John Lewis Distribution Hub with moisture mapping

Find out why Ridge and Partners used moisture mapping surveys to help them save time and money on a multi-section roof.
John Lewis Distribution Hub image

Using BMI’s moisture mapping service to reduce costs


The roof of the John Lewis Distribution Hub in Killingworth, Newcastle Upon Tyne was nearing the end of its service life. To kick start the regeneration project the roof needed, consultants Ridge and Partners enlisted the service of BMI’s technical experts to support the specification using moisture mapping surveys. 

The Distribution Hub had four main sections across two different elevations. For this phase of the project, the focus was on the two largest of these sections. 

  • Location: Killingworth, Newcastle Upon Tyne

  • Client: John Lewis

  • Consultants: Ridge and Partners

  • BMI Icopal Services: Moisture Mapping

The Challenge

The Challenge

As the roof was nearing the end of its service life, the building owner had planned in some preventative maintenance. This was to understand the current condition of the roof and find a cost-effective solution for any repair work needed. 

Ridge and Partners were appointed to complete the scoping and specification of remedial work. Before any work could commence they needed to understand the current condition of the roof. 

That’s why they chose to work with BMI Icopal.

The Challenge - Avoiding unnecessary costs, while making essential repairs

The solution

The solution

Ridge and Partners wanted to use BMI Icopal’s moisture mapping service to understand the current condition of the two roof sections and see what repair work was needed. 

The moisture mapping surveys discovered that the coverings and insulation on one of the sections were damaged with water ingress, meaning that overlaying would go against best practice and reduce the service life of any new roofing system. 

However, except for the one valley gutter, the main roof coverings and insulation on the other roof section were found to be in good condition. This meant that Ridge and Partners could focus on the areas of the roof that needed the most work and allow the building owner to save money on areas that didn’t need repairs. 

The solution - Uncovering hidden issues in the roof through moisture mapping

The impact

The impact

The moisture mapping service found that more than 40% of one of the roof sections was damaged. This meant that the 510m2 roof needed to be stripped and then replaced. 

On the other section, the gutter beds were removed and replaced and a new Cut to Falls tapered insulation scheme was installed to improve cross falls. As the moisture mapping service found that this roof section only needed partial repair work, the building owner saw a 25% cost saving for this project. 

From an environmental perspective, the moisture mapping service also helped reduce unnecessary waste from going into landfill. 

The impact - 25% cost savings made from avoiding unnecessary repair work

In focus: Moisture Mapping

Using specialised equipment, BMI Icopal’s Moisture Mapping service helps identify the moisture levels in various parts of a roof. This can help contractors and building owners save time and money as they understand exactly what needs to be repaired or replaced. 

It is twice as fast as Nuclear moisture mapping survey methods and able to detect as little as 2% excess moisture.