to the walls

• Also timber or concrete drive over slotted floors providing under floor ducts

• Walls – reinforced mass concrete or prefabricated steel or timber panels fixed to upright stanchions

• Essential building is bird and vermin proof

Design Criteria

• Ventilation – allow natural ventilation for dust

• Adapt gable wall with wall louvers with wire mesh either fixed or mechanically operated

• Mechanical air intake, maybe extractor fans may be needed

The Harper Adams University College – New Dairy Unit

Why was a new dairy unit needed?

• Existing facilities no longer fit for purpose as a teaching and learning facility

• Increasingly uneconomic to run and operate

• Unlikely to satisfy the environmental and welfare standards beyond the short term

Design Features

• 2 spacious, light and airy cow housing buildings aiming to offer optimum conditions for dairy cow health and maximum ventilation

• Logical layout of building to ease management of the herd

• Space between buildings means that there are distinct clean and dirty areas

Design Features

• 1 area solely cubicles and an area of mixed cubicles and straw yards

• Spacious cubicle accommodation for the large modern dairy cow

• Cubicles lined with latex mattresses with a rubber top covered with a lime material to reduce build up of bacteria

Design Features

• Slurry scrapped automatically every 4-5 hours into channels to an underground slurry pit

• Passageways can be washed down using water from tipping water troughs which then automatically refill

• Water from the parlour is channelled back into a holding tank and recycled for flushing through the collecting yard after milking

Design Features

• Slurry not diluted by rain water

• Dairy unit has own borehole with treated water only used for cleaning the milk plant

• Heat exchanger transfers heat from the milk to preheat the hot water system