ISG has initiated works on two projects, valued at a total of £135m ($171.84m), at HMP Guys Marsh in Dorset and HMP Liverpool in the UK.  

These projects are part of the UK Ministry of Justice's (MOJ) overarching £4bn investment programme aimed at increasing the country’s prison capacity by 20,000 places.  

The contracts for these schemes were secured through the Crown Commercial Service framework. 

ISG justice sector director Alistair McNeil said: “Through our work with the MoJ and other contractor partners, working across the framework, we are consistently delivering better-built outcomes, benefiting the prison population and wider society. 

“Our projects at HMP Guys Marsh and HMP Liverpool not only address a need for prison places but will also support government carbon reduction targets, delivering buildings that cost less to run and maintain in the future.”   

The £79m project at HMP Guys Marsh involves constructing two new two-storey house blocks, an extension, and a refurbishment programme.  

The development aims to boost the prison's capacity by 31%, with one house block providing 122 cells and the other 59.  

These blocks are designed to be net-zero carbon in operation and are expected to achieve a Building Research Establishment Environmental Assessment Methodology (BREEAM) Excellent environmental performance rating. 

The house blocks will also have air-source heat pumps and LED lighting. 

Meanwhile, at HMP Liverpool, ISG is building on a six-year partnership, undertaking a £56m refurbishment to support the prison's transition from a Category B to a Category C facility.  

This refurbishment includes electrical infrastructure upgrades, new efficient boilers, restoration of all wings, and a new workshop.  

Last March, ISG was selected for the MoJ's five-year, £2.5bn constructor services framework and is currently upgrading HMP Birmingham.