Don’t Park the Concrete Maintenance


Residential and mixed-use developments often have underground car parks and it is important that these functional parts of the building are not pushed down the priority list when it comes to maintenance.

In this article we will highlight some of the main defects associated with concrete car park.

Typical Defects

Whilst other concrete defects exist, the following are the most common we come across as Chartered Building Surveyors:

  • Carbonation – Carbonation is almost impossible to avoid where concrete is exposed to the elements. This defect manifests itself with spalling concrete, so whilst carbonation affects the robustness of the concrete, it also presents a health and safety issue through falling lumps of concrete.
  • Calcium Chloride – Until 1977 calcium chloride was often added to concrete as an ‘accelerator’. Calcium chloride can also be found in concrete in car parks from de-icing salts that are either applied to car park surfaces in cold weather or brought in from externally by cars and foot traffic. This give rise to ‘chloride induced corrosion’, which can result in a reduction in the structural strength of concrete.
  • High Alumina Cement – this material results in a loss of strength, particularly in high moisture environments. Its use was banned in 1976, so buildings constructed after this date are unlikely to contain this material.

What Does This Mean for Property Managers?

The good news is that these concrete defects can be diagnosed and repaired. There are a number of different solutions available which are often dictated by the type and extent of the defect and location.

At Hamilton Darcey we recommend regular inspections of concrete car parks but also general concrete structures as part of any ongoing maintenance. This will allow for periodic small packages of repairs, as well as budgeting for major works projects.

There are various concrete repair options for the defects listed above but if it is a substantial repair to be undertaken, we recommend a product is specified with an appropriate guarantee.


Concrete car park maintenance may not be top priority for leaseholders but it is vital that these are not forgotten about as part of the successful management of a property.

Concrete defects will get exponentially worse over time, which only leads to larger repair projects being required and therefore increased costs. This can also result in the closing of car park for periods of time whilst the remedial works are carried out.

At Hamilton Darcey we can assist in undertaking inspections of concrete car parks to identify defects and specify repairs before they become a major problem. We also regularly provide budget costs for concrete structure maintenance and repairs for inclusion within service charge budgets and have a wealth of experience in undertaking projects to satisfy the terms of the lease and leave the area safe and usable.