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Above Ground Building Drainage


Upcoming Courses 
Key Areas
Course Content
Learning Outcomes
Who Should Attend
Course Timings
Course Fees
In-House Training

A full overview and agenda, need to know information, and booking instructions can be found on the individual upcoming course pages. Click on a course below to view.

Upcoming Courses 

28th November 2019 | London - Find out more


Key Areas 

This course will give a well-rounded introduction to above ground drainage principles. Attendees will be able to identify the different types of above ground systems, understand how they interact and calculate discharge capacities using BS EN 12056.

The course will also consider common problems including trap seal loss, offsets in ceiling voids and ancillary equipment including air admittance values, waterless traps and level access showers. It will consider when they need to be used and how to incorporate them into a design.

Attendees will also:

  • Calculate rainwater discharge for flat roofs & gutters and how to incorporate overflows  
  • Consider how fire safety and acoustic issues affecting multi-occupancy buildings and maintenance access within a design  

Course Content 

Session 1: Foul Drainage Principles

  • Introduction- Case study (Amoy Gardens HK)
  • Types of drainage systems
  • Determining discharge rates in foul systems
  • Frequency and realistic discharges
  • Worked example and one to solve   

Session 2: A fresh look at Ventilation in Foul Drainage

  • The traditional view of air movement in drainage and trap seal loss
  • How air really moves in soil stacks- the importance of transients
  • Vent header on complex systems
  • Discharge stack connections/ use of stub stacks
  • Waterless traps and air admittance valves

Session 3: Rain Water Drainage

  • Calculating discharge rates for rain water systems
  • Flat roof considerations including overflows
  • Gutter design and considerations
  • Worked example and one to solve
  • SUDS and attenuation requirements/ fast or slow water?
  • Green or Blue roofs and rainwater harvesting options

Session 4: Special applications, material types, testing and maintenance 

  • Material selection including noise and fire considerations
  • Demise issues in multi-occupancy buildings
  • Level access showers and adaptable bathrooms
  • Maintenance access
  • Testing systems
  • References, bibliography and recommended reading

Learning Outcomes 

  • Explain key design principles for waste water systems
  • Describe typical system layouts
  • State 3 of the 9 types of trap seal loss
  • Describe the movement of air within a system and the importance of ventilation
  • State when and how to use stub stacks
  • ​​Explain key design principles for rainwater systems

Who Should Attend 

This course is designed for people with limited knowledge of above ground drainage systems who require a general overview of the whole subject covering the features that may be encountered in a typical building drainage scheme.

Course Timings 

Registration will be at 09.30
Start Time: 10.00
Latest Finish: 5.00

Course Fees 

  • Members Rate: £280 + VAT
  • Standard Rate: £310 + VAT

In-house training at your site

Training multiple staff at once provides the opportunity for your organisation to have a training package crafted to your specific needs. In-house training can help your organisation overcome challenges and fill the skills gaps in your workforce. Courses run on a minimum number of six staff*.

For an In-house quote please email the following information to

  1. Name of course
  2. Approximate number of staff
  3. Your site address  

*Minimum numbers for In-house courses outside of the UK may vary

To contact the CIBSE Training Team with a query please

Email: or call: +44 (0)20 8772 3660