HENSALL | Group of Building Services Companies |
T: +44 (0) 1977 661 318 | E: info@hensall.com


We first started working on HMP Liverpool in 2018. Working with ISG through the MOJ framework, we successfully completed the refurbishment of one of the wings in 2020.

As most of the buildings were constructed between 1848 and 1855, there can often be unforeseen challenges. Our strong performance and ability to overcome these challenges allowed us to secure additional wing refurbishments and we will now be on site until 2025.



Design in conjunction with Project Team including working drawings, Site setup, surveys, procurement, asset registers, O&M manuals, Staff training, Testing commissioning and documentation.


Mains distribution system, main MCCB panel, distribution boards, containment for all services, earthing, LED lighting installation, Cell lighting, small power, machinery supplies, power to general areas , fire alarm system alterations, General Alarm alterations,CCTV, IT, Lightning protection upgrades, mechanical supplies, testing and commissioning, IT installation including CAT 6 cabling, security, CCTV, aid alarm.


The provision of HVAC and domestic services to 7no prisoner wings, along with the refurbishment of critical plant areas whilst maintaining normal operation for the prison management team and inmates.
Works include the replacement of centralised boilers and associated plant and equipment, along with the lining of existing flues due to existing building restrictions.
Wing refurbishment works include the replacement of all LTHW and domestic plant to provide effective heating and potable water supplies to each prisoner cell.
LTHW works involved the installation of pipework and pumps to each wings plant zone which in turn feed heat emitters within the wing, consisting of radiant heating coils to common areas, specialist NOMS compliant radiant security panels to the prisoner cells, and standard/LST radiators to staff areas.
HVAC works included the installation of WC extract to each cell and heat recovery ventilation to the inmate shower blocks. All ventilation plant has been provided with attenuation to reduce noise pollution into the wing or external areas. Destratification fans have been provided to ensure air is effectively circulated through the central atria which rises through 6 stories.
Domestic works include the installation of DHW PHX’s and storage vessels to each wings plant area, distribution pipework and associated sanitary equipment. All sanitaryware installed as per NOMS standards with no ligature points, with the exception of staff sanitaryware.
A building management system has been installed and commissioned to ensure effective and efficient operation of all HVAC and domestic systems to suit the requirements of the prison.










HMP Liverpool is a Category B Victorian prison comprising of 8no wings, with capacity to incarcerate up to 1,370 inmates.

Whilst individual parts of the prison had undergone some form of refurbishment since the original construction, the typical standard was poor and required upgrade to meet the current MOJ and NOMS standards.

Hensall were employed on behalf of ISG to complete the specialist design, installation and commissioning of all Mechanical & Electrical services as necessary during the total refurbishment of all 8no wings, inclusive of their associated plant areas.

Works completed include the de-commissioning of all M&E systems to allow the refurbishment works to commence, subsequently followed by the installation of new systems to serve the prisoner and staff areas. Mechanical systems installed include sanitary systems, LTHW heating systems & ventilation systems, all of which are controlled and monitored by dedicated building management systems to ensure efficient operation. Electrical systems installed include LV distribution, small power, lighting, data, general alarms, fire alarms, CCTV, AV, tamper alarms, and lighting protection.

Although all works were completed within temporarily decanted wings, our project team had to work closely with the main contractors management team and prison staff to ensure works could be completed in a safe and efficient manner. Prior to commencement of the project, our team were faced with the challenge of carrying out surveys within various live prisoner environments.


“Hensall Mechanical Services Limited have worked for ISG Construction for the last ten years across a number of projects. They are a key trusted supply chain partner of our Business and have built a strong relationship based on providing a Quality service.

They work across all sectors within ISG and on key projects within the MOJ sector, where their project values range from £1m to £20m on Major refurbishment works.

They have recently undertaken a number of public sector decarbonisation schemes with ISG in the leisure sector and are currently working on a number of live MOJ and Leisure projects in the North.

Hensall are a business I would highly recommend, they are professional, approachable and have a can-do attitude to problem solving, the quality of their installations is second to none with very few issues post PC.”

Andrew Beaumont MCIOB | Operations Director | ISG