Heating in historic churches is generally designed for the comfort of the congregations rather than the conservation of the building fabric. It is usually intermittent, resulting in periods of relative microclimatic stability interspersed with fluctuations, which can prove extremely damaging to the sensitive building fabric.

Tobit Curteis Associates was commissioned by English Heritage to undertake a programme of research in conjunction with their Building Conservation and Research Team to investigate methods by which thermal comfort can be provided to individuals using the church while at the same time minimizing the deleterious impact on the historic fabric.

The main field study was undertaken at St Botolph's Church in Hardham which contains the most important scheme of early 12th century paintings in England. These are actively deteriorating largely as a result of the effects of the internal microclimate and the existing heating system.

It is intended that the results of the research should provide a direct benefit to a wide range of churches with sensitive fabric which suffer deterioration from this particular source.