Under pressure
Energy efficiency is high on the list of must-haves in any new build. Does that mean it needs to be airtight? Baden Brown from 5merchants, the specialist distributor of Passivhaus components, explains.
Blower door testing is an essential procedure used in the construction industry to assess the airtightness of buildings. It involves using a powerful fan installed in an exterior doorway, creating a pressure difference between the inside and outside of the building. By measuring the airflow required to maintain this pressure difference, professionals can determine the level of air leakage in the building envelope.
Blower door testing holds significant importance for several reasons:
• Energy Efficiency: Airtightness plays a crucial role in the energy performance of buildings. Inefficient buildings with excessive air leakage require more energy for heating and cooling, leading to higher energy bills and increased carbon emissions. Blower door testing helps identify areas of air leakage, allowing for targeted sealing and implementing energy-efficient measures.
• Comfort and Indoor Air Quality: Air leakage can lead to drafts, cold spots, and moisture-related issues, affecting occupant comfort and wellbeing. By conducting blower door tests, builders and homeowners can pinpoint areas where drafts and cold air infiltrate, enabling them to enhance insulation and seal gaps effectively. Improved airtightness contributes to better indoor air quality by reducing the ingress of pollutants, allergens, and outdoor contaminants.
• Building Code Compliance: While the New Zealand Building Code (NZBC) sadly has no specific airtightness targets, the performance of insulation and effectiveness of weather tightness for example are quantifiable with a blower door test. Blower door testing effectively demonstrates compliance with these regulations which would otherwise not be identified with a visual inspection.
• Health and Moisture Control: Uncontrolled air leakage can lead to moisture intrusion, resulting in mould growth, structural damage and compromised indoor air quality. Blower door testing helps identify areas of potential moisture penetration and enables builders to address these issues proactively. Minimising air leakage can significantly reduce the risk of moisture-related problems and associated health concerns.
• Durability and Longevity: Airtightness is crucial for the long-term durability and longevity of buildings. Uncontrolled air movement can lead to the degradation of building materials and contribute to structural issues over time. By conducting blower door tests, potential weak points in the building envelope can be identified, allowing for appropriate remedial measures to ensure the building’s longevity and reduce maintenance costs.
Blower door testing is vital for promoting energy efficiency, improving occupant comfort, complying with building regulations, ensuring indoor air quality and enhancing the durability of buildings. Book a blower door test with us to start your journey to an energy-efficient home.
0800 434 287 | 5merchants.co.nz
