Flood In Hospital

Royal Papworth Hospital Cambridge
  • CPL t/a Rainbow International provided an efficient and effective drying and sanitising solution, following a substantial leak at the ground floor of the hospital
  • Our service avoided the need for complete strip-out and reinstatement, saving the customer hundreds of thousands of pounds
  • No destructive monitoring techniques needed
  • Works completed ahead of schedule avoiding hefty penalties if project had been delayed
  • Disruption kept to a minimum

"I can always rely on CPL t/a Rainbow International to respond within 24 hours and, in the event of an emergency, to attend the site quickly and to also deliver on what was promised from the outset."

Francis Breen - Construction Director, Skanska


A substantial area of the ground floor of the hospital had a flood following a leak from a hot water pipe which had been running for about 7 hours before being noticed. Standing water was extracted by staff, but a few weeks later, surface mould and peeling paint work began appearing on the internal partitioning and behind access panels throughout the affected areas. They were concerned there may be mould spores trapped in the wet wall cavities and behind built in units and access panels. These issues had to be resolved before the project could be handed over to the client in two weeks’ time or would incur substantial penalties if the project overran.

We were contacted by Francis Breen from Skanska, the Construction Director on the project. He had a dilemma – he could either choose the very expensive option of total strip-out and reinstatement and incur penalties by exceeding the deadline or could choose the cheaper option of a drying and sanitising system to achieve their objectives within the given timescale.


Due of the size of the affected area and to prevent further destruction, we used a combination of non-invasive monitoring equipment on-site; thermal imaging and moisture readings to establish the full extent of the trapped moisture. In the areas identified as wet, we used a telescopic camera to inspect the wall void for mould infestations. At the time of our visit, all surface (none bonded) water had successfully dried out but pockets of bonded moisture were trapped in the voids between the partitions and behind units and access panels. Also surface mould was identified on the partitioning and in the wall cavity due to wall insulation and sound proofing in the wall cavities which was holding a lot of the moisture.

Thermal Imaging
Pressure plate drying


The current drying requirements in the property put it in ‘Stage Three’ bonded water drying process (trapped in materials with low porosity like concrete, hardwood, and void spaces). This required target drying, low humidity and increase in temperature of target material. We recommended Injection Drying as the lowest impact drying method as most of the water was trapped within partition voids which removed the need for extensive strip-out and reinstatement work.

Equipment Installed:

Desiccant dehumidifiers
Effective at extracting moisture from the air even at low temperatures, using a desiccant material. It works by blowing out dry air and absorbing the moisture from the area being dried.

High pressure air turbine
This machine takes the dry air produced by the desiccant dehumidifier and pumps it into the wall cavity under pressure, allowing it to push past insulation and other obstruction.

Self-draining refringent dehumidifier
This is only required to deal with the wet air exhausted from the desiccant dehumidifier as there is no access to vent these externally.

Monitoring and Estimated Drying Time:
We monitored the drying process every seven days and took action as necessary (e.g. repositioning equipment).   Our estimated drying time based of the level of moisture reading and the drying method applied was between 7 to 14 days, which we achieved with time to spare for reinstatement and hand over.

Mould Remediation:
The mould identified on the surface was not substantial and was treated with the application of an anti-microbial product, then wiped off the surface. The inaccessible areas were treated by pressure fogging through access holes drilled for drying. We were able to provide photographic evidence of the position of the mould within the void using our digital inspection camera with telescopic probe. To deal with any airborne spores released by the process, Air Managers were installed to kill all spores and remove odours.

Health and Safety:

The main risks were:

  1. Airborne mould spores: The installation of Air Manager will deal with the low level of airborne spores released.
  2. Manual handling: All our technicians are manual handling trained or supervised by a trained technician when moving equipment around the site.
  3. Slips, trips, and falls: Although trip hazards could be minimised but not completely removed, we had to agree measures like closing access to areas and signage to remove any remaining risk.
  4. Electrical safety of equipment: All equipment will be PAT tested within regulations. We also provided a detailed Risk Assessment and Method statement in line with CDM Regulations.

Completion Works Required:
We provided a scaled drawing of the site with the positioning of each hole drilled to assist the appointed contractor to reinstate. By installing the holes just above the skirting, they could be touched in, avoiding the need for painting the whole wall.  A builder’s clean of work areas was required on completion, however we limited the amount of clean up required by meticulously cleaning up as we went along.

Cost Savings:
There could have been an additional saving of about £10k if we were called within 48 hours of the flood – the likely drying time would have reduced by about 45% and there would have been no need for mould remediation.

Royal Papworth Case Study Tables

If you would like to find out more about our commercial flood and water damage drying and santisation services, get in touch with us on 0808 196 0363.