Under the supervision of mr. Frans Schop, IBS Consultants successfully carried out a Qv;10 airtightness test at the Dordthuis building in Dordrecht. The purpose of the test was to verify that the building envelope complies with the specified airtightness requirements and to identify any potential unwanted air leakage.

Building Quality Assurance

The execution of this test forms part of the building’s quality assurance process. To achieve the ENE 26 credit, Assurance of the Thermal Performance of the Building Envelope, J.P. van Eesteren B.V. (JPvE) is required to demonstrate that the façade construction complies with the specified requirements for thermal insulation and airtightness.

The relevant credits are awarded during the completion phase once both the airtightness test and the thermographic inspection have been successfully carried out. These assessments provide insight into the quality of the building envelope. They verify that the thermal insulation has been installed correctly, confirm the absence of any undesirable thermal anomalies, and assess whether the achieved level of airtightness corresponds with the assumptions used in the building’s energy performance calculation.

Excellent Test Result

During the Qv;10 airtightness test, the building’s airtightness was assessed using a blower door test. This method enables any air leakage to be detected and located, allowing targeted corrective measures to be implemented where necessary.

For the office building, with a gross floor area (Ag) of 18,550 m², a qv;10 value of 0.046 dm³/s·m² was measured. This result comfortably exceeds the specified requirement and the reference value used in the BENG energy performance calculation of qv;10;lea;ref ≤ 0.20 dm³/s per m² of usable floor area.

Building Quality Assurance in Practice

Good airtightness contributes to an energy-efficient building, a comfortable indoor environment, and the optimal performance of building services. By carrying out independent testing, the quality of the completed building envelope can be objectively demonstrated.

With this successful Qv;10 airtightness test, IBS Consultants makes an important contribution to the objective verification of construction quality and supports its clients in delivering sustainable, energy-efficient, and future-proof buildings.

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For technical questions, please contact us at +31 (0)78 – 62 50 920 or via info@ibsconsultants.nl.