The project, coordinated by the BBC’s Children in Need and DIY SOS, was delivered by a multi-disciplinary project team. MES Building Solutions’ role was to ensure Part L compliance to certify that the build was in line with the government’s plan for net zero.

The extension, located alongside The Joshua Tree’s existing support centre on Dalefords Lane in Northwich, provides new counselling spaces, gym facilities, therapy and massage rooms, and associated support areas for families affected by childhood cancer.

With key elements designed and constructed in a matter of days, the project demonstrated how building performance modelling can support regulatory compliance and occupant comfort, even under extreme time pressure.

Simplified Building Energy Model (SBEM) calculations and air-tightness testing were undertaken to help demonstrate compliance with Part L, with a focus on delivering a sustainable and energy-efficient building that will be used by The Joshua Tree to support vulnerable children and their families.

IES Virtual Environment (IESVE) software was used by MES to support elements of the modelling process. ModelIT, IESVE’s geometry creation application, was used to develop and adapt the building geometry and zone the model by room type, with the firm’s VE Compliance application defining construction elements, building services and compliance inputs.

Geometry was imported from SketchUp to accurately represent the building’s angular form and complex roof structures, with efficient data reassignment across zones enabling rapid updates as the scheme progressed at pace.

Tommy Jackson, sustainable buildings consultant at MES Building Solutions, said: “This was one of the fastest-moving projects I’ve been a part of, delivered by a massive team working under intense time pressure. The challenge was to keep pace with design changes while still maintaining confidence in the compliance position. IESVE was one of the tools used to help us respond quickly, update the model accurately and provide clear compliance feedback, which was important given the timescale.”

Rich Driffield, CEO at The Joshua Tree, said: “Our families need spaces that feel safe, calm and welcoming all year round. Seeing the building come together so quickly was extraordinary, but what mattered most was knowing it had been properly thought through by the whole project team and would be comfortable from day one.

“As a charity, we now support families across the UK through a range of on-site and outreach activities. With our main centre fully developed, we have laid strong foundations for the future of The Joshua Tree and, most importantly, are now able to support even more families affected by childhood cancers.”

Niall Gibson, head of EMEA at IES, said: “This project is a great example of what can be achieved through close collaboration. Even under extreme time pressure, building performance and compliance don’t have to be compromised. With the right tools and a collective approach, it’s possible to support rapid delivery while still ensuring buildings perform as intended for the people who rely on them.”