Air Tightness

Draught-proofing Air Test

Building Compliance Testing Limited can provide you with a fast and cost effective ATTMA Accredited Air Tightness Testing across Mainland UK, in accordance with BS EN ISO 9972:2015 and CIBSE TM23.

green tick BCTAir Tightness Testing

Air Tightness Testing or air leakage testing, is a mandatory procedure under Part L of the Building Regulations, forming an integral part of the new building’s overall energy performance assessment; it quantifies air leakage in terms of cubic meters per hour per square meter at 50 Pascals (or 4Pa for Pulse Testing), which, if excessive, can result from gaps and cracks in the building envelope, causing energy loss and potential carbon dioxide emissions. The test is conducted using a UKAS calibrated blower door system, typically taking between twenty minutes to a few hours, with Building Compliance Testing offering comprehensive services including design reviews, site inspections, and smoke diagnostics to support various building requirements.

Draughtproofing is important for improving energy efficiency, reducing heating and cooling costs, enhancing occupant comfort, and minimizing the environmental impact of a building by sealing gaps and air leaks. Blower door air tests are instrumental in identifying and quantifying these leaks, allowing for targeted draughtproofing measures to be implemented, ultimately leading to a more efficient and environmentally friendly building.


Other Services

– Part L Compliance

– Smoke Shaft Testing for Automatic Opening Ventilation (AOV)

– Room Integrity Testing

– Smoke Testing

– Multi-fan Commercial Testing

– Existing Buildings Testing

– Air Tightness Design Reviews

– Plenum and Raised Access Testing (RAF) to BG65 Standards

– Passivhaus Testing

– Air Sealing in preparation for Air Tightness Testing


Air leakage testing, a requirement under Part L of the Building Regulations, assesses a building’s energy performance by measuring the volume of air escaping per hour per square meter at a specific pressure level (usually 50 Pascals). This test helps identify gaps and cracks in the building envelope, through which conditioned air can escape, leading to increased heating or cooling costs and potential carbon dioxide emissions. Conducted using a calibrated blower door system, the test takes approximately twenty minutes to a few hours and involves a fan, manometer, and software to determine results. Building Compliance Testing offers a comprehensive service, including design reviews, site inspections, and training, alongside other services such as smoke testing, air tightness design reviews, and Passivhaus testing, to ensure compliance and energy efficiency in various building types.


Frequently Asked Questions

What is required for an Air Tightness Test?
  • Floor Plans and Section Drawings
  • Site Address and Contact
  • A copy of the Design-stage SAP report for dwellings
  • A copy of the Design-stage BRUKL report for buildings other than dwellings i.e retail units
When do I know when I am ready for an Air Tightness Test?
  • We will carry out the air tightness test once the unit is past the second fix stage and the following
    elements within the unit are completed:
  • All walls are finished, including cladding, windows and doors.
  • Skirting boards are fitted and sealed around
  • Sockets and lights are fitted and completed, in some cases caulked around (mention potty pads)
  • All plumbing work is completed and gaps or holes around the service pipes are sealed.
  • Leakage around the door frame, threshold and window boards are sealed.
What am I allowed to temporarily seal for an Air Tightness Test?
Background trickle ventialtors, passive ventilation systems and any permanently designed uncontrolled natural ventilation (such as a chimney flue). Mechanical ventilation and air conditioning systems should be turned off and isolated.

We’re friendly and knowledgeable bunch so why not get in touch for a chat. You can always contact Building Compliance Testing with any questions through phone, email or our online chat service.

Don’t worry, we don’t charge for advice given over the phone, so why not ask for a free quote?

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