BUILDING SERVICES – STUDENT’S NOTES
DBT/DCE
Introduction
- This module involves plumbing, electrical services and maintenance of building works. The
module unit is designed to equip the trainee with necessary knowledge, skills and attitudes
necessary in the design and installation of building services, and maintenance of buildings.
The skill gained will enable the graduate of this module to select tools and equipments and
to be competent in plumbing, electrical, mechanical services and maintenance of building
services.
- The trainee must have proper knowledge of general building construction methods course in
Module 1 and 2 to enable him/her handle plumbing, electrical and maintenance services, and
maintenance.
General Objectives
- By the end of the module unit, the trainee should be able to: -
a. Appreciate the design and installation of services, maintenance and demolition
b. Understand the concepts of measurement and estimation of building, plumbing and
mechanical services, maintenance and demolition.
c. Understand safety requirements in building services, maintenance and demolition
work
d. Apply the knowledge of building services, maintenance and demolition as required.
COURSE OUTLINE
1. Electrical Services
➢ Tools
➢ Instrument
➢ Tools storage
➢ Circuit diagram
➢ Installation
2. Safety and Regulations for Electrical Services
➢ Dangers
➢ Unsuitable clothing
, ➢ Attitude
➢ Abnormal usage of electricity
➢ Different Injuries
➢ Supply Regulations
➢ Factory Act
➢ IEE Regulations
➢ Fire Alarms
3. Ventilation
➢ Criteria
➢ Ventilation
➢ Ventilation opening in a Building
4. Plumbing Services
➢ Cold and Hot water supply
➢ Direct and Indirect systems
➢ Sanitary Appliances
➢ Drainage Appliances
➢ Drainage systems
➢ Storm water Drainage
➢ Piping
➢ Gas installation
➢ Fire protection
,TOPIC 1: ELECTRICAL NOTES
Specific objectives
- By the end of this sub-module unit, the trainee should be able to: -
➢ Identify hand and power tools
➢ Select proper hand and power tools and measuring instruments for a given task
➢ Use tools correctly
➢ Identify faulty and worn out tools
➢ Demonstrate proper methods of tools storage
➢ Design circuit diagrams
➢ Perform electrical installation in buildings
Definition of Conduit: A pipe for carrying electrical cables
Types of conduits
a) Metallic
(Class A – Light gauge, Class B – heavy gauge)
- Rigid Conduit
- Flexible Conduit
b) Non-metallic
(Class A – Light gauge, Class B – heavy gauge)
- Rigid Conduit.
- Flexible Conduit
Four types of metal conduit fitting
Types of Fittings
Conduit fittings can be listed as follows, based on the function they serve and how they are
installed:
a. Bends
- To save time, equipment and labor costs, you can tackle changes in the direction of a
conduit with pre-fabricated bends.
, - Commonly called ‘factory bends’ or ‘elbows’, they are available in a variety of lengths
and curvatures, and according to NEC requirements, you can bend certain tubings by hand,
using a mechanical bender or a hydraulic bender for larger ones.
- However, an installation may require a lot of bends, and bending conduits on location
might damage them or reduce the internal diameter.
- Even with the use of factory bends, the NEC does restrict the number of bends you can
have between pull boxes to a maximum of 360°, including offsets at the box or enclosure.
b. Couplers
- Conduit couplers are essential for almost any coupling system, for securely linking together
lengths of conduit and attaching site-fabricated bends.
- Even though PVC conduits with a belled side can be linked without couplings, they would
still be needed for sections where the conduit has been cut to size.
- Couplings are available in a variety of sizes and some of them, like rigid conduit couplings,
are threaded on the inside.
- However, when the conduit is passing through a wall or making some other transition,
consider using a conduit body instead.
- Even for the first sections of conduit entering or leaving the box or enclosure, use pull boxes
or bodies so the conductors can easily be retracted if the enclosure needs to be removed.
c. Drains
- In areas where the temperature varies significantly, or the conduit runs from a warm area to
a cooler one, moisture in the air starts condensing.
- To prevent drips and water-logging in the conduit runs, install drains at the lowest points of
each run that might be affected, or at locations where water might get trapped and
accumulate.
- For embedded and buried conduits, installing a run within the encased part may be difficult.
- You can create a low-point or a dip just before the conduit goes underground and install a
drain there.
d. Bushings and Locknuts
- Bushings create a smooth entry point to conduits without any sharp edges, protecting the
conductors from damage during wire pulls.
- They are also extremely important when the conduit system enters an enclosure or bus box.
- A bushing is installed on the inside of the box opening and threaded into the conduit end,
separating the conductors from the edges of both the opening and the conduit end.
- Locknuts are threaded on the inside, with teeth on one surface or both, which grip the
surface.
- They installed on both sides of the opening to ensure that both the conduit and bushing are
held firmly in place.
