TCL Granby made an operating profit of £1.4m last year on a turnover of £16m. It has long-term maintenance contracts with clients in the telecoms and banking sectors as well as several embassies, mostly in London.
Curzon, which has a turnover of £40m, was the management buyout vehicle set up by Freeborn when he lead the buyout of Jarvis Newman from its parent company Jarvis last year.
TCL Granby has 110 staff and has offices in Mitcham, Surrey, and the City of London. Managing director Terry Dunne will join Curzon.