Air and water tightness

Construction stakeholders are legally liable for defects that affect a building’s air and water tightness, alongside other critical performance elements. These fall under the scope of the ten-year civil liability framework.

To mitigate this risk, many project owners choose to take out decennial insurance, which requires validation by an independent inspection body—such as SECO.

SECO is recognized by all Belgian insurers for its expertise in technical control related to airtightness, watertightness, structural stability, finishing works, building systems, and fire safety.

Through inspections and audits across every stage of a building’s life—design, construction, renovation, and operation—SECO’s engineers help ensure that air and water barriers are properly specified, installed, and maintained. This includes checking detailing at junctions, verifying pressure tests and continuity of membranes, and assessing long-term performance during the operational phase.

Beyond insurance compliance, early and ongoing attention to airtightness and watertightness enhances occupant comfort, energy performance, and the durability of the building envelope. Technical inspection in this area is a critical tool for quality assurance, especially in high-performance or passive buildings.