Business Focus: JosTec

TechRound recently caught up with Adam Joselyn of Hertfordshire based building acoustic testing company, JosTec. Adam is a director and co-founder of Jostec, which he started with his brother Robert, in 2011. Their expertise include air tightness testing, ventilation testing and commissioning and sound insulation testing. Over the last year JosTec have seen considerable expansion with increasing numbers of clients and developers utilising their services and reaping the significant benefits of an accredited and trusted, yet personable and friendly provider of this crucial and highly specialised service.

Their services span further afield than just Hertfordshire, with many clients being based in and around London. JosTec’s services ensure that buildings of all types are efficient in their performance and are fully fit for use and with the number of new builds in the UK rocketing, there has been an increased demand for many of JosTec’s services such as Sound Insulation Testing, Air Tightness Testing and SAP/ EPCs.

Hi Adam, so how did you get into air tightness and acoustic testing?

Rob had been working as an acoustic engineer for other companies for 6 years and had garnered all the knowledge he could, so was ready to go ahead and start up his own company. I had just finished a marketing degree and was still deciding what to do with it when Rob asked me if I wanted to join him in starting the company. I went on a course to become an air tightness tester, we started applying for our UKAS accreditation and JosTec was born.

What is air tightness testing and why is it so important?

Air tightness testing is the process of testing a house, flat or commercial unit for air leakage. The more air that leaks into or out of a dwelling, the more heating that is escaping. Thus the dwelling is less energy efficient, and heating bills are driven up. Air tightness testing was brought in to save energy as well as money for owners/tenants.

What is sound insulation testing and why is it so important?

A sound insulation test is a test to see how much airborne and impact sound is transferred between dwellings. The tests are carried out across party walls as well as floor/ceiling divides. They’re important because nobody wants to live in a house where they can hear every movement their neighbour makes. Poor sound insulation leads to a lower quality of life.

Sound testing measures both impact and airborne sound


When did you add ventilation testing & commissioning to your list of services?

We added ventilation testing to our repertoire about 3 years ago. The regulations for it came in in 2010, but amazingly we’re only now seeing building control officers asking to see the certificates. So in that respect, we got on board pretty early, and there won’t be too many companies who have been doing it longer than us.

Why is ventilation testing so important?

Dwellings with poor ventilation encounter problems with mould, damp and condensation. Many people don’t know this, but the trickle ventilators on the top of your windows are designed to stay open all the time. This is to ensure a constant stream of fresh air enters the building.

People often get sound testing and sound insulation mixed up, can you clear up the difference?

We offer a testing and consultation service, we don’t provide or install materials. The testing we do is to ensure that the sound insulation materials and system installed are up to scratch. If we were to supply or install materials, and then test it, that would be a conflict of interests. We are able to recommend trusted suppliers and installers if customers need us to though.

Who do you typically work with?

We work with anyone involved in creating dwellings. That could be architects, self builders, developers or construction companies.

How do I know if I need to arrange a consultation / testing?

If you’re building any new houses or flats, or converting a house/building into flats, you will need at least one of our services. If you’re unsure, it’s always best to check before you start your project.