A substantial area of the ground floor of the hospital in Cambridge was flooded following a hot water pipe leak 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 paintwork began appearing on the internal partitioning and behind access panels throughout the affected areas, thanks to the untreated flood and water damage. They were concerns 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, following the flood and water damage.
Due to the size of the area affected by flood damage 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 (non-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 soundproofing in the wall cavities which was holding a lot of moisture.
Francis Breen - Construction Director, Skanska
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 an increase in the temperature of the 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.
Effective at extracting moisture from the air even at low temperatures by 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.
We monitored the drying process following the flood and water damage every seven days and took action as necessary (e.g. repositioning equipment). Our estimated drying time based on 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 handover.
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 a telescopic probe. To deal with any airborne spores released by the process, Air Managers were installed to kill all spores and remove odours. The mould removal process was quick and smooth, creating a safe environment for the employees and patients of the hospital in Cambridge.
The main risks were:
We also provided a detailed Risk Assessment and Method statement in line with CDM Regulations.
There could have been an additional saving of around £10k if we were called within 48 hours of the flood and water damage – the likely drying time would have reduced by about 45% and there would have been no need for mould remediation. However, we were still able to reduce costs throughout the drying and mould remediation process by ensuring we only carried out the necessary work.
Here at CPL t/a Rainbow International, we are the local specialists in flood and water damage restoration in Cambridge. When disaster strikes, we are the leading provider in the area, offering professional and reliable services for our customers. At CPL, we do things differently, we’re with you every step of the way to guide you through the challenging process. We don’t just stop at sorting the water damage, we have experience liaising with insurance companies and loss adjusters, and fight tirelessly to limit costs and disruption for our clients. That’s why we are the leading choice when it comes to flood damage restoration and mould remediation in Cambridge.
Dry and mould remediation
Strip out and reinstatement cost
Total cost saving
Within 48 hours
Over 72 hours
Over 5 days