Around 160 participants attended the joint 36th AIVC – 5th TightVent – 3rd venticool conference held in Madrid, Spain September 23-24, 2015. The programme consisted of 3 parallel sessions with contributions from 27 countries and international organisations.

Over 120 presentations were given covering topics ranging from air infiltration through leaks in the building envelope and ductwork, ventilation in relation to IAQ and health, ventilative cooling and thermal comfort.

It has also been a major discussion place for on-going projects and initiatives such as the TightVent Europe and venticool (http://venticool.eu/) platforms, the Indoor Environmental Quality – Global Alliance (http://ieq-ga.net/), the QUALICHeCK project and platform, the IEA EBC annex 62 (http://venticool.eu/annex-62-home/), the IEA EBC annex 68 (http://www.iea-ebc.org/projects/project?AnnexID=68) and the Renew School project (http://www.renew-school.eu), based on presentations of results and perspectives as well as fruitful interactions with the audience.

The airtightness track of the conference consisted of 5 sessions with 23 presentations. Specific topical sessions dealing with airtightness included the following topics:

• Building airtightness testing: ground status from various countries
• Airtightness – Airflow measurements
• Solutions and future developments for airtight envelopes and ductwork in new and renovated buildings
• Air infiltration modelling
• Airflow and airtightness measurements

The article avalable here summarises the main trends and conclusions addressed during the presentations and discussions in the airtightness track of the conference.