No money will change hands but four Mott directors will become DL&E partners. The name Mott Green & Wall will remain, although its surveyors will form a joint team with DL&E's 25 M&E specialists.
London-based Mott Green & Wall, which was founded in 1972 and has 30 staff, is one of the few firms to offer a speciality in M&E quantity surveying.
Most larger quantity surveyors offer the service as part of an overall package, but Mott is often taken on separately to provide cost advice on M&E installation.
The firms hope that they will win more office, petrochemical and pharmaceutical work by offering a joint service.
We are doing this to open doors. We had been successful but now we can hit a new market
Ken Cheshire, Mott Green & Wall
DL&E senior partner Paul Morrell said: "There is a shortage of mechanical and electrical quantity surveyors, and we recognised the need to strengthen what we offered, so I went to talk to [Mott Green & Wall joint managing director] Ken Cheshire.
"It's not something you can move a conventional quantity surveyor on to. Where we have done it internally, it has taken a lot of training.
"From a cost consultancy point of view, you can only advise on how to do it better if you understand how the technology works." Mott Green & Wall is working on 150 000 m² of projects, including the redevelopment of the Treasury headquarters, the Tate Gallery of Modern Art at Bankside and the Royal Opera House.
Cheshire said: "We are doing this to open new doors. We had been successful on our own, but with DL&E, we can hit a new market." He said M&E prices were not moving upwards sharply, despite anticipated shortages of M&E contractors. Cheshire said: "Contractors are still cutting each others' throats. It's very competitive." Mott directors Barry Nugent, Nick Mulholland, John Dedman and Cheshire will become DL&E partners. Director Tony Lonergan becomes a consultant to DL&E and Mott.