Conserving value is harder than creating new.

Every art form has its old masters, including the arts of architecture and structural engineering. Complex constraints affecting the renovation of listed buildings, historic neighbouring structures, or the need to understand historic building procedures, can quickly strike awe into the engineer. 

Or they can challenge the engineer to bring out the best in his or her creativity, e.g. in the consideration and selection of modern procedures for complex retaining measures on listed facades, or for setting out new staircases to meet the needs of new changes in use.