The downturn has been sharpest in North East of England, Yorkshire and Scotland with residential heating and ductwork sectors feeling greatest pressure, according to a new industry survey.
But firms in the North West & West Midlands, London & South East, and the Eastern Counties & East Midlands, together with the larger contractors have also seen an improvement in enquiries.
The M&E sector has suffered several high level contractor collapses in 2012.
And specialist contractors warn that late payment, zero or very poor margins and main contractor insolvency remain serious threats to their business over the next six months.
Half the 228 contractors surveyed by trade body B&ES said tender prices were lower than they were six months ago – and that, while labour costs had remained more or less static, there had been a significant increase in the cost of materials.
The low levels of business saw direct employment fall across the building services industry, and 61% of firms said they had not taken on an apprentice or trainee in the past year.