The 51 churches in the City of London rebuilt by Sir Christopher Wren after the Great Fire in 1666 are this year commemorating the 300th anniversary of Sir Christopher’s death.

Part of the activities in what is being called WREN300 is a series of workshops and presentations about the conservation skills used in the maintenance of the churches, which include Wren’s masterpiece, St Paul’s Cathedral.

The first of the workshops, involving the stonework of the churches, were presented last week at St Bride’s Church in Fleet Street by stone and conservation specialist Cliveden Conservation, which is among the companies that help to keep the churches in such good condition.

The first workshop on 12 April focused on stone cleaning, showing how the superheated water and laser products of, respectively, Restorative Techniques and Terra Measurement can be used to clean stonework.

There were also demonstrations of the HD3D digital surveys of the churches being carried out as part of the WREN300 programme by Terra Measurement using photogrammetry and point cloud laser technology, creating millimetre accurate digital twins of the churches.

In the evening, Oliver Caroe, one of the country’s foremost ecclesiastical architects who is the Surveyor of the Fabric of St Paul’s Cathedral, discussed the stonework renovation and alterations at St Paul’s, including the new accessibility ramps built by Stonewest.

Presentations about the broader use of stone in sustainable ways, particularly for new-build, were given by stonemason extraordinaire Pierre Bidaud of The Stonemasonry Company and engineer Steve Webb from Webb Yates.

They provided ‘A walk through the New Stone Age’, offering solutions in stone construction, notably with the use of post-tensioning, in the context of today’s social and environmental challenges, not least global warming. The evening rounded off with an opportunity for the audience to talk to the presenters informally over glasses of wine.

The following day, visitors were able to have a go at lettercutting, marking out and lime pointing during a stonemasonry experience day, again at St Bride’s, with Cliveden explaining about mortar repairs, indent repairs, repointing, mortar and stone analysis.

These and future workshops covering the conservation of metal, glass, wood, and plaster/paint are free, but the churches ask anyone wishing to attend to register, so they know how many people to expect.

There are various other events taking place as part of WREN300, including a Wrenathon of choirs from across the City of London and beyond in a 12-day festival in June taking place in several of the Square Mile Churches.

Details of all the events and booking for them (some are not free) can be found on the Square Mile Churches’ website.

Below are some photographs from Cliveden's events.