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Passive House is an approach to building design that sets the highest standards of energy efficiency in the world. Ensuring the building envelope is airtight plays a key role in this, requiring more air tightness tests to be carried out using a more rigorous methodology than for standard properties.
Our local passive house air testing engineers are always delighted to work on Passive House projects because the end product – a super energy-efficient, airtight building – has a higher energy performance than a typical property.
Also referred to as “Passivhaus”, or low energy air tightness testing, the main variations between a normal project and a Passive House one include the standards set (you need to achieve far lower air leakage scores), the process followed (the building must be pressurised, then depressurised), and the number of tests required (at least three tests must be carried out along the construction timeline).
Learn more about passivhaus air tightness testing and find answers to common questions in our FAQ section below.
Our expert sustainability surveyors are a team of experienced, friendly, and knowledgeable professionals well-versed in building testing. Get in touch today for a free consultation or competitive quote.
Why work with us?
Experience
Our testing engineers have over 25 years of combined experience, with thousands of tests under our belts.
There is not much we haven’t seen, meaning that we can provide on-site advice on every aspect of air tightness testing.
Quality
We consistently provide exceptional service to help clients pass their air test on the first visit, offering our knowledge to help them find leaks in their buildings and rectify any issues.
If your property is unlikely to pass, we will advise on how to fix this.
Speed
Our office-based staff work hard to book all appointments as quickly as the delivery schedule allows.
95% of all tests take place within two weeks of the initial booking, with the majority of certificates provided within 24 hours of the site visit.
Pricing
Our rate card prices for all services are reviewed regularly, so we’re confident that you won’t find a better service for a better price anywhere else.
If you think you’ve found one, we’ll either beat or match it.
Support
Navigating the complexity of energy efficiency, decarbonisation, and building regulation updates isn’t easy.
We’ve worked hard to explain a range of topics related to Passivhaus air testing in plain English to help non-experts get the information they need.
Get Your Passive House Air Tightness Testing Quote Today!
Looking for a fast and reliable passive house air tightness test in Bristol or nationwide?
Contact us today for a free quote and to discuss your specific project requirements. We offer competitive rates and prioritise fast turnaround times for all our clients.
Surveying an active shopping centre is logistically complex, but Building Energy Experts handled it with precision. Their report cut through the environmental variables to provide a clear distinction between maintenance quick-wins, like resealing doors, and the capital investment needed for insulation. It provided the exact technical evidence required to inform our roadmap to an EPC B rating and justify the retrofit budget.
Philip Emsley, UEC Energy – Thermographic Survey
In delivery of the Warm Homes: Local Grant programme in Shropshire, Building Energy Experts (BEE) have acted as invaluable partners to the Council. Their expertise in reviewing installer designs and liaising with our consortium of local installers has ensured the technical compliance and appropriateness of measures installed under the scheme.
Merrick Rose, Affordable Warmth & Energy Efficiency Support Officer, Shropshire Council – WH:LG Retrofit Coordination
The Council’s goal was to find a critical friend that ensures best practice and full PAS2035 compliance under schemes it delivers – BEE have brought this in spades, accompanied with a professionalism and pragmatism that has been indispensable in navigating the nuances and complexities of local authority led, domestic retrofit schemes. I would highly recommend engaging with BEE to any council or social housing provider considering an independent retrofit coordination model.
This entry provides clear evidence across multiple projects where Building Energy Experts has successfully forged strong partnerships, driving innovation and delivering outstanding outcomes.
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The organisation is more than a service provider; it is a trusted supply chain partner helping the built environment sector achieve real, measurable progress towards net zero by delivering tangible reductions in emissions, better energy performance and long-term cost savings. With a proven track record, cutting-edge technology and a sustainability-centred ethos, Building Energy Experts stands out as a transformative force in retrofit delivery.
I should like to say thank you so much to Rich and the team at Building Energy Experts for their efficiency and helpfulness in completing our commercial EPC survey in record time.
Margarita Hamilton, Walton Castle – Commercial EPC
Assessing a historic property like Walton Castle requires real expertise, and your team delivered exactly that. Not only did they complete this survey with a very quick turnaround but they went above and beyond by providing extra information and guidance which has been extremely helpful.
We are delighted with the final result and once again thank you from both myself and the team at Walton Castle.
What a great service you provided! As Self-Builders, with a great deal of red tape/bureaucracy to satisfy, you truly made this a real ‘value-add’ and reasonably priced exercise. We thought we were in reasonably good shape (having taken a lot of care and time on our build), but the checklist provided in advance of the test and the report post test, were really helpful in making improvements to the fabric of the building.
Tim Overton, Self-Builder – Air Tightness Test
Passivhaus Air Tightness Testing: Your Questions Answered
We’ve compiled answers to the most common questions about passivhaus air tightness tests to help you navigate this crucial tool for energy efficiency.
What is a Passivhaus (or Passive House)?
Passivhaus is a world-leading standard for building energy-efficient homes. It’s a design and construction methodology that creates ultra-low-energy buildings that require very little energy for heating or cooling. A certified Passivhaus is built with meticulous attention to detail and features super insulation, minimal thermal bridging, and exceptional airtightness to provide maximum comfort with a minimal environmental footprint.
What is the airtightness requirement for a Passivhaus?
The airtightness standard for a Passivhaus is extremely strict. A building must not have more than 0.6 air changes per hour (ACH) when pressurised to 50 Pascals (n50≤0.6 h−1). This is significantly more stringent than the requirements for a standard new build in the UK.
How is a Passivhaus air test different from a standard air test?
While both tests use a blower door fan to measure air leakage, the Passivhaus test is much more rigorous. The key differences are:
– The Target: The airtightness target of 0.6 ACH is far lower and harder to achieve than for a standard build.
– The Method: Passivhaus testing uses ‘Method A’, which measures air changes per hour based on the building’s volume (m3/h.m3 @ 50Pa). Standard UK tests typically use ‘Method B’, which measures air permeability based on the building’s envelope area (m3/h.m2 @ 50 Pa).
– The Procedure: A Passivhaus test requires both a pressurisation test and a depressurisation test to be carried out. The final result is the average of these two figures. The data logging and environmental readings are also more extensive.
How many air tests are needed during a Passivhaus build?
Unlike a standard build which may only have one final test, a Passivhaus project typically requires multiple tests throughout the construction process to ensure it stays on track. It is common to test at least three times:
1. Stage 1: After the initial air barrier is complete.
2. Stage 2: After second-fix works are complete.
3. Stage 3: At completion for final certification.
Testing at these key stages helps to identify and fix leaks early, which is critical for meeting the final target.
What are the different Passivhaus certification levels?
There are three main certification levels, each with increasing requirements for energy efficiency and on-site renewable energy generation:
1. Passivhaus Classic: The foundational level, focused on achieving exceptional airtightness and insulation to minimise energy use.
2. Passivhaus Plus: Builds on the Classic standard by requiring the home to produce as much energy as it consumes through renewable sources.
3. Passivhaus Premium: The highest and most demanding level. The home must generate significantly more energy than it uses, with the potential to be a net contributor to the power grid.
Can existing buildings be retrofitted to a Passivhaus standard?
Yes. For retrofit projects where the original architecture makes meeting the full Passivhaus standard unfeasible, the EnerPHit standard can be used. This is a slightly relaxed but still very challenging standard for achieving exceptional energy efficiency in existing buildings.
