(Sharecast News) - Redhall warned investors on Wednesday that full-year results would be "materially" below the engineer's previous guidance as a result of project delays and slower-than-expected efficiency gains.Redhall assured shareholders that its transformation strategy, focused on "operational excellence" and expanding its pipeline of opportunities in target markets had Redhall poised to deliver "steady" growth in 2019.However, delays on a number of key projects outside of the group's control and slower than expected operational efficiency gains meant the board was much more cautious of the immediate future, even as overall market conditions remained robust in the majority of its core markets. The AIM-listed outfit provides design, manufacture, installation, testing, maintenance and decommissioning services to the nuclear, oil & gas, defence, infrastructure, telecom, petrochemical and food process sectors,As of 31 August, Redhall's order book was £23m, down from £29m at the end of March."The order book is supported by a strong pipeline of opportunities," Redhall said.Reduced market activity at Redhall Networks resulted in lower revenues in the second half of the year. However, the imminent rollout of Redhall's 5G technologies gave the firm hope of an increased demand in 2019."The board anticipates that the group will deliver steady growth in 2019 supported by robust market demand and a strong pipeline of opportunities, coupled with an improvement in operating margins as the benefits of the transformation strategy start to be delivered."As of 1200 BST, Redhall shares had tumbled 32.44% to 4.56p.