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Air Permeability Test

We provide Air Permeability Testing for every type of building!

Who Needs Air Permeability Testing?

Air permeability testing, also known as air tightness testing or blower door testing, was included in Part L of the building regulations in 2010, as part of the government’s scheme to conserve fuel and power. A building with a high amount of air leakages is in danger of a vast increase in the rate which heat is lost from the property; on the other hand if there isn’t enough ventilation the air becomes stagnant increasing the chances of mould and damp, which can be potentially dangerous to occupants.

Approved document F defines airtightness as a descriptive term for how resistant a building’s envelope is to air escaping or entering the property, whilst all other ventilation is closed (ie windows, doors, vent systems). All new build commercial properties over 500m² and many new build or conversion residential properties are required to be tested to determine their air-tightness.

The size of the residential development will alter the amount of air permeability tests that you require, part L1a regulations state that developments with less than 4 properties require two tests of each dwelling type, between 5-40 require three tests of each dwelling type, and 41+ need at least 10% of each dwelling type tested, unless the first 5 tests successfully attain the required air permeability, in which case the testing frequency can be reduced to 8%. For individual dwellings an air permeability test is not a legal requirement, but may be required to achieve a pass on the SAP Compliance Report.

What does Air Permeability Testing involve?

Following the method for testing required by building regulations as set out in ATTMA TSL1 (residential) and ATTMA TSL2 (commercial), all doors, windows and vents are closed or sealed, any flames in fireplaces will also have to be put out. Next a piece of equipment that comprises of a door holding a large fan is mounted inside the frame of an external door (generally the front door is used, providing it is “standard" size), when the fan is turned on it depressurises the building by extracting air from the property. The air permeability of the property is calculated using the difference between the internal and external pressure of the building envelope.

All residential new builds and conversions need to achieve a minimum level of air permeability of (10m³/(h.m²)), this information is included in your SAP calcs/EPC for building control.

Commercial properties require a minimum minimum standard of ≤(10m³/(h.m-²)) at a pressure of 50 pascals.

What do I get?

Prior to the appointment, we can provide you with a clear, easy to understand checklist to help you prepare your property for the survey, ensuring you achieve the best result possible. After the appointment, providing your property has passed, you will receive an iATS accredited pass test certificate, stating all relevant information such as the measured air permeability, envelope area of the building, assessors name and competence level, etc.

For residential properties, if the air test fails, our assessor will inform the site contact and discuss the result, potential problems that could be causing the failure and what could be done to correct these (for example, this could be as simple as fitting draft excluders to a loft hatch).

For commercial properties, if the building fails we can offer diagnostic testing services such as smoke tests and thermographic surveys to identify why the property has failed.

Who will carry out the survey

Easy EPC has a highly skilled, fully qualified and fully insured team of air permeability testing engineers, who are all iATS certified. We have engineers all over the UK, all of whom can carry out up to 15 air tightness tests in one working day, meaning that if you have a large development to test, we can efficiently help you keep in time with your deadlines. We also offer discounts for numerous bookings for the same appointment, contact us today to see if you are eligible for bulk discount.

What else may I need

Building control will also request SAP calcs/EPC for your new build or conversion, we offer both “as designed" and “as built" SAP services, meaning that we can help at all stages of your build or conversion!

Part E of the building regulations require that your new build or conversion property conforms to it’s Sound Insulation Testing limitations.

Building control may also require you to carry out Water Use Calculations to confirm that your property is compliant with that max water usage per person per day, as set out in part G.

How do I book?

To get a quote for a air permeability test for your property simply give us a call on 0800 170 1201, or alternatively fill in our contact form. The basic information we need to be able to provide you with a price for the survey is:

  • Full Address/Postcode
  • Clear floor plans, sections and elevations

Once we have provided you with a quote, if you wish to go ahead and book we will also need invoicing details and contact details for whoever will be meeting us on site. We don't charge up-front, but will invoice you for the work on completion, and release the air permeability certificate to you upon receipt of payment. Our pricing includes use of equipment and travel, so the price we quote you is the total price you will pay.

After you have booked with us we will contact you or if you prefer an alternative site contact to arrange an appointment. Once we have visited site the report should be ready the next working day, at which point we will contact you to let you know its ready and provide you with an invoice. On payment of the invoice we will email your Air Permeability Pass Certificate.

Our prices start from £199.95 + VAT, dependant on size and location of the property. Use this online booking tool to quickly get a quote for your Sound Test.

You may also be interested in:

Sound Insulation Testing
Water Use Calculations
SAP Calcs for Extensions
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EPC Certification