DEFRA Engineering Delivery Framework

Weybridge, Surrey

Walter Lilly are currently appointed as a contractor on the Engineering Delivery Framework with the Department of Environment, Food and Rural Affairs (DEFRA) for refurbishments on its APHA Weybridge site. Walter Lilly has successfully secured a position on two Lots.

In Lot 1,  Walter Lilly is one of three contractors selected to work on designing, building and installing works inside a containment environment, and also testing, commissioning and validating newly installed equipment in a CL3 or CL4 environment.

Walter Lilly is also one of three contractors chosen for Lot 2, in which works include designing, building and installing general accommodation and site infrastructure projects which do not require working in high containment environments.

DEFRA’s Weybridge site is a world-class scientific facility with more than 20 high containment laboratories over a main site of 100 acres.  As a wide variety of pathogens are contained on site, Walter Lilly’s experience and expertise in dealing with designing, building and installing works within a containment environment was crucial in being selected for the framework agreement.

Since the Engineering Delivery Framework commenced in 2017, projects have included:

  • Internal refurbishment works to relocate two electron microscopes, and the conversion of a room to house them. Works included the installation of suspended ceilings, new internal doors, anti-static flooring, black-out curtains and new laboratory furniture – all required in order to maximise the performance of the electron microscopes.  A plant room extension to house the associated services equipment was also built.
  • A pilot upgrade to Building B265C’s control systems, replacing the old installation of building control systems equipment which had reached its end of life. The aim was to retain as much of the old installation as possible, reusing the field devices such as motor drives, sensors and actuators where possible, whilst removing the outdated BMS controllers from their housings and fitting new controllers in their place.  Upon successful completion of the pilot upgrade, the project will be rolled out to other buildings across the site.
  • Demolishing the B90 building in preparation for the upcoming APHA incinerator upgrade.The work was complicated by the presence of asbestos in the existing B90 building which had to be removed by a licensed contractor prior to the actual demolition taking place.  As the building was surrounded on three sides by other buildings that remained in use, considerable care had to be taken to avoid disrupting the day to day operation of the site’s surrounding area.
  • Construction of two temporary service yards to prepare for the APHA incinerator upgrade.

Project credentials


Weybridge, Surrey




Project Manager: Currie & Brown
Architect: Architon
PQS: Rider Levett Bucknall
Structural Engineer: ARUP, Ross and Partners
Services Engineer: ARUP, MG Partnership