What it involves

A patch repair is a short length liner, used to repair isolated defects within longer pipe lengths.

The McAllister Group offer patch repairs in using the traditional ambient cured method or the faster UV Cured method which has a curing time of around 10 minutes.

Our Service 

  • A short sleeve wetted-out on site, typically using silicate resin
  • Full structural repair bonding to existing pipe even in wet conditions
  • Highly resistant to chemicals and abrasion
  • Hard surface finish gives improved flow characteristics
  • Tapered edges give a smooth flow transition

Our Process

  • A short (0.5m-1m long) sleeve is wetted-out on site. Packers up to 3m long are available for long length CIPRs
  • The sleeve is wrapped around an inflatable packer
  • The packer is lowered into the relevant pipe length and winched into position, where appropriate using CCTV to aid location
  • The packer is inflated by compressed air to push the repair against the host pipe whilst the repair cures, usually at ambient temperature – the packer allows ongoing flow through its centre
  • Once the cure has completed, the packer is deflated and removed
  • A final CCTV survey is carried out to assess the repair quality and record the new condition of the pipe length


  • Area for onsite wet-out
  • Safe access to appropriate chamber
  • Relatively straight access to damaged area e.g. no swan necks etc
  • Access for pre and post CCTV survey
  • 2-4 hours site access
  • 100mm – 1200mm diameter

When to use CIPP patch repairs and their benefits

  • Localised patch drain repairs smooth over displaced joints, seal cracks and holes reducing the resistance caused by such defects. The net effect of the patch is to increase the flow of solids and liquids which in turn helps to prevent future blockages in a problem drain
  • The patch repair also prevents further root ingress or water ingress by sealing the pipe internally and restoring the structural stability of the pipe. This method is successfully used worldwide to seal pipes with water infiltration or pipes that have failed air tests which can prevent sewer adoption
  • If there are multiple defects in a pipe, a judgement needs to be made as to whether multiple patches or a full length liner is appropriate. The decision is normally made by balancing the relevant costs and the probability of further degradation of areas which would not be repaired by patching.

Why choose the McAllister Group for CIPP Patch Repairs

People – Our staff working with the application are highly experienced and manufacturer trained and are focused on delivering a quality and professional solution

Partners – In most cases, we make use of the EPROS system which has passed the WRC short-term hydrostatic testing procedures and is used extensively throughout the world. We enjoy a collaborative working relationship with EPROS which affords our customers better lead times, better service and technical support provision

Experience – the McAllister Group has installed thousands of CIPP patch repairs across England within the last 2 years but we have made use of these applications for over 30 years