Air Tightness Testing and
Pressure Testing Services

Air Tightness Testing and Pressure Testing Services

Understanding air tightness and why it matters

Air tightness testing, sometimes called air permeability, or air pressure testing, is required for many new buildings under Part L of the Building Regulations in England. Whether testing is required depends on the type of building, the work being carried out and the applicable regulatory standards.

This test measures the air permeability of the completed building envelope by measuring uncontrolled air leakage through unintended gaps and openings. The result forms part of the evidence used to demonstrate compliance where testing is required.

Why is this so important?

Excessive air leakage can increase heat loss, affect energy performance and, where air tightness testing is required, may prevent the building from achieving the required compliance result. Every developer, contractor, or building owner wants to avoid delays and extra costs at sign-off, but more importantly, improved air tightness delivers real operational benefits. It helps meet sustainability targets while creating more comfortable, energy-efficient spaces for the people who live or work there.

Where pressure testing is required, the measured air permeability result is used within the SAP calculation for dwellings and contributes to the evidence supporting Building Regulations compliance and EPC production. Engaging early with a qualified provider helps reduce the risk of last-minute issues and can identify opportunities to improve performance before construction is finished.

Send us your project details and we’ll send a quote

Our air tightness and pressure testing services

We support projects of every scale, from single homes to large commercial developments. Our comprehensive service covers:

Early-stage design advice

Reviewing your plans, we highlight potential air leakage paths and suggest practical steps to avoid costly issues at test stage.

Flexible booking and rapid response

With a UK-wide network of trained assessors, we can usually schedule your test within five days, or faster if you need a 24-hour turnaround.

Accurate on-site testing

Using calibrated blower door equipment, we perform air pressure tests in line with ATTMA or IATS standards.

Registered certification

After the test, we provide a fully compliant certificate of air permeability, suitable for Building Control evidence, SAP calculations and EPC production where applicable.

Clear feedback and retesting support

If the initial test does not achieve the required air permeability target, we offer practical guidance to help you pass on retest.

Early-stage design advice

Reviewing your plans, we highlight potential air leakage paths and suggest practical steps to avoid costly issues at test stage.

Flexible booking and rapid response

With a UK-wide network of trained assessors, we can usually schedule your test within five days, or faster if you need a 24-hour turnaround.

Accurate on-site testing

Using calibrated blower door equipment, we perform air pressure tests in line with ATTMA or IATS standards.

Registered certification

After the test, we provide a fully compliant certificate of air permeability, suitable for Building Control evidence, SAP calculations and EPC production where applicable.

Clear feedback and retesting support

If the initial test does not achieve the required air permeability target, we offer practical guidance to help you pass on retest.

How our process works

Our approach is designed to make air tightness and pressure testing straightforward and hassle-free, with clear guidance at every step. From initial enquiry to final certification, we keep the process transparent so you know exactly what to expect.

01

Send us your plans or drawings for review

We check your documentation and highlight any likely air leakage paths, offering practical recommendations where needed.

02

Book a test date to suit your schedule

Choose a convenient time. We offer rapid appointments UK-wide, often within five days or less.

03

On-site testing by a qualified assessor

Our engineer arrives with specialist blower door equipment, conducts the test, and provides instant feedback.

04

Receive your official certificate and advice

We issue a registered certificate of air permeability. If there are issues, you’ll get clear advice on next steps to achieve the required air permeability result.

Why enevo for air tightness and pressure testing?

Over 15 years' experience delivering air tightness testing across residential, commercial and mixed-use developments throughout the UK.
All assessments carried out by engineers registered with ATTMA or IATS, ensuring full compliance and professionalism
National coverage, with local assessors for quick, cost-effective service wherever your project is based
Practical, straight-talking advice from specialists who are focused on helping you achieve compliance efficiently and affordably
Trusted by developers, architects, and contractors nationwide for fast response times and dependable results

How can we help you
with your project?

Trusted, Time And Time Again

Harry gave me excellent advice and clear understanding on what BREEAM means as well about the specific accredited assessing required by professionals like Harry.

Angela Singh

Very efficient and professional service. Cant recommend enevo enough, glad I chose them for my project.

William Brannon

Very impressive on all aspects of energy calcs. Responsive and cost competitive. Highly recommended

Nick Spencer

enevo are always helpful, friendly and efficient in carrying out SAP calculations for our clients.

Lizzie Hicks

enevo were fantastic from start to finish and helped make each step of the project run smoothly. I would highly recommend and we will definitely be using again, if needed in the future.

Rees Doyle

We have always found enevo to provide an excellent service in the preparation of SAP Calculations and Assessments as well as EPC Certificates for projects that they have worked on for us. They are also reasonably priced so we would certainly recommend them to anyone looking for this type of service.

Martin Booker

Used enevo from start to completion of our recent project of 2No. new builds. Services included SAP/EPC and property air testing. Great service, understanding of requirements and cost. Person friendly company and good with communication.

Mark Radcliffe

Very efficient, personal, professional service, with a quick report turnaround. Highly recommended if you're a self-builder trying to navigate the complexities of the latest regulations.

Edward Broadhead

Always efficient and prompt service, enevo are an asset to my company, having used their services on multiple developments I wouldn't hesitate to recommend them.

Mac Chappell

Great service with a fast turnaround. Communication was excellent throughout. Richard the engineer was polite and professional. Will certainly be using enevo again.

ECO PROPERTY DEVELOPMENTS LTD

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We’re Ready To Help

Air Tightness Testing

We’re Ready To Help

Air Tightness Testing

03301 901 200

info@enevo.co.uk

Air Tightness Testing and
Pressure Testing Services