Cavity Wall Tie Replacement, Belfast

Belfast, Co. Antrim, NI
Stronghold Preservation were requested to carry out a survey to inspect a crack in a wall, in this 2 storey red brick house in Belfast. The house is a cavity wall construction. To assess the condition of the wall ties, a brick was removed by a Stronghold Preservation surveyor. The wall ties visible were found to be mild steel, rusted and significantly corroded. An inspection at roof level found that there was vertical expansion of the bed joints. The crack in the wall was therefore attributed to the corroding cavity wall ties.

Further Information

Identifying Cavity Wall Tie Problems

Historically, mild steel cavity wall ties where used in construction; as mild steel is prone to rusting, over time, the wall ties corrode (rust), and expand.  This expansion of the cavity wall ties in turn causes expansion of the bed joints, which can cause the walls to crack and bulge.  A visible lift at eaves level, cracks in the walls, and in severe cases the outer blockwork leaf falling, are all signs and symptoms of failing cavity wall ties.

Stronghold Preservation removed the existing rusted wall ties, and replaced the mild steel ties with stainless steel ties.  The mortar beds were repointed.