R. J. M. SUTHERLAND Harris and Sutherland, Consulting Engineers

The adaptation of old masonry structures is posing increasing problems for designers and building control officers. To what extent is compressive stress relevant? How much effect has workmanship on the load-bearing capacity of thick, lime mortar walls? BS5628 is scarcely relevant. Is some research needed on the strength and overall robustness of such walls? Is vertical cracking significant and if so in what circumstances? Given known bad workmanship is grouting beneficial or in itself dangerous? This is a paper of questions rather than answers but questions which merit further discussion.