What is Commercial Air Pressure Testing?

Commercial air pressure testing, also known as commercial air tightness testing, of non-domestic buildings is a requirement of Part L2A of the current Building Regulations. It is intended to prevent air leakage in buildings which is the uncontrolled flow of air through gaps and cracks in a building fabric, also known as infiltration or draughts.

Most new build non-domestic buildings will now require a commercial air pressure test, as will large extensions to existing buildings.

In the UK, the approved procedure for air pressure testing, or air tightness testing, commercial buildings is ATTMA TSL2, which is based on BS EN 13829:2001 ‘Thermal Performance of Buildings – Determination of Air Permeability of buildings – Fan pressurisation method’.

Part L2A of the Building Regulations requires that any building undergoing a commercial air pressure test, or commercial air tightness test, must achieve an air Permeability Result of less than or equal to 10m³/h/m² at a pressure differential of 50 pascals.

There are many benefits to an airtight building, such as:

• Lower heating costs
• Lower carbon emissions
• Smaller requirement for Heating and Ventilation systems (HVAC)
• Better comfort for occupants

Research has shown that poor air tightness can be responsible for up to 40% of heat loss from buildings and also effect comfort levels for building occupants, hence the requirement for a test.

Organisations that provide commercial air pressure testing services should be registered as part of an approved testing scheme, such as the Air Tightness Testing & Measurement Association (ATTMA) or the Independent Air Tightness Testing Scheme (iATS).

EPS Group are members of the iATS Air Tightness Testing Scheme and are therefore able to guarantee that our Air Test Certificates will be accepted by all Building Control Bodies, no matter where you are based within the country.

Common Areas of Leakage identified during Commercial Air Pressure Tests 

The image shows a sample of the common air leakage areas within commercial buildings or non dwellings, however this is not exhaustive.

There are several key principles for constructing an airtight building:

• Identify the air barrier at an early stage of design
• Refer to airtightness in all contracts which may impact the air barrier
• Highlight the importance of the air tightness barrier to project teams
• Select Airtight components
• Check interfaces between components
• Ensure all site workers are aware of the importance of the air barrier
• Complete regular checks on the air barrier throughout construction
• Ensure that all works are complete prior to the final test

If you have any concerns prior to a commercial air pressure test, our technicians will be more than happy to discuss them.

We are also able to offer a mid-construction commercial air pressure testing service, which can eliminate problems at an early stage through the use of smoke tests or thermal imaging.

Commercial Air Test Diagnostics Service

EPS Group provide an air leakage diagnostic service, which can be particularly useful when used in conjunction with a commercial air pressure test.

Sometimes it can be difficult to locate areas of air infiltration within commercial buildings due to their size and complexity.

Thermal image cameras, smoke pens and smoke machines can be used alongside our air pressure testing equipment to quickly and efficiently identify areas of air leakage, and offer advice on cost effective solutions.

Smoke Pens – Used to identify all types of leakage.  Whilst a simple tool, they are still one of the most widely used and one of the most effective.

Thermal Imaging – Used to identify all types of leakage when environmental conditions are suitable. Proving there is an adequate temperature differential between the internal and external environment, thermal image cameras are an ideal way of both identifying and recording gaps in the air barrier.

Smoke Machines – Used to identify large or high level leakage.  Can be used under positive and negative building pressure and are particularly useful when trying to identify leakage at high levels or within areas that are difficult to access.

With EPS Group you can be confident in the advice that we provide.

EPS Group – The Full Package 

In addition to commercial air testing EPS Group can also provide SBEM Calculations and On Construction Energy Performance Certificates, meaning your part L compliance can all be dealt with under one roof.

Using EPS Group for all Part L services can be particularly helpful if you are having difficulty achieving the required air permeability result.  It may be that our SBEM Assessors can suggest a more cost effective alternative to undertaking further airtightness tests.

EPS Group are able to provide the following services: