The Plessey Centre – A Modular Build Solution for Community Mental Health

A case study detailing NTW Solutions first modular building construction project.

Every major review of the construction industry has in some way recommended a move towards offsite construction. The House of Lords Science and Technology Committee published a report in July 2018 reiterating that off-site manufacture (OSM) has the potential to increase productivity, improve quality and reduce environmental impacts, as well as reducing the demand on labour. The construction industry has an ageing workforce and is losing traditional skills that will only be exacerbated by Brexit.

NTW Solutions has a business objective to move to greater use of off-site manufacture and this approach has been used in many capital projects with the manufacture of structural frames, en-suite pods and fitted furniture built off-site but not yet a full building solution until faced with a refurbish or replace decision on the Community transformation programme. The Plessey Centre in Blyth, is part of the Northumberland Psychological Wellbeing Service, an outpatient service ran by Northumberland, Tyne and Wear NHS Foundation Trust. The building was past its design working life in many instances, (Roof, Windows, Heating and Electrical systems) and the current building had little architectural merit to retain.

Most of the budget would have been spent on dealing with backlog maintenance issues and the real cost of a renovation would not be known until the layers of the building were removed and the age and condition of the various components that make up the building assessed. Detailed investigations that followed revealed that the existing structure could not evolve into the desired result, at this point, it became clear that the option to demolish and start again had emerged.

As such, a new build permanent modular construction (PMC) option was developed which will comply with all current regulations including energy efficiency and emissions. PMC is a method of construction, not a building type. It greatly differs from temporary buildings, such as construction trailers or mobile homes. Modular buildings are built with all the same materials and to the same building codes and architectural specifications as onsite construction, just completed in an offsite, quality controlled environment. Far from the preconception of drab, box-like buildings of the past Modular buildings can provide stylish, spacious space solutions on a limited budget.

Working closely with our construction partners Sir Robert McAlpine and principal supply chain member Acrol the purpose-built single storey building design comprises of consultation rooms, staff offices and hot desk facilities was manufactured off site and then lifted into place. The main design driver was to make the modular structure feel more grounded and permanent. A minimum ceiling height of 2.7m and a minimum corridor width of 1.8m was established to give the building a spacious feel. The main materials chosen were Dura wood-plastic composite cladding and brick slips. Both materials were chosen for their robustness, low maintenance and the ability to be assembled off-site. Together they animate the facade and bring the modules together into a coherent whole. The striped effect created with interchangeable Dura panels, using grey and charcoal colours adds interest and helps to elongate the facade. The veneer nature of the brick cladding was exploited through the use of soldier coursing, which again emphasises the verticality of the Dura cladding. Window reveals are highlighted in a dark orange colour.

The Community Mental Health building was made up of ten individual, factory-built modules of 30m2 each to form a complete rectangle building of 300m2. The Electrical, heating and domestic water services were integrated into each module part. The modular new build has a design working lifespan of 50 years, its external skin 30 years, its mechanical systems 20-30 years, electrical systems 20 -30 years.

The manufacturing timeframe was 8 weeks with 8 weeks of construction on site which included a new car park, water and electric infrastructure works. While the building was being manufactured off-site, groundwork on site ran concurrently, speeding up the build programme. This reduced the time spent on site and therefore also reduced the disruption caused to local residents. The building was occupied 24 weeks after business case approval.

The modular build option is a total cost was £761,872.37 against the original allocated refurbishment budget of £600,000. A view was taken at business case approval to procure for whole-life value rather than lowest cost. In comparison, a traditional new build was estimated at £1,050,000 with a programme of 32 weeks. The modular build worked out 50% quicker on duration and 28% cheaper than a traditional build option.

John Carson, Head of Capital Development and Planning for NTW Solutions commented

 “The building is a spacious room with a bright exterior and it seems to have made a positive impression on the building’s users. We have had great feedback from the Community Team staff and are delighted with the outcome. When looking to replace old buildings, modular buildings provide a dependable, economical solution, without compromising on aesthetic appeal.”