Air leakage can cause a significant amount of a building’s energy loss, highlighting the critical role that airtightness plays in the energy efficiency of new buildings. Ensuring a well-sealed building improves its energy performance, enhances occupant comfort, and reduces environmental impact.
This guide will explore and explain the process of new-build air testing, a crucial step in verifying the airtightness of newly constructed properties. We’ll examine what the test involves, why it’s necessary, and how it can benefit homeowners and builders in achieving high energy standards and meeting Building Regulations Part L.
Contact the team at Falcon Energy to learn more about our testing services and to book airtightness testing for your domestic or commercial property.
What is new-build air testing?
New-build air testing, also known as airtightness testing, air pressure testing, or air permeability testing, is a procedure used to measure how much air leaks out of or into a newly constructed building. It assesses the level of airtightness in a property, ensuring that the building envelope – walls, windows, doors, and other elements – is sealed effectively to minimise uncontrolled airflow.
Why is it necessary?
Airtightness testing is a mandatory requirement for new builds under Building Regulations Part L, which sets standards for the energy performance of new properties.
The regulations require buildings to meet specific airtightness levels to ensure they are energy-efficient and environmentally friendly. Without passing an air test, a new build cannot obtain a final completion certificate, making this an essential step in the construction process.
When to consider airtightness testing for new build developments
The importance of airtightness in new builds
Airtightness testing is essential to modern building design, particularly for new constructions. It influences not only a building’s energy performance but also the comfort and health of its occupants.
Energy conservation
Achieving high levels of airtightness is one of the most effective ways to reduce energy consumption and lower the carbon footprint of a building. By minimising unwanted air leakage, new builds require less energy for heating and cooling, which directly translates into:
- Lower energy demand: Efficient insulation and reduced heat loss mean less energy is needed to maintain comfortable indoor temperatures.
- Cost savings: Lower energy consumption reduces utility bills, making the building more economical to operate in the long term.
- Sustainability: Lower energy usage also means fewer carbon emissions, which contributes to environmental sustainability and helps meet global climate goals.
Impact on indoor air quality
Airtightness also plays a pivotal role in maintaining good indoor air quality and thermal comfort:
- Preventing draughts: A well-sealed building envelope prevents cold air from infiltrating and warm air from escaping, eliminating uncomfortable draughts and cold spots.
- Consistent temperatures: Airtightness helps maintain consistent indoor temperatures, reducing fluctuations that can cause discomfort.
- Improved ventilation control: With a controlled environment, mechanical ventilation systems can work more effectively to provide fresh air without being compromised by uncontrolled air leakage.
Compliance with regulations
As stated above, all new builds must comply with specific airtightness requirements set out in Building Regulations Part L. Meeting these standards is not only a legal obligation but also a marker of quality and efficiency:
- Meeting target levels: New builds are required to achieve a specific air permeability rate, usually no greater than 10 m³/(h·m²) at 50 Pascals of pressure. However, many high-performance buildings aim for much lower levels to optimise energy efficiency.
- Certification and approval: Passing an airtightness test is necessary to obtain the final completion certificate for a new build, which confirms that the property meets the required standards for energy performance.
Ensuring airtightness in new builds is not just about meeting regulatory requirements – it’s about building homes and commercial spaces that are comfortable, energy-efficient, and environmentally responsible.
How is an airtightness test conducted?
An airtightness test, typically performed using a blower door system, involves installing a large fan in an external doorway to measure a building’s air leakage rate. The fan either pressurises or depressurises the property, and sensors record the airflow and pressure differences. This data is used to calculate the building’s air permeability, which determines whether it meets the required standards for energy efficiency.
Gaps around windows and doors, service penetrations, and poorly sealed loft hatches are common areas where leaks are detected. Identifying and sealing these leak points is essential for improving energy efficiency, reducing heat loss, and achieving compliance.
Preparing for a new building airtightness test
Pre-test checklist
Before an airtightness test, all windows and doors should be correctly installed and sealed, and any gaps around service penetrations (such as pipes and cables) should be properly filled. Ventilation systems must be turned off, and internal doors should be left open.
It’s also important to seal any temporary openings, such as loft hatches or ductwork, to maintain accurate test conditions.
Avoid common mistakes
To prevent test failures, good building practices should be followed throughout construction.
This includes:
- properly sealing joints
- using airtight materials
- addressing potential leak points early on
Thorough planning and attention to detail during construction are key to achieving a successful airtightness test.
What happens if a new build fails an air test?
When a new build fails an air test, it indicates excessive air leakage, often due to poor sealing around windows and doors, gaps in insulation, or unsealed service penetrations. This failure means the building does not meet required airtightness standards, affecting energy efficiency and regulation compliance.
To address these issues, remedial actions include sealing gaps with appropriate materials, improving insulation, and ensuring all joints and penetrations are properly closed. Once repairs are made, a retest can be scheduled. The cost and requirements for retesting depend on the extent of the initial issues and the time needed to complete the fixes, but it’s essential to address all identified problems to ensure compliance and avoid additional expenses.
Benefits of passing airtightness testing
Passing airtightness testing is crucial for developers as it ensures new builds meet Building Regulations, avoiding project completion delays and potential penalties. It also demonstrates a commitment to high-quality construction, enhancing the developer’s reputation and increasing buyer confidence.
Energy-efficient properties with strong airtightness credentials are more marketable, offering reduced running costs and environmental benefits. This can lead to higher property values, quicker sales, and a competitive edge in the market, making them a valuable investment in long-term project success.
Why choose a professional for your airtightness testing?
- Accurate results
- Identification of potential problem areas
- Guidance on addressing issues effectively
- A smooth certification process
Hiring a professional for airtightness testing ensures accurate and reliable results, as they have the expertise, equipment, and knowledge to perform the test correctly. Professionals can identify and diagnose potential problem areas and provide guidance on how to address them effectively, which is crucial for passing the test and meeting regulatory requirements.
Additionally, working with a certified expert can save time and money by avoiding costly mistakes and re-tests. Their experience in handling complex builds and compliance documentation ensures a smooth certification process, giving you peace of mind and confidence in the quality and performance of your new build.
Book a new building airtightness test with Falcon Energy
Ensuring your new build passes an airtightness test is essential for meeting Building Regulations, optimising energy efficiency, and enhancing property value. Falcon Energy offers professional and reliable testing services to help you achieve compliance and deliver high-quality, energy-efficient properties.
Our certified experts use advanced equipment to provide accurate results and comprehensive support throughout the process. Don’t risk delays or costly re-tests – choose Falcon Energy for your airtightness testing needs.
Contact us today to schedule your airtightness test and ensure your new build meets the highest efficiency and performance standards.
New build airtightness testing FAQ
What is the target air permeability rate for new builds?
The target air permeability rate for new builds is typically no greater than 8 m³/(h·m²) at 50 Pascals. However, more energy-efficient buildings, such as those adhering to Passivhaus standards, aim for much lower rates, around 1 m³/(h·m²) or less.
How long does an air test take?
An air test usually takes 1 to 2 hours to complete, depending on the size and complexity of the building. This includes the time needed for setting up, testing, and analysing the results.
What happens during a retest?
If a building fails the initial test, a retest is conducted after remedial work is completed to improve airtightness. The process is similar to the initial test but focuses on verifying that the identified issues have been resolved. Retesting may involve additional costs and should be scheduled promptly to avoid project delays.