1973 

John Ellison founded an M&E company specialising in local, mainly council, heating and ventilation contracting. 

Projects included school boiler re-tubing and replacement, along with the associated electrical works.

1984 

Aiming to stand out from other contractors, John designed and built the UK’s first mobile boiler hire unit. 

This innovation allowed temporary heat provision during school boiler replacements, enabling daytime work rather than out-of-hours operations.

1988 

As local contracting work expanded, the company undertook a major restructure. 

A partnership was formed with French boiler manufacturer De Dietrich, making the company the sole UK assembler, commissioning agent, and service provider for their plant. 

Ellison teams were trained in Strasbourg for all related operations. 

It was at this time that John began developing the concept of an off-site manufactured Packaged Plantroom.

1989 

Tesco — the largest potential client for off-site manufactured plantrooms — asked John to survey mechanical plantrooms across the UK that were suffering from overheating issues. 

After completing surveys at around 22 sites, John presented a detailed report highlighting both strengths and weaknesses. 

Recognising an opportunity, he advanced the idea of the Ellison Containerised Plantroom.