Air Tightness Testing

Air leakage occurs through openings in the building envelope, this air leakage affects the building’s energy performance, The need to reduce CO2 emissions has led to changes in building regulations, therefore buildings now need to meet a level of air tightness. The air-tightness of a building is the air permeability or leakage rate through a structure. Air leakage is the uncontrolled flow of air through the building envelope; this does not include the structure ventilation system.

To determine if building regulations for air tightness are met, a test is carried out, which usually involves placing a blower-fan in the doorway of the structure and pressurising the building envelope. These measurements are used to calculate the air tightness of the structure. A certificate is produced which will be passed on to the SAP assessor who is responsible for assigning a buildings energy rating. In the case of buildings that have an existing energy rating, this process can be used to easily improve it’s grading. This test must be carried out after all building works are complete.

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Why Do I Need Air Tightness Testing

Building Regulations states that dwellings are tested before completion, to demonstrate suitable air tightness, in compliance with the Building Regulations for England and Wales.

Our accredited engineers test to the current standard and we only use UKAS calibrated equipment, as stated in the building regulations

Our team are here to give advice, to help you achieve the required results.

Air Tightness Testing & Compliance

Compliance with building regulations Part L is mandatory with new builds, the aim is to reduce CO2 emissions by improving energy performance. Demonstrating compliance with Part L is relatively easy to achieve, removing uncontrolled air flow or air leakage creates a more cost-effective building in terms of operational costs but also a more comfortable environment. A sustainable building will be an airtight building but controlled ventilation is also required, to remove pollutant laden air and replace it with fresh air through controlled ventilation, this will also remove excess moisture which can have a negative effect on the occupant’s health and the structure of the building.

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Why You Should Choose AF Acoustics For Your Air Tightness Test

Our team of air tightness test engineers test new builds and conversions. We work with everybody, from first time developers, to large construction firms. Our services help them comply with building regulations.

We can provide next-day certificates when needed. Generally, our clients find the biggest cost benefit when they involve us early in a project as our expert advice helps clients avoid costly remedial work therefore ensuring all their tests pass first time.

We pride ourselves on delivering an honest and friendly service, which we fell helps our clients to get their projects compliant and signed off by an approved building control body.

When Do I Need an Air Tightness Test?

Testing is normally performed post second fix. All major penetration to walls and floors must have already been made. Additionally, you will need:

  • All service penetrations sealed
  • Trickle vents installed
  • Loft access hatch in place
  • Plumbing complete with water in the traps
  • Seals fitted on external doors
  • Electrical outlets fitted

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