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Air Tightness Testing

Air Tightness Testing

Elevate your building’s energy efficiency through Thermalume’s Air Tightness Testing – a pivotal solution for mitigating heat loss, diminishing carbon emission, and ensuring stringent compliance with prevailing regualtions.

Our seasoned technicians deploy state-of-the-art blower door systems, meticulously identifying and rectifying uncontrolled air leaks, establishing hermetically sealed structures that align seamlessly with the exacting standards of Part L in Building Regulations.

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    Reasons to choose Thermalume

    • Proficiency: With an extensive track record in the industry, Thermalume brings unparalleled proficiency to every project. Thermalume offers, simplified booking system for easy date and time slot selection.
    • Compliance Guarantee: Our air permeability testing strictly adheres to prevailing building regulations, providing an assurance that your construction surpasses mandated standards. We are  ATTMA registered, ensuring industry compliance, furthermore, we exclusively employ qualified and experienced air testers and utilise thermal imaging or smoke for diagnostic tests on major leaks.
    • Tailored Precision :We tailor our methodologies for each building, ensuring meticulousness and efficacy in pinpointing and addressing air leaks. We are authorised by ATTMA for envelope area and volume calculations, we offer expert advice provided to avoid common pitfalls and ensure first-time test success and conduct pre-tests at different build stages to identify potential issues.
    • Nationwide Reach: While headquartered in Canterbury, our services extend comprehensively to Chelmsford, Colchester, Maidstone, Milton Keynes, Oxford, Reading, Swindon, and Watford.
    • Swift Results: Our streamlined testing procedures yield prompt results, enabling immediate action toward cultivating a more energy-efficient and ecologically sound building, furthermore, we guarantee lodgement certificates within 48 hours.

    Depressurised thermal survey

    As AATMA-registered testers, we can check if your building meets Part L regulations and provide air permeability certificates for your Building Control Body. This test is crucial for compliance and can be one of the final steps before your property is approved. We’ve noticed more clients asking us to test existing buildings to see how much air they’re losing. This data is vital for planning renovations or deciding if your building is suitable for underfloor heating or air source heat pumps. If your building isn’t energy-efficient due to poor insulation, any savings from new systems could be wasted.
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    What is Air Tightness Testing?

    Air Tightness Testing, also known as Air Permeability, Leakage, or Pressure Testing, gauges the volume of air escaping a building’s envelope. This procedure, essential for energy efficiency and cost-effectiveness, identifies and mitigates drafts. Striking a balance between air tightness and ventilation is crucial to minimise heat loss, curb C02 emissions, aligning with the objectives of ‘Part L’ in new building regulations.

    Importance of air tightness testing

    Over a decade ago, air tightness testing became a crucial addition to Part L of Building Regulations due to its revelation that uncontrolled air leakage significantly contributes to heat loss. Despite builders’ efforts to construct tightly sealed structures, visual inspections alone cannot gauge success. Air tightness testing ensures effective insulation, preventing the nullification of performance gains from design and modern materials.

    How do air leakage tests work?

    In air tightness testing, an air leakage test measures the extent of uncontrolled air movement through a building’s envelope. The process typically involves pressurising or depressurising the building using a blower door system. The technician instals a powerful fan in an exterior door, adjusts the pressure inside, and then measures the airflow required to maintain that pressure. This helps identify areas of potential leakage, enabling corrective measures to enhance energy efficiency and reduce heat loss.

    A door being blocked for an air test by Thermalume

    Blower Door Test

    What are the air permeability testing building regulations?

    The current air tightness regulations fall under Part L (Conservation of Fuel and Power) of the Building Regulations, applying to new constructions in England and Wales and certain renovations.

    These regulations stipulate air permeability requirements, measured in cubic metres of air leakage per hour per square metre at a reference pressure of 50 Pascals. For new dwellings, the maximum allowable air permeability is 10 m³/h.m². The air permeability test, conducted using a blower door, assesses the building envelope for air leaks.

    Regulations may evolve as the UK government aims to enhance energy efficiency and reduce carbon emissions. Local authorities might have additional or stricter requirements. Notably, in 2023, Scotland implemented new standards mandating Passivhaus construction for all new housing, prioritising carbon-friendly practices.

    When do you need to carry the air test out?

    New Constructions

    Air tests are mandatory for newly built structures to ensure compliance with air tightness regulations.

    Renovations and Extensions

    Certain renovations and extensions fall under the scope of air tightness testing regulations to assess and improve existing structures.

    Energy Efficiency Assessments

    Air tests are conducted as part of energy efficiency assessments to identify and rectify air leaks, reducing heat loss and improving overall energy performance.

    Regulatory Compliance

    Adherence to building regulations requires air testing to meet specified air permeability standards and contribute to sustainable construction practices.

    Get in Touch

    If you have any questions or would like to book one of our services, please contact us

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    1. What locations does Thermalume cover?
    We serve at Canterbury, Chelmsford, Colchester, Maidstone, Milton Keynes, Oxford, Reading, Swindon and Watford.

    2. Why is air tightness testing necessary for new constructions and renovations?
    Air tightness testing ensures compliance with building regulations, minimising uncontrolled air leakage, reducing heat loss, and enhancing energy efficiency.

    3. When should I consider conducting an air permeability test on my building?
    An air permeability test is recommended for new constructions, certain renovations, and extensions to assess and address any potential air leaks, contributing to better energy performance and regulatory compliance.


    Choose Thermalume today!

    Ready to enhance your building’s energy efficiency and compliance? Schedule an Air Tightness Test today with Thermalume. Ensure your construction meets regulatory standards, minimises heat loss, and promotes sustainability. Contact us to book your test and take a significant step towards a more energy-efficient and environmentally friendly building.