BADA

This paper introduces an experimental study of enclosure airtightness testing of an outdoor chamber using both the pulse technique and the blower door method.  This investigation is a 2nd stage comparison study following the previous testing of a house-sized chamber in a sheltered environment.  The outdoor chamber in this study has dimensions, approximately half that of a standard 20ft long shipping container.  Multiple openings were installed into the chamber’s envelope to provide a leakage level and characteristics similar to an average UK house.

Since the 1970s, many authors have discussed the impact of poor airtightness on building energy use, indoor air quality, building damage, or noise transmission (Carrié and Rosenthal, 2008) (Tamura, 1975) (Sherman and Chan, 2006) (Orr and Figley, 1980). Nowadays, because poor airtightness affects significantly the energy performance of buildings, and even more significantly with low-energy targets, many countries include requirements for building airtightness in their national regulations or energy-efficiency programs.

Aeroseal technology utilizes air laden with fine aerosol particles (2-20 μm) to pressurize a duct system, resulting in deposition of those particles at the leaks within that duct system. By reducing leakages of duct systems by 90% in average Aeroseal sealing technology allows reducing leakages to a standard better as air tightness class D or ATC 1 for a complete system. Aeroseal technology can be applied in new constructions as well as in existing systems to improve energy efficiency, cleanliness of ventilation systems, IAQ and comfort.

The implementation of the Energy Performance of Buildings Directive 2010/31/EU recast puts increasing pressure to achieve better building and ductwork airtightness.  

In this context, Eurovent Certita Certification decided to establish a new certification programme for Ventilation Ductwork Systems, opening a new chapter in the history of the Eurovent Certified Performance (ECP) certification mark, which concerned only products, not systems, until then.  

This paper summarizes the most recent results of the French database of ductwork airtightness. This database was created in 2016. It is fed through measurements performed by qualified testers according to a national scheme regarding ductwork. Measurements are mainly performed in building applying for the Effinergie + label which requires class A for ductwork airtightness. Therefore, results discuss in this paper only apply to the buildings of the database and cannot be generalized to all new buildings in France.

A ductwork system that has limited air leakage, within defined limits, will ensure that the design characteristics of the VAC system are sustained. It will also ensure that energy and operational costs are maintained at optimal levels. 

Does the UK have any requirements regarding ventilation ductwork airtightness and how does the UK assess the installed performance of ducted mechanical ventilation systems? 

Duct leakage airflow in existing ductwork can reach values of over 20% of the design air handling unit (AHU) airflow, undermining efficiency and effectiveness of HVAC systems. We have measured, in an existing building where ductwork was installed 20 years before, with no special care on duct leakage and tight building construction schedules, operational duct leakage rates between 10% and 40% of the AHUs airflows. 

One of the main factors influencing building airtightness is the construction typology. As building environmental performance requirements raise so does the prevalence of less conventional envelope construction systems as modular structural insulated panels (SIPs) buildings.  

The increasing weight of building leakages energy impact on the overall energy performance of low-energy buildings led to a better understanding of the actual airtightness performance of buildings. However, low expertise is available today on the durability of airtightness products in mid- and long-term scales. The French ongoing research project “Durabilit'air” (2016-2019) aims at improving our knowledge on the variation of buildings airtightness through onsite measurement and accelerated ageing in laboratory controlled conditions.

In this study, durability of building airtightness was assessed by means of repeated airtightness testing of the studied houses. This approach generally involves the following issues which complicate the comparison of the test results: