The designer of the Holy Trinity Church pioneered the use of what material in church building?
John William Whittaker:  One of the churches instigated by Whittaker was Holy Trinity Church, a Commissioners' church designed by his cousin, Edmund Sharpe, who was then at an early stage in his architectural career. Edmund Sharpe:  Sharpe's main focus was on churches, and he was a pioneer in the use of terracotta as a structural material in church building, designing what were known as "pot" churches, the first of which was St Stephen and All Martyrs' Church, Lever Bridge.
terracotta