St Margaret's Church, where the explorer James Cook married in 1762, dates from the 15th century. The Curfew Tower, of the same period, still guards the entrance to the churchyard.

RWA have a long association with St Margaret's which is Grade I listed and adjoins the ruins of Barking Abbey, which is a scheduled ancient monument.

Ronald Wylde was a churchwarden for many years, helping to realise the attached Church Centre and providing the practice with a unique insight into the difficulties of acting as client.

More recently RWA have supervised repairs to the outer north aisle roof following extensive fire damage and carried out other works of repair and restoration.