Frequently, the best way to ensure the preservation of a heritage building is to use it, and more often than not the use for which it was designed will be the most suitable. In this regard a recent appeal in Sussex where the functioning of a working windmill was a matter of concern is an interesting case.
In this case (DCS Number 400-023-236) the extension of a house sited 20m from the listed windmill was denied permission because it would result in wind shadow. The windmill was in working order, was used to produce flour and was a visitor attraction, the inspector noted. He held that the functionality of the mill was an important part of its significance. He noted that the Society for the Protection of Ancient Buildings had undertaken modelling to demonstrate the effect of the development on wind flow. This demonstrated that the development would cast a wind shadow that would cause a 12 per cent loss of operational area for the mill.
Given the size and height of the proposed development and its proximity to the mill the inspector was concerned that it would, in combination with other development that had taken place in the area, have clear potential to further compromise the working of the windmill and its functionality. He also considered that the increase in height of the dwelling and the side and rear extension would be large and prominent features in the setting. He acknowledged that the proposal would greatly improve the accommodation within the house, providing a high standard of family accommodation. This would be of public benefit, he judged, but it would be limited, and he therefore gave it limited weight.
The inspector concluded that the harms to the setting and significance of the heritage asset would be less than substantial, and he gave great weight to those harms. The limited weight that he gave to the public benefit was not sufficient to outweigh this, he decided.
Further information concerning the duty to preserve listed buildings can be found at section 27.111 of DCP Online.