The use of appropriate conservation techniques is critical to the preservation of buildings. This important Digest gives advice on how to apply safe, effective, appropriate and enduring conservation techniques to brickwork, blockwork and terracotta. It outlines how to identify the units and associated mortars, and how to diagnose the causes of soiling and deterioration. It advocates avoidance of cleaning to optimise the life of masonry but outlines its use where appropriate. Appendices list standards for testing masonry units and describe two methods of testing the strength of masonry and stress in masonry.

The first part of the Digest (published in 2008) dealt with conservation of stonework, and the third part (in preparation) will cover renders, plasters and stucco. The companion Digest 502 explains the principles of the conservation of masonry in historic buildings.

Illustrations
2 line drawings, 22 photos

 

Pages
24pp

 

Contents

 

Identifying existing brick and mortar

Properties and identification of existing manufactured units

Properties and identification of mortars

 

Causes of deterioration

Diagnosis (Staining and discoloration of clay brickwork. Staining of masonry made with concrete, reconstituted stone and calcium silicate units)

Decay (Clay brick masonry and terracotta. Concrete and calcium silicate unit masonry. Structural deterioration from movement or over-stressing)

 

Remedial work

Cleaning and decontamination techniques (Washing. Mechanical/abrasive techniques. Chemical methods. Poulticing. Removal of plants/biological growths. Laser treatment. Choice of cleaning method. Good practice)
Trial cleaning techniques and assessment procedures

 

Repairs

Repair materials

Availability of replacement masonry units and mortar

Repair methodology (Access. Choice of replacement materials. Trial repairs. Health and safety. Wall format, bond pattern and pointing style. Cutting. Finishes. Fixings. Terracotta, faience and other decorative ware)

Repair techniques (Demolition/reconstruction. Replacement of single units. Cutting back and replace¬ment. Plastic repairs. Terracotta sections. Rebedding with mortar. Deep repointing. Conventional pointing)

Specialised materials and techniques (Over-dressing. Consolidants. Grouting. Re-glazing terracotta units)

Dealing with damp problems

Maintenance schedules and optimisation of durability

 

Conclusion

 

References

 

Appendices: Test standards. In-situ test methods

Other publications that may also be of interest
Conservation and cleaning of masonry: Part 1. Stonework
Principles of masonry conservation management