AiroTech is an accredited member of Elmhurst Energy a government authorised competent persons scheme.
We can test buildings from low energy Passive Houses using our smallest Retrotec 300 duct tester to large commercial properties requiring multi-fan air tightness testing.
Air Testing
Air tightness testing, also known as air leakage testing or air permeability testing , is a procedure performed to assess the air tightness of a building. In the UK, its is a mandatory requirement for new buildings both residential and commercial, as part of the building regulations. An air test is a quality check with the primary goal to ensure that buildings are constructed to meet energy efficiency standards and reduce heat loss through unwanted air leakages.
| Regulations | Air testing in the UK of simple(domestic) and non-simple buildings(commercial) buildings is based on ISO 9972 2015 methodology CIBSE TM23 contained within the building regulations Section 6(Scotland) and document L (England) |
| Testing procedure | Air tightness testing involves sealing all external openings of a building, including mechanical extractor vents, mechanical ventilation systems etc.. and closing external windows and doors. A blower door test fan is installed in an external doorway/window and the building is depressurised and/or pressurised to measure the amount of air leakage. |
| Target values | Building regulations specify target air tightness values that must be met for different buildings. These values are measured against the building envelope area expressed q50 value (m3/h.m2) in the UK and n50 (ACH) building volume in Europe and low energy buildings such as Passive Houses(Passivhaus) expressed at a pressure difference of 50 pascals(pa). |
| Test Certificates | Upon successful completion of an air test clients receive a verbal air tightness result on the day followed shortly by an ‘air permeability certificate’ which is documentary evidence that compliance with the building regulations has been met. |
| Importance | Achieving a good air tightness result can lead to various benefits such as reduced energy consumption, lower heating and cooling costs, improved indoor air quality and increased comfort for the occupants. Failure to meet the required air tightness standards can result in penalties and may require remedial works to be carried out on the building. |
Air Testing
Air tightness testing, also known as air leakage testing or air permeability testing , is a procedure performed to assess the air tightness if a building. In the UK, its is a mandatory requirement for new buildings both residential and commercial, as part of the building regulations. An air test is a quality check with the primary goal to ensure that buildings are constructed to meet energy efficiency standards and reduce heat loss through unwanted air leakages.
Regulations
Air testing in the UK of simple(domestic) and non-simple buildings(commercial) buildings is based on ISO 9972 2015 methodology CIBSE TM23 contained within the building regulations Section 6(Scotland) and document L (England)
Testing procedure
Air tightness testing involves sealing all external openings of a building, including mechanical extractor vents, mechanical ventilation systems etc.. and closing external windows and doors. A blower door test fan is installed in an external doorway/window and the building is depressurised and/or pressurised to measure the amount of air leakage.
Target values
Building regulations specify target air tightness values that must be met for different buildings. These values are measured against the building envelope area expressed q50 value (m3/h.m2) in the UK and n50 (ACH) building volume in Europe and low energy buildings such as Passive Houses(Passivhaus) expressed at a pressure difference of 50 pascals(pa).
Test Certificates
Upon successful completion of an air test clients receive a verbal air tightness result on the day followed shortly by an ‘air permeability certificate’ which is documentary evidence that compliance with the building regulations has been met.
Importance
Achieving a good air tightness result can lead to various benefits such as reduced energy consumption, lower heating and cooling costs, improved indoor air quality and increased comfort for the occupants. Failure to meet the required air tightness standards can result in penalties and may require remedial works to be carried out on the building.
Air Testing – Commercial
From small industrial units requiring only one test fan to large commercial premises requiring multiple test fans Airotech can provide the suitably qualified level 2 test engineers and calibrated test equipment to support all of our client’s air testing requirements.
If you are looking for Commercial Air Testing please contact us. We aim to reply to your enquiry within 24 hours.
Air Testing – New Build Residential
From low energy Passive houses(Passivhaus) requiring only a small duct tester to larger houses requiring larger volume fans Airotech can provide the suitably qualified level 1 test engineers and calibrated test equipment to support all of our client’s air testing requirements.