DBT/DCE
Introduction
- This module involves plumbing, electrical services and maintenance of building works. The
module unit is designed to equip the trainee with necessary knowledge, skills and attitudes
necessary in the design and installation of building services, and maintenance of buildings.
The skill gained will enable the graduate of this module to select tools and equipments and
to be competent in plumbing, electrical, mechanical services and maintenance of building
services.
- The trainee must have proper knowledge of general building construction methods course in
Module 1 and 2 to enable him/her handle plumbing, electrical and maintenance services, and
maintenance.
General Objectives
- By the end of the module unit, the trainee should be able to: -
a. Appreciate the design and installation of services, maintenance and demolition
b. Understand the concepts of measurement and estimation of building, plumbing and
mechanical services, maintenance and demolition.
c. Understand safety requirements in building services, maintenance and demolition
work
d. Apply the knowledge of building services, maintenance and demolition as required.
COURSE OUTLINE
1. Electrical Services
➢ Tools
➢ Instrument
➢ Tools storage
➢ Circuit diagram
➢ Installation
2. Safety and Regulations for Electrical Services
➢ Dangers
➢ Unsuitable clothing
, ➢ Attitude
➢ Abnormal usage of electricity
➢ Different Injuries
➢ Supply Regulations
➢ Factory Act
➢ IEE Regulations
➢ Fire Alarms
3. Ventilation
➢ Criteria
➢ Ventilation
➢ Ventilation opening in a Building
4. Plumbing Services
➢ Cold and Hot water supply
➢ Direct and Indirect systems
➢ Sanitary Appliances
➢ Drainage Appliances
➢ Drainage systems
➢ Storm water Drainage
➢ Piping
➢ Gas installation
➢ Fire protection
,TOPIC 1: ELECTRICAL NOTES
Specific objectives
- By the end of this sub-module unit, the trainee should be able to: -
➢ Identify hand and power tools
➢ Select proper hand and power tools and measuring instruments for a given task
➢ Use tools correctly
➢ Identify faulty and worn out tools
➢ Demonstrate proper methods of tools storage
➢ Design circuit diagrams
➢ Perform electrical installation in buildings
Definition of Conduit: A pipe for carrying electrical cables
Types of conduits
a) Metallic
(Class A – Light gauge, Class B – heavy gauge)
- Rigid Conduit
- Flexible Conduit
b) Non-metallic
(Class A – Light gauge, Class B – heavy gauge)
- Rigid Conduit.
- Flexible Conduit
Four types of metal conduit fitting
Types of Fittings
Conduit fittings can be listed as follows, based on the function they serve and how they are
installed:
a. Bends
- To save time, equipment and labor costs, you can tackle changes in the direction of a
conduit with pre-fabricated bends.
, - Commonly called ‘factory bends’ or ‘elbows’, they are available in a variety of lengths
and curvatures, and according to NEC requirements, you can bend certain tubings by hand,
using a mechanical bender or a hydraulic bender for larger ones.
- However, an installation may require a lot of bends, and bending conduits on location
might damage them or reduce the internal diameter.
- Even with the use of factory bends, the NEC does restrict the number of bends you can
have between pull boxes to a maximum of 360°, including offsets at the box or enclosure.
b. Couplers
- Conduit couplers are essential for almost any coupling system, for securely linking together
lengths of conduit and attaching site-fabricated bends.
- Even though PVC conduits with a belled side can be linked without couplings, they would
still be needed for sections where the conduit has been cut to size.
- Couplings are available in a variety of sizes and some of them, like rigid conduit couplings,
are threaded on the inside.
- However, when the conduit is passing through a wall or making some other transition,
consider using a conduit body instead.
- Even for the first sections of conduit entering or leaving the box or enclosure, use pull boxes
or bodies so the conductors can easily be retracted if the enclosure needs to be removed.
c. Drains
- In areas where the temperature varies significantly, or the conduit runs from a warm area to
a cooler one, moisture in the air starts condensing.
- To prevent drips and water-logging in the conduit runs, install drains at the lowest points of
each run that might be affected, or at locations where water might get trapped and
accumulate.
- For embedded and buried conduits, installing a run within the encased part may be difficult.
- You can create a low-point or a dip just before the conduit goes underground and install a
drain there.
d. Bushings and Locknuts
- Bushings create a smooth entry point to conduits without any sharp edges, protecting the
conductors from damage during wire pulls.
- They are also extremely important when the conduit system enters an enclosure or bus box.
- A bushing is installed on the inside of the box opening and threaded into the conduit end,
separating the conductors from the edges of both the opening and the conduit end.
- Locknuts are threaded on the inside, with teeth on one surface or both, which grip the
surface.
- They installed on both sides of the opening to ensure that both the conduit and bushing are
held firmly in place.
