Ventilation & Airthightness

With our strong knowledge of European standards and regulation we help you to develop new products and methods or to consolidate your research activities in full confidentiality.

PLEIAQ is involved in multiple-partners research projects in Europe and in France such as PROMEVENT (residential and non-residential), Durabilit'air and EPBD 19a .

We are active in AIVC, a project of the International Energy Agency on ventilation and air infiltration in buildings that brings together international experts. We disseminate research products, for instance through the European and international platforms TightVent (on building and ductwork airtightness).

During the COVID epidemy Valerie Leprince was an active member of Ashrae Epidemic Task Force in the Residential Team and has contributed to the official ASHRAE recommendations. She was also involved in the AIVC-COVID working group for which she has set a webinar and contributed to the FAQ.

We write papers and scientific reports upon request of our clients or for our own.

Research projects for the industry

Flowrate through windows

A comparative analysis of window airing models proposed in prEN 16798-7 has been performed and the influence of internal resistances has been taken into account. The ouput of the study are the equations implemented in the EPBD standard EN 16798-7.

Four conference and journal papers have been published:

Impact of ductwork airightness on fan energy use

For this project a method has been developed to calculate conservative estimates of fan energy use impacts of duct airtightness improvements. This method has been implemented in an Excel tool that has been tested on a laboratory replication of a multi-family building ductwork.

Two articles have been published on this project:

Ductwork airtightness in single houses

In this study the impact of ductwork leakages on the fan energy use of central mechanical ventilation units with heat recovery used in typical houses has been calculated. In addition, the impact on the sound pressure in dwellings has been investigated.

An article has been published at the AIVC 2019 conference :

Pressure drop calculation tool

Various solutions are under development to replace boilers connected tocentralised ventilation systems by more efficient condensing boilers.

However, these solutions imply to have new tubes (to extract the smoke) running inside the existing ventilation ductwork. These new tubes induce changes in the pressure drop of the ventilation air flowrate.


  • been involved in the definition of test cases to be tested through CFD simulation to establish new pressure drop equations

  • been involved in the elaboration of the equations

  • created the calculation tool to estimate pressure drop in the ductwork

French national research project (founded by ADEME)


PROMEVENT, a project of the French programme « Towards responsible buildings at horizon 2020 ». This project aimed at improving the reliability of inspection's protocol for ventilation systems in residential buildings (including flowrate measurement at air terminal devices). PLEIAQ has mainly been involved in the literature review and on the reliability of the ductwork airtightness test.


DURABILIT’AIR aims at improving knowledge on envelope airtightness durability. The 4 major objectives are:

Promevent tertiaire

Promevent Tertiaire has the same objective as Promevent but for non-residential buildings. PLEIAQ is in charge of

  • Task 1.1: Review of existing systems in non-residential systems: PLEIAQ_Report_2018_05

  • Task 4: Impact of non-conformities on energy use and indoor air quality with three published report:

    • Detailed methodology for the estimation of non-conformities' impact (report available soon)

    • Case studies on three inspected buildings (2 schools and 1 office building) (report available soon)

    • Practical summaries of the non-conformities' impact (report available soon)

The reliability of the ductwork airtightness test has also been further studied:

Other projects

Impact of wind on building airtightness test

PLEIAQ is involved in the AIVC working group on the impact of wind and stack effect on the result of building airtightness tests.

A Ventilation Information Paper was written for INIVE , gathering published knowledge on the quantification of the wind impact on airtightness tests results, determining what further research is needed, and giving guidance to minimize this impact:

Blower door fan deviation over the years

PLEIAQ has been working through the analysis of fan calibration certificates on the deviation of blower door fans over years.

Ductwork airtightness

PLEIAQ has written a Ventilation Information Paper for INIVE , providing a literature review of the work performed in the field of ductwork airtightness.

High-rise buildings airtightness measurements

High-rise buildings are particularly difficult to test for air permeability measurents through pressurisation because of the stack effect.

PLEIAQ has published an AIVC article on this subject in 2021.