Forefront employs around 350 staff operating in the south east from its head office in Leigh-on-Sea.
The utility contractor was founded in 1995 and focuses on the replacement of gas mains and emergency repair services for National Grid and Southern Gas Networks in London and the South East.
Roy Harrison, chairman of Renew, said: “The acquisition of Forefront takes the group into a new sector within the energy market.
“As part of the Renew Group, Forefront, which has a leading industry reputation, will continue to develop its strong, independent brand.
“The gas mains network replacement programme provides Forefront with long term visibility and excellent growth opportunities.”
The acquisition has been funded with a four-year term loan of £12m provided by HSBC Bank.
Forefront’s revenues stem from the national 30-year iron gas mains replacement programme with polyurethane mains.
The contractor specialises in both low and medium pressure outlets up to 48″ diameter.
It achieved sales of £23.3m and a break-even operating result last year as workflow was reduced prior to the commencement of a new framework for National Grid.
Margins are expected to return to more historical performance levels of 6.3% as workloads improve again.
Forefront was owned by Harwood Capital and some other interests.
Its founder and chief executive, Bradley Beard, and Forefront’s management team will remain with the business, reporting to Renew’s chief executive Brian May.