 In 1716 he replaced James Gibbs as one of the two surveyors to the Commissioners for the Building of Fifty New Churches – the other being Nicholas Hawksmoor.He designed one church for the commissioners – St George's, Hanover Square – and collaborated with Hawksmoor on the design of two others, St John Horsleydown in Southwark and St Luke Old Street.At St Alfege's Church in Greenwich, he recased the medieval tower and added a steeple in 1730, the rest of the church having been entirely rebuilt by Hawksmoor for the commissioners in 1712–14.