The practice has much experience of working on or adding to buildings that are listed as being of architectural or historic importance, including buildings listed grade I. Much of this work has been carried out for Cadogan, one of the large London estates, with substantial property holdings in Chelsea. The sympathetic approach that is adopted for the alteration and refurbishment of listed buildings is highly regarded by planning officers, which is helpful when applying for listed building consent for new projects.

David Le Lay acts as Church Architect for several churches and has been employed to undertake Quinquennial surveys and all types of work to church buildings.