Turnover edged up 6% to £1,052m as the builder diversified its business to ride out the extended downturn.

But pre-tax profits in the year to December 2011 dropped by a fifth to £21m as building margins suffered from the industry-wide squeeze.

Group chief executive Rick Willmott said he had targeted the green economy and aimed to rebalance public and private sector work for future growth.

The firm’s new Energy Services arm secured its first major green deal work to retrofit homes in Wales.

Willmott said: “I’m delighted we’ve secured a £17m contract to manage the retrofitting of 2,000 homes in Wales for the Welsh Assembly that will take hundreds of families out of fuel poverty.

“This follows our selection by DECC to be a Pioneer Green Deal Provider, which goes live in the autumn, and reflects our investment in the development of processes and skills to play a significant role in improving the energy efficiency of property through mechanisms like the Green Deal.”

He added the new Regen division was building a £500m pipeline of development work, which would boost the building business over coming years.

This will build 700 homes at Dee Park estate in Reading over eight years and over 100 homes at Brenley Park in Mitcham.

“Our ambition and skill-set to undertake mixed-use development is further underlined by our position as preferred bidder with Morrisons to develop a 1.5 hectare site in Walthamstow town centre into retail and residential use,” added Willmott.

“We also secured the £60m residential element of a regeneration in Greenwich as part of a development agreement with Cathedral Group and Development Securities which will be on site during 2012.

“We want to work in partnership with local authorities to help them realise the asset value and economic potential of their land.”

He said Willmott Dixon had developed a model for the private rented sector that could help local authorities and private land owners get the best use of land to generate income.

“Our goal is to establish a portfolio of homes for market rent in joint venture with land owners and we are in detailed talks with Birmingham City Council, which this year gained cabinet approval to join the LLP we have created with WM Housing Group to build 400 homes near the centre.”

Just over three-quarters of budgeted work has been secured for this year and the secured order book stands at £1.18bn.

Willmott said: “While our contracting, housing and interiors’ companies are maintaining market share, it remains a tough environment with reduced availability of work and increasing margin pressure.

“We are active on a number of major frameworks including Scape where our standardised concept Sunesis, developed in partnership with Scape to cut the cost of new schools, has already created over £100m of inquires, with many projects now at planning stage and a number under construction.”

Willmott Dixon plans to roll out a standardised design to the leisure sector this summer.

Repairs and maintenance company Willmott Dixon Partnerships had one of its most successful years, securing long-terms contracts with Home Group, Affinity Sutton, ACIS and Guinness South.

The business is now responsible for the maintenance of over 150,000 homes across the country.