About Us

Our Story

We help build your visions

Aldas are the most experienced airtightness testers and consultants in the UK, Paul with nearly 40 years of experience alone.

Aldas are experienced trainers and originated the “Airtightness Champion” concept, as well delivering numerous on-site trainings and many CPD seminars to architects and builders. Aldas developed the 12 Steps to Airtightness approach to enable UK contractors to reliably deliver airtightness in Passivhaus and other low-energy projects.

Airtightness Consultancy
Design advice & Planning

Airtightness Testing
Training courses & CPD

What We Offer

Aldas offer a range of services to help you achieve the best Airtightness for your project.

Design Planning & Consultancy

The key to achieving good airtightness is in the planning and design phase

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Airtightness Testing

Aldas are the most experienced Airtightness testers and consultants in the UK

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Airtightness Training

Aldas are able to offer both on and off-site training in airtightness to help you achieve minimal air leaks

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Our Team

Aldas is a collective of different people coming together to reliably deliver airtight buildings

Paul Jennings

Airtightness consultant. FOUNDER

Paul Jennings of Aldas is the most experienced airtightness tester and consultant in the UK, with nearly 40 years of experience.

Paul is an experienced trainer and originated the “Airtightness Champion” concept, as well as delivering numerous on-site trainings and many CPD seminars to architects and builders. He developed the 12 Steps to Airtightness approach to enable UK contractors to reliably deliver airtightness in Passivhaus and other low-energy projects.

He has presented at many conferences and demonstrated test equipment at others. He has also given talks at Passivhaus conferences in Vancouver and Germany, as well as in the UK. Paul has been involved in most UK Passivhaus projects in one or more capacities. He is also a Director of the UK Cohousing Network.

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Mischa Hewitt

Airtightness consultant

As well as working with Aldas, Mischa is an energy consultant with Earthwise with a particular interest in affordable low energy buildings made from natural materials. He has been working on domestic and commercial environmental buildings since 2003 and holds an MSc in Sustainable Architecture with Distinction from the Centre of Alternative Technology.

Mischa is a Certified Passivhaus Designer and Air Pressure Tester. He is the co-author of the book Earthships in Europe and has written numerous articles on sustainable construction. Mischa is also a Trustee of the AECB – the Sustainable Building Association.

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Projects

Some of the major projects Aldas have been involved in as airtightness testers, trainers and quality control consultants

Airtightness-Testing-of-the-St-Sidwells-Point-Leisure-Centre

St Sidwells Leisure Centre, Passivhaus, Exeter

Aldas provided airtightness design guidance and extensive preliminary air leakage investigations. Testing of mock-up assemblies and partial sections, followed by preliminary and acceptance air tightness testing were undertaken by Aldas. The newbuild Passivhaus leisure centre, at St Sidwell’s Point in Exeter, passed its final test just before Christmas 2021

Agar Grove,
Passivhaus Newbuild, London

The Agar Grove estate in Camden, North London, is being re-developed in stages to provide new build Passivhaus accommodation, ultimately delivering over 500 units. Aldas carried out preliminary and acceptance testing of Phase 1A and extensive preliminary and investigative testing of the four blocks in Phase 1B, including managing remedial sealing works in three problematic stairwells

Erneley Close,
EnerPHit Refurb, Manchester

The first major EnerPHit project in the UK, the two run-down Erneley close social housing blocks were transformed with full enveloping, airtightness and MVHR systems. Aldas provided initial training for the site airtightness champions team and extensive preliminary and acceptance airtightness testing. Since completion, residents report affordable comfort and great satisfaction

Larch House,
Newbuild Passivhaus, Warwickshire

Larch house is the most airtight dwelling in the UK to date, achieving a zero Passivhaus airtightness (0.048 AC/hr @ 50 Pa) in Spring 2019. Self-built by a dedicated engineer, ably assisted by a German trained master carpenter, this cross-laminated timber (CLT) set a new standard for airtightness in the UK. Aldas’s testing required re-calibration of our fan for very low airflows!

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