In recent years, parts of the brickwork of dozens of flat end walls have collapsed. In most cases this was caused by corrosion of the steel cavity ties. As a result of these incidents, the Ministry of Infrastructure and the Environment (called VROM at the time) has advised the municipal authorities to address owners and managers of high-risk buildings, to assess these facades to determine the risk of brickwork collapsing.
In 2012 SBR published the ‘Constructive Safety of Existing Brickwork of Outer Cavity Leaves’ protocol. This protocol states how the risks of various facade constructions can be prioritised and provides recommendations regarding the method for inspecting and testing the facade constructions. The protocol was drawn up by TNO. BDA Geveladvies and Adviesbureau Hageman provided the inspection reports that were used to draw up the prioritisation models. Over the years, BDA Geveladvies has gained vast experience investigating end walls.
Risks are increasing
The risks of end walls collapsing are underestimated by building owners. Despite warning letters, publications and articles, the number of inspections being performed is still relatively low. As a result, the number of damage cases will increase in the next couple of years.
The objective of the inspection is to establish the structural safety of the brickwork facade constructions, allowing a long-term maintenance plan (LMP) to be drawn up. The strategy here is to postpone repair work for as long as possible in order to keep the annual costs as low as possible. Table 1 presents an example of an LMP. To draw up an LMP it is important that the inspector/consultant has sound constructive knowledge. By correctly judging the risks, the time of repair can be pushed further back. Postponing repair work does lead to higher overall costs, but the expenses are not incurred until much later. By spreading the costs, budgets can be reserved and the annual repair costs can be reduced.
For more information, please contact BDA Geveladvies.