Install cavity drainage membrane systems

The purpose of training delivered against this standard is to provide candidates with the practical skills and knowledge to be able to safely and effectively install cavity drainage membrane systems. It is aimed at people working in the Waterproofing sector.


Installation of Cavity Drainage Membrane Systems 


Minimum 2 days of 6 learning hours per day 


The purpose of training delivered against this standard is to provide candidates with the practical skills and knowledge to be able to safely and effectively install cavity drainage membrane systems. It is aimed at people working in the Waterproofing sector. 

The scope includes: 

  • designing a Type C System, the importance of BS 8102:2009 and other reference documents 
  • health and safety 
  • pre-installation preparation and checks 
  • detailing and excavating 
  • concrete slab/rafts 
  • perimeter drainage channels 
  • drainage Inspection access/maintenance ports 
  • sump installation 
  • combined systems 
  • installing the Type C membranes 
  • dealing with waste.  

Occupational relevance 

Training delivered against this standard would be relevant to the following occupational group(s):  

  • operative and craft 
  • supervision.


Candidates must have a basic knowledge of waterproofing terminology, tools and techniques. They must also have completed Installation of Drains Sumps and Pumping Ancillaries training. 

Instruction/ supervision 

As a minimum, course instructors must be able to demonstrate that, in relation to this standard, they have: 

  • a minimum of five years proven history spent working within the Structural Waterproofing Sector or able to provide evidence of recognised up skilling (e.g. Train the Trainer)   
  • proven competence in the design and delivery of training courses in structural waterproofing related construction topics and good presentational skills  
  • will hold the PCA Certificated Surveyor in Structural Waterproofing (CSSW) qualification and ideally Waterproofing Design Specialist (WDS) qualification.


Delivery may be in an on or off the job environment. 

All materials and equipment must be of a suitable quality and quantity for candidates to achieve learning outcomes and must comply with relevant legislation. 

The class size and candidate/instructor ratio must allow training to be delivered in a safe manner and enable candidates to achieve the learning outcomes: 

  • practical elements – 1: 4 (workshop)  
  • practical elements – 1: 2 (on site)  
  • classroom elements – 1: 8  

The following delivery methods may be used in the delivery of this standard: 

  • classroom or workshop 
  • a blend of classroom and e-learning 
  • onsite 

This standard is considered to contain 51% or more practical training. 

This standard is considered to be set at a basic/entry level.                                                      


For the successful completion of training, candidates must complete a multiple-choice question and answer assessment. 

Quality assurance 

Quality assurance against this standard will require initial approval of the training organisation and their content mapped to the standard.  

CITB will also conduct an approval intervention, either desk-based or centre visit, to ensure the training organisation can meet the requirements of the training standard.  

Approved training organisations (ATOs) will be required to present information on records of training and assessment upon request to CITB for desk-based analysis. They will also be visited annually by the CITB quality assurance team. 


There are no mandatory renewal or recommended refreshment requirements for this standard, however candidates are expected to continue to upskill with new products and techniques. 

Approval date 

May 2020 

Review cycle 

On request or within 3 years from approval date 

Learning outcomes

The candidate will be able to: 

Additional guidance to support learning outcome  

Understand the basic design principles of the Type C cavity drain membrane system 


design in accordance with the current standard BS 8120:2009 – “The Code Of Practice for the protection of below ground structures against water from the ground and other reference documents”. 

Adhere to health and safety measures 

understand the health and safety implications and precautions required when:  

  • installing the system  
  • using hammer drills  
  • using Stanley knives  
  • using tower scaffolds  
  • working in confined spaces. 

Carry out pre-installation preparation and checks 

including how to check for cables and hidden services  

Check the areas of installation and assess the need for further prep work 

ensure that the prep has been carried out. Identify the need for further prep work such as making good and sealing defects prior to installing the cavity membrane. Check soffits and falls required. 

Assessment of required detailing 


  • watertight structure pipe penetrations  
  • window reveals  
  • utilities and services 
  • detailing that will form part of the overall works. 

Determine concrete slab and raft requirements  


examine existing solid floors and assess suitability and preparation requirements for retention. 

Recognise authority from a Structural Engineer with regards to suitability of existing slab for use and removing perimeter material 

the candidate should understand how a Structural Engineer approved design reinforced concrete slab is constructed and the consequences of waterproofing existing slabs and creating rebates. 

Excavate the retained solid floor and form sump chamber(s)  

locate and design in the sump positions, consideration to issues when cutting through slabs and potential water ingress. 

Cast reinforced concrete slab 

to include: 

  • incorporating sump chamber(s)  
  • Slab to be cast level.

Install perimeter drainage channels  

to manufacturers specifications, including: 

  • connections within formed rebates in the existing floor slab 
  • to floor slab surface and approved insulation spacer. 

Design and fit jetting access/maintenance ports to the channel  

ports to be fitted as per manufacturers requirements and on a job by job basis 

Install sump correctly in chamber  

concrete chamber design and requirements for tanking to deal with potential water ingress and contaminates, as per manufacturers specifications. 

Combine waterproofing – two forms of waterproofing 

additional requirements include: 

  • reinforce joints and service entries  
  • smoothing coats and wall/floor detailing  
  • specialised waterproof product coatings to walls in accordance with manufacturer’s instructions. 

Flood test  

flood test floor and drainage to ensure test water runs freely to sump.  

Apply anti-lime coating to any new concrete walls and floor 


Calculate the amount of membrane product(s) that will be required  

in relation to the work area/specification in accordance with the manufacturer’s instructions. 

Fix Cavity Drainage Membrane  

in accordance with manufacturer’s instructions, including: 

  • to walls and vaulted surfaces using correct fixings and joint tapes 
  • using correct detailing at the perimeter for independent dry lining systems 
  • for receiving plaster direct or dot and dab fixed plasterboard 
  • to receive timber battens or frame fixed to membrane fixings from floor to ceiling to form dry lining ready to receive plasterboard. 

Install drainage channels and jetting ports 

complete connections between sump and drainage channel.  

Lay insulation former  


Lay appropriate Cavity Drainage Floor Membrane over prepared floor or approved insulation  

in accordance with manufacturer’s instructions, using correct joint tapes and detailing at the perimeter to receive various floor finishes. 

Identify the need for continuation of the waterproofing system in stepped and multi-level basements 


Mark final positions of rodding and jetting access points for maintenance and service of the drainage channels 


Connect outlet pipes to sump and to approved drainage or suitable land drainage 


Final test system and drainage for leakage and efficiency 


Deal with different waste materials 

to include:  

  • segregation  
  • bag up 
  • store safely for disposal 
  • recycling. 

Dispose of contaminated or hazardous waste materials 

in line with employer procedures. 

Complete all relevant paperwork 

to include:  

  • service and maintenance schedules  
  • floor plans.

Related standards 

  • Prepare surfaces for structural waterproofing 
  • Prepare structure joints and apply primary waterproofing 
  • Apply cementitious coatings, multi-coat renders and crystalisation active materials 
  • Installing and maintaining work area protection 
  • Install drains sumps and pumping ancillaries 
  • Hand held tools and equipment.