Heritage - an environmental benefit.

Today I came across some photos on the BBC website of some at risk heritage assets in the UK.

http://www.bbc.co.uk/news/in-pictures-15351162

Preserving these is sensible from both a historic, educational (to demonstrate skills of our ancestors) and environmental.  The latter is sometimes forgotten but carbon, in both construction and embedded materials can be possibly saved by converting existing historic buildings.

This, of course, has to be be within the law but we don't want progress to be hampered by unused "historic" buildings which nobody wants to save and have no real social benefit. A prime example of this is in Blackburn Lancashire, where an urban ringroad connecting a multi-million pounds railway roadbridge has been quashed by a protected building which has been empty for about 50 years and in danger of falling down. Surely is it's to be retained for heritage purposes it's either useful or it can become a negative feature. In this case in Blackburn, the building causes traffic mayhem as a dual carriageway, instead of passing straight onto the aforementioned bridge, turns into a one way single road, on which traffic crawls through some of the less welcoming of the town's streets.