Once the demolition was complete, the building was essentially four walls and no roof, plus the attached Sunday School. The building of the steel frame served the dual purpose of providing stability to the original walls as well as providing the new accommodation within the building.
The steel frame was very complex as it had to fit round the existing features of the walls which were neither particularly straight nor particularly vertical, particularly the end gable which leaned out considerably. The walls needed to be tied to the steel frame to hold it all together.
The Sunday School was simpler but still not trivial. The single internal floor was taken out and two floors were put back in, with a number of steels being inserted to replace large timbers trusses in inconvenient places.