The incumbent and churchwardens sought a faculty to replace existing cast-iron downpipes and hoppers on a Grade II* listed church with high-density polyethylene (HDPE) substitutes. The initial cost of HDPE goods was approximately half that of cast-iron equivalents and the petitioners submitted that this, taken with a reduced level of maintenance required for HDPE goods, meant that over time the total costs involved would be significantly less if HDPE were used. The Diocesan Advisory Committee did not recommend the proposal. It considered that HDPE was an inferior material to cast iron in terms of both its longevity and its ability to be repaired, and that it was unsuitable for use on a listed building. Historic England considered that HDPE rainwater goods would be visually less satisfactory than cast iron and would detract from the quality of the building, that their use would be inauthentic, that their life expectancy was unknown and that the proposal would materially harm the significance of the building. The Church Buildings Council expressed concern that HDPE would become brittle in time and degrade. The petitioners stated that evidence from the United States demonstrated that HDPE was not subject to significant degradation and could last many decades. The chancellor considered that the current rainwater goods made a modest contribution to the architectural qualities of the building, that the difference between HDPE rainwater goods and cast-iron equivalents was immediately noticeable, that HDPE appeared artificial and that it would be an anachronistic feature on an historic building. Applying the Duffield guidelines, the chancellor held that the proposals would result in harm to the significance of the church as a building of special architectural and historic interest, albeit not serious harm. The justification advanced by the petitioners – namely the comparative cost of HDPE as against cast iron over a long period of time – had been rejected by each of the expert statutory bodies. The church's inspecting architect had not been asked for advice about the proposals and there was no evidence from a buildings specialist which supported the petitioners' proposal to use HDPE. The petitioners were therefore unable to provide clear and convincing justification for the harm that would result from their proposals. In any event, a cost saving alone would not normally amount to justification for harm to a listed building and such a modest level of saving as envisaged by the proposals (£242 per year over 80 years) carried very little weight. In the absence of any public benefit from using HDPE, the petitioners were unable to overcome the strong presumption against proposals that would harm the special character of the listed building. The petition was dismissed. [Alexander McGregor]