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Rated 5 out of 5 stars

I had Adam carry out test on my property 2 times. Both times I have had him he's been excellent. He is very knowledgeable and tells you exactly what he's doing and how it works. He offers recommendati... See more

Rated 5 out of 5 stars

I would highly recommend JosTec. Always professional