Rob van den Boetzelaer of the building consultancy Qkeur answers our questions on construction and explains the most common structural defects.
Concrete rot
From 1965 to 1981, single-family homes were built with prefabricated concrete ground floors. Mostly of the Kwaaitaal or Manta make. Adding calcium chlorides made the concrete dry faster; however, it later turned out that the calcium chlorides cause the steel reinforcement in the concrete to rust. This then leads to concrete damage, or concrete rot.
Fortunately, these floors were used only to a limited extent in the city of Utrecht. Kwaaitaal and Manta floors were used locally in Overvecht, Tolsteeg and on parts of the Mijdrechtstraat. They were used more in the villages around Utrecht. Many neighbourhoods in Nieuwegein, Maarssen, IJsselstein, Vianen, Zeist, De Meern and Bilthoven.
Utrecht also has only a few neighbourhoods with homes from the years 1965 to 1981. It's always smart to have a building surveyor take a look at the concrete floor.
Other points to watch in homes from the 1960–1980 building period
- Condition of the tiled roof and flat roofs
- Condition of chimneys
- Pointing turning to sand (crumbling mortar joints)
- Vermin
- Poor sound insulation
- Concrete rot
- Asbestos
- Thermal bridges (in combination with double glazing)
- Asbestos or vitrified clay (gres) sewer pipes
Building surveyor
Rob completed his building engineering training at the MTS (technical secondary school). He has been surveying houses for more than 25 years, has worked for housing associations and the municipality, worked at an engineering firm in asbestos removal and asbestos surveys, and has supervised many construction projects. Rob has already surveyed many houses in Utrecht. Q-keur is a building consultancy specialising in building surveys, multi-year maintenance budgets and building advice. Q-keur works mainly in and around Utrecht.