If you are looking for Residential Air Testing for New Build Homes, please contact us. We aim to reply to your enquiry within 24 hours.
Air Testing – Existing Homes
Air testing existing houses can ascertain whether energy is lost through holes and cracks in the thermal envelope.
Increasingly homeowners, housing associations and landlords want to ascertain the air tightness of their houses/properties as part of a wider refurbishment or retrofit strategy. By carrying out an air tightness test before and after any upgrade works ensures a quality check on how well the builders have reduced heat losses through sealing holes/cracks in the building fabric to make the building more energy efficient.
The results of these air tightness tests can be incorporated into the energy calculations to improve the energy performance or EPC(energy performance certificate) rating of the property which not only make it more comfortable to live in but also make it more attractive for future buyers or tenants.
If you are looking for Residential Air Testing for Existing Homes, please contact us. We aim to reply to your enquiry within 24 hours.
Air Testing – Low energy Passive House (Passivhaus)
Low air leakage is crucial for achieving the high energy efficiency standards of Passive houses. Conducting thorough air testing ensures that the building meets the stringent requirements, helping create an environment with minimal heat loss and optimal energy performance.
Passive House certification and standards
To meet low energy Passive house(Passivhaus) air test criteria for certification require not only proficient skills set but also specialist air test equipment. AiroTech have trained in house Passive house designers and Retrotec 300 Ductester systems to help our clients achieve the N50 = 0.6 air changes per hour – the passive house air test certification requirement. We would recommend to clients once they have installed the air tightness layer within their construction to carry out an intermediate air test to check its integrity.
If you are looking for Air Testing for Low energy Passive House (Passivhaus), please contact us. We aim to reply to your enquiry within 24 hours.
Preparing for an Air Tightness Test
To prepare the building for an Air Tightness Test please ensure the attached ‘Building preparation pre-test Checklist’ is completed, signed and returned to AiroTech. If you have any queries please feel free to contact us.
Frequently Asked Questions
Air leakage is the uncontrolled flow of air through a buildings envelope (roof, floor slab, external walls, windows, and external doors), either into a building (infiltration) or out of a building (exfiltration). This can be caused by various reasons including structural damage, poor quality workmanship, weather, inadequate design and detailing, deterioration of materials, etc.
Gaps and cracks in the building fabric are often difficult to detect simply by visual inspection. Air leakage paths through the building fabric are not uniform whereby cracks and gaps are often obscured by internal building finishes or external cladding. The only satisfactory way to show that the building fabric is reasonably airtight is to measure Air Permeability of the building fabric as a whole by performing an air tightness test.
Uncontrolled air movement within a building creates:
We assist our clients by quickly identifying areas of air leakage using either an artificial smoke generator and/or by using Infrared Thermography.
Areas of air leakage can be repaired or resealed and another air tightness test performed to prove the integrity of the repair/s. Please contact AiroTech.
‘Air tightness testing’ or ‘air leakage testing’ is a non-intrusive procedure to measure the amount of uncontrolled air leaking through the envelope or fabric of a building.
To measure the air permeability of a building, either in an existing one or a newly constructed one, a calibrated blower test fan, together with an air tight sealed door frame, are installed into the external envelope of the building. The fan is used to pressurise and/or depressurise the air in the building creating a pressure differential. The amount of air volume going out or into the building can be measured against this pressure differential giving the air permeability of the building.
The air leakage is measured in metres cubed per hour, in or out of the building, per square metre of building envelope at a reference pressure difference of 50 Pascals between the inside and outside of the building. Air Permeability Q50 = ..m3/(hr.m2) @ 50 Pa.
