Department of Agricultural and Bio-System Engineering,
Makerere University
1 STUDY OBJECTIVES
Understand the importance, benefits and design characteristics
of farm structures
Be able to explain the three approaches used to determine the
economic feasibility of building investment
Be aware of the building plans and specifications
CHAPTER 1: PRINCIPLES OF FARM STRUCTURES
1.1 Importance of farm structures
Farm structures form an important part of any farming enterprise and
are required for the following:
The farmer and his employees require dwellings.
Farm animals, including poultry are housed part-time or full time
in buildings.
Buildings are required for certain activities such as shearing,
milking, sorting and grading of farm products.
Buildings are necessary for the storage of farming requirements
and implements, farm produce, feeds and food.
Buildings or rooms are necessary for a workshop and for office
from which the farm is managed.
Farm structures/buildings represent a production or storage cost.
Just as a return from feed or labour cost is expected, a benefit
from a building investment should also be anticipated.
1.2 Benefits that a building should provide:
(i) Facilities for an efficient operation.
(ii) An environment providing good health and sanitary conditions
(iii) Comfortable surroundings for both stock and workers.
(iv) Safe conditions for both stock and workers.
(v) Desirable conditions for production and storage.
Agriculture is not static. Changes and improvements in techniques
take place continuously. Farm buildings also have to be continuously
improved, altered and expanded to comply with the changing needs of
agriculture. The modern farmer therefore, must have a sound
knowledge of the planning, principles, layout, equipment and
constructional requirements of the different kinds of farm
structures/buildings. In addition, the farmer must be conversant with
practical buildings. Even if he/she has not intention of expanding
his/her farm buildings, the existing buildings require regular
09/U/289 1
,Department of Agricultural and Bio-System Engineering,
Makerere University
maintenance or improvements, which the farmer has to carry out or
supervise.
1.3 Planning, Design and Erection of Farm Buildings
Buildings can last for 30 years or more. Errors in the planning, design
or erection may therefore be a source of danger for many years.
Faculty buildings will also push up the operational costs of the
enterprise. The options of erecting buildings or altering existing ones,
and the nature of such buildings, rest primarily on the shoulders of the
farmer. Therefore, initially, the farmer must find out all he/she can in
connection with the buildings he/she intends to erect or alter.
Before embarking on the venture he should discuss it with his/her
family and his/her neighbours and if possible, with farmers who
specialise in his specific branch of farming. He must try especially to
obtain information on costs and returns in order to determine the
profitability of the project. The farmer should obtain answers to the
following:-
(i) How much will it cost?
(ii) Will funds for the project be readily available?
(iii) Will the quantity and or quality of the product be increased as
a result of the project?
(iv) Will it save labour?
(v) Will it make management easier?
(vi) And most important, what net increase in income will be likely
from the project?
When constructing a farm structure/building, the expense must be
justified. Effort should be made to estimate the cost and determine
the feasibility of the investment. Three approaches used to determine
the economic feasibility of building investment are:-
(i) Present practice theory:-
In which a building similar to others already existing in the
area is assumed to be justifiable.
(ii) Percentage of the gross income:-
If the cost of the proposed building is considered at a
reasonable amount to allow for annual building cost then the
investment is justified.
(iii) Residual after cost theory:
In which the cost of a building is provided for after all other
costs have been deducted from the gross income.
Explanation:
09/U/289 2
,Department of Agricultural and Bio-System Engineering,
Makerere University
The 1st of these methods is likely to emphasize what the average
farmer is doing or likely has done in the past. For instance an
alternative building or system may actually have resulted in over-
investment, thus making it a questionable example to follow.
Thus the 2nd and 3rd suggestions relate building cost allotment to
gross income. They imply that high income producing enterprises
can and perhaps should be housed in more expensive facilities.
1.4 Design characteristics of farm structures
A number of factors must be considered in planning a building to
obtain the greatest number of benefits at a reasonable cost. Some of
these design factors are:-
1. The functional requirements for the enterprise e.g. space,
temperature, light, physical protection, sanitation and safety.
2. The efficiency of the system including mechanization, centralized
operation, circular travel, and bulk handling of materials.
3. Structural design adequate to sustain the loads to which the
building will be subjected and one in which both the original cost
and maintenance costs are reasonable and one, which will provide
the desirable length of life.
4. The suitability of materials; including such characteristics as
durability, fire resistance, cost, upkeep, ease of cleaning, insulating
value and appearance.
5. Economy of construction. Costs are reduced by choosing module
(standard) dimensions, standardize, material and components and
profitable sub-assemblies.
6. Flexibility of design that will allow production methods for the
proposed enterprise to be altered or a completely new enterprise to
be established with minimum expense. Examples of planned
flexibility include such features as large doors, level floors, truss
construction and a large electrical service designed to allow the
addition of several circuits.
1.5 Building Plans and Specifications
A building usually starts with a drawing. The building plans are
drawings necessary as an aid in locating, arranging and fitting out
buildings and in estimating quantities of materials. Furthermore,
building plans are essential in order to prescribe to the builder what is
to be done and are always drawn on scale.
1.5.1 Scales
09/U/289 3
, Department of Agricultural and Bio-System Engineering,
Makerere University
The drawings are prepared according to scale. A numerical scale 1:100
means that 10mm on the drawing represents 1000mm or 1m on the
ground or structure.
1.5.2 Different types of drawings
In building construction, different kinds of drawing, each with a specific
purpose, are used. The following types are in general use:
1. Locality plans or sketches
These plans show environment, roads, farm boundaries and/or other
buildings. The purpose is to locate the building site
2. Site plans
These plans show the layout of the buildings in relation to each other
and to other objects. This type of drawing must be according to scale,
it is essential for the proper planning and layout of the farmstead, and
must indicate the positions of the existing and proposed:- roads,
buildings, fences, watering points, pipelines, septic tanks, electric
cables, telephone poles and trees. Site plans are important to;
to show exactly where the proposed buildings are to be erected in
relation to existing buildings;
to indicate where builders have to proceed carefully near
underground cables and pipes and/or
to indicate where they may connect to existing facilities.
- In addition, the following information is important:
contours,
true north
direction of prevailing winds
3. Setting-out drawings
These are the most important drawings because they show exactly
what is needed. They show what the proposed building(s) will look
like; how the various spaces within the building(s) are placed; the
general construction; location of principal elements; components and
assembly details. Very often they contain all the information that is
required to erect the building(s)
4. Component drawings
These are drawings of components or details of a building. They give
more details on the nature of certain components and how they must
be fitted into the whole and how they must be made
1.5.3 Specifications
09/U/289 4
Makerere University
1 STUDY OBJECTIVES
Understand the importance, benefits and design characteristics
of farm structures
Be able to explain the three approaches used to determine the
economic feasibility of building investment
Be aware of the building plans and specifications
CHAPTER 1: PRINCIPLES OF FARM STRUCTURES
1.1 Importance of farm structures
Farm structures form an important part of any farming enterprise and
are required for the following:
The farmer and his employees require dwellings.
Farm animals, including poultry are housed part-time or full time
in buildings.
Buildings are required for certain activities such as shearing,
milking, sorting and grading of farm products.
Buildings are necessary for the storage of farming requirements
and implements, farm produce, feeds and food.
Buildings or rooms are necessary for a workshop and for office
from which the farm is managed.
Farm structures/buildings represent a production or storage cost.
Just as a return from feed or labour cost is expected, a benefit
from a building investment should also be anticipated.
1.2 Benefits that a building should provide:
(i) Facilities for an efficient operation.
(ii) An environment providing good health and sanitary conditions
(iii) Comfortable surroundings for both stock and workers.
(iv) Safe conditions for both stock and workers.
(v) Desirable conditions for production and storage.
Agriculture is not static. Changes and improvements in techniques
take place continuously. Farm buildings also have to be continuously
improved, altered and expanded to comply with the changing needs of
agriculture. The modern farmer therefore, must have a sound
knowledge of the planning, principles, layout, equipment and
constructional requirements of the different kinds of farm
structures/buildings. In addition, the farmer must be conversant with
practical buildings. Even if he/she has not intention of expanding
his/her farm buildings, the existing buildings require regular
09/U/289 1
,Department of Agricultural and Bio-System Engineering,
Makerere University
maintenance or improvements, which the farmer has to carry out or
supervise.
1.3 Planning, Design and Erection of Farm Buildings
Buildings can last for 30 years or more. Errors in the planning, design
or erection may therefore be a source of danger for many years.
Faculty buildings will also push up the operational costs of the
enterprise. The options of erecting buildings or altering existing ones,
and the nature of such buildings, rest primarily on the shoulders of the
farmer. Therefore, initially, the farmer must find out all he/she can in
connection with the buildings he/she intends to erect or alter.
Before embarking on the venture he should discuss it with his/her
family and his/her neighbours and if possible, with farmers who
specialise in his specific branch of farming. He must try especially to
obtain information on costs and returns in order to determine the
profitability of the project. The farmer should obtain answers to the
following:-
(i) How much will it cost?
(ii) Will funds for the project be readily available?
(iii) Will the quantity and or quality of the product be increased as
a result of the project?
(iv) Will it save labour?
(v) Will it make management easier?
(vi) And most important, what net increase in income will be likely
from the project?
When constructing a farm structure/building, the expense must be
justified. Effort should be made to estimate the cost and determine
the feasibility of the investment. Three approaches used to determine
the economic feasibility of building investment are:-
(i) Present practice theory:-
In which a building similar to others already existing in the
area is assumed to be justifiable.
(ii) Percentage of the gross income:-
If the cost of the proposed building is considered at a
reasonable amount to allow for annual building cost then the
investment is justified.
(iii) Residual after cost theory:
In which the cost of a building is provided for after all other
costs have been deducted from the gross income.
Explanation:
09/U/289 2
,Department of Agricultural and Bio-System Engineering,
Makerere University
The 1st of these methods is likely to emphasize what the average
farmer is doing or likely has done in the past. For instance an
alternative building or system may actually have resulted in over-
investment, thus making it a questionable example to follow.
Thus the 2nd and 3rd suggestions relate building cost allotment to
gross income. They imply that high income producing enterprises
can and perhaps should be housed in more expensive facilities.
1.4 Design characteristics of farm structures
A number of factors must be considered in planning a building to
obtain the greatest number of benefits at a reasonable cost. Some of
these design factors are:-
1. The functional requirements for the enterprise e.g. space,
temperature, light, physical protection, sanitation and safety.
2. The efficiency of the system including mechanization, centralized
operation, circular travel, and bulk handling of materials.
3. Structural design adequate to sustain the loads to which the
building will be subjected and one in which both the original cost
and maintenance costs are reasonable and one, which will provide
the desirable length of life.
4. The suitability of materials; including such characteristics as
durability, fire resistance, cost, upkeep, ease of cleaning, insulating
value and appearance.
5. Economy of construction. Costs are reduced by choosing module
(standard) dimensions, standardize, material and components and
profitable sub-assemblies.
6. Flexibility of design that will allow production methods for the
proposed enterprise to be altered or a completely new enterprise to
be established with minimum expense. Examples of planned
flexibility include such features as large doors, level floors, truss
construction and a large electrical service designed to allow the
addition of several circuits.
1.5 Building Plans and Specifications
A building usually starts with a drawing. The building plans are
drawings necessary as an aid in locating, arranging and fitting out
buildings and in estimating quantities of materials. Furthermore,
building plans are essential in order to prescribe to the builder what is
to be done and are always drawn on scale.
1.5.1 Scales
09/U/289 3
, Department of Agricultural and Bio-System Engineering,
Makerere University
The drawings are prepared according to scale. A numerical scale 1:100
means that 10mm on the drawing represents 1000mm or 1m on the
ground or structure.
1.5.2 Different types of drawings
In building construction, different kinds of drawing, each with a specific
purpose, are used. The following types are in general use:
1. Locality plans or sketches
These plans show environment, roads, farm boundaries and/or other
buildings. The purpose is to locate the building site
2. Site plans
These plans show the layout of the buildings in relation to each other
and to other objects. This type of drawing must be according to scale,
it is essential for the proper planning and layout of the farmstead, and
must indicate the positions of the existing and proposed:- roads,
buildings, fences, watering points, pipelines, septic tanks, electric
cables, telephone poles and trees. Site plans are important to;
to show exactly where the proposed buildings are to be erected in
relation to existing buildings;
to indicate where builders have to proceed carefully near
underground cables and pipes and/or
to indicate where they may connect to existing facilities.
- In addition, the following information is important:
contours,
true north
direction of prevailing winds
3. Setting-out drawings
These are the most important drawings because they show exactly
what is needed. They show what the proposed building(s) will look
like; how the various spaces within the building(s) are placed; the
general construction; location of principal elements; components and
assembly details. Very often they contain all the information that is
required to erect the building(s)
4. Component drawings
These are drawings of components or details of a building. They give
more details on the nature of certain components and how they must
be fitted into the whole and how they must be made
1.5.3 Specifications
09/U/289 4