To ensure consistency of results the following equipment is required to be re-calibrated on an annual basis:
- Blower Door fan
- Manometer
- Thermometer
- Barometer
Many new constructions built today not only meet their target permeability figure but often exceed it i.e. lower permeability number. This leads to poor indoor air quality leading to moisture and mould propagation resulting in potentially respiratory problems for its occupants. This often means that a change in ventilation strategy has to be adopted at the end of the construction phase of a project leading to delays and additional costs to the developer/builder. By engaging with AiroTech early our clients would be recommended to carry out an intermediate air tightness test, after installing the air tight barrier and prior to completing the dry-lining on new building construction – please refer to client checklist.
Air tests are typically required once a building has been constructed (Residential or Commercial). The results of the air tightness test is fed into Standard Assessment Procedure (SAP) and Simplified Building Energy Model (SBEM) Calculations required for Building Control/Verifier (Scotland) sign off. Doing this satisifies the requirements of Part L of building regulations (and other regional variants).
- Scotland Technical handbook Section 6- 2015
- England and Wales – Part L 2013,
- Northern Ireland – Technical Booklet F 2012
- Isle of Man Building Regulations 2014
The Scottish Building Regulations Technical handbook para 6.2.5 (2019) sets out the guidelines for Air Testing domestic dwellings in Scotland. Testing should be performed in accordance with BS EN 13829: 2001 – ‘Thermal performance of buildings – determination of air permeability of buildings – fan pressurization method’.
For practical guidance procedure ATTMA TS L1 ‘Measuring Air Permeability in Envelopes of Dwellings (2016) is followed https://www.gov.scot/publications/building-standards-technical-handbook-2019-domestic-buildings/
A full list of Technical Standards used for Air Tightness Testing in the UK can be found here.
Air leakage/tightness can also be expressed as ACH or N50. This is the volume of air passing through a fan per hour in m3 to create an imposed pressure differential of 50 pascals divided by the volume of the building. ACH is the number of times the entire volume of air is replaced within the building in 1 hour at 50 pascals pressure.
ACH or N50 or ACH50 or ach-1 = m3/hr @ 50 pascals
Expressed at Q50 this is the volume of air passing through the blower fan per hour to create an imposed pressure differential of 50 pascals. It is then divided by the envelop area m2 of the building.
Air permeability Q50 = ..m3/(hr.m2) @ 50 Pa
The higher the number the more air can leak out of a building and visa a versa.
To perform Air Testing in Scotland and the UK, Air Testers must be members of one of two government national recognised registered competent schemes:
- IATS – Independent Air Testing Scheme
- ATTMA – Air Tightness Testing and Measurement Association
Air testers have to attend a recognised Air testing course and pass both practical/written exams laid out by the National Occupational Standards (NOS)
before registration.
AiroTech are members of the IATS
Pre-construction: Designers, Specifiers, SAP Assessors, SBEM commercial energy assessors, Consultants, etc..
During construction: Architects, Engineers, Project Managers, Builders, Sub-contractors, Sealers (fire stop and envelope), Building Control Officers, etc.
Post Construction: Owner, Occupiers, Maintenance Staff, Caretaker, Governments etc.
The energy we use to heat our homes primarily comes from the burning of fossil fuels (gas and coal). If we reduce the amount of energy required to heat our homes, by reducing heat loses via uncontrolled air leakages, we reduce the amount fossil fuels and CO2 emissions into the atmosphere.
Air Testing Projects
Air Tightness Test, Arbroath
Air Tightness Test, Arbroath Costa Coffee
ATT at Ice Bowl in Dumfries
Air Tightness Testing at Ice Bowl in Dumfries
Office Complex in Edinburgh
Air Tightness Testing 8 story Office Complex
Sheltered housing, Edinburgh
ATT and internal/external IR in Edinburgh
Renovation of 1926 bungalow
Renovation of bungalow to two storey house
New build semi-detached house
Air tightness test and infrared building survey
ATT & IR at Loch Fyne, Scotland
Air tightness test and infrared building survey
ATT & IR at Jacobs Well, Surrey
Air tightness test and infrared building survey
Contact Us
If you require Air Testing for your Commercial or Residential property, please contact AiroTech for a quotation or to discuss your requirements.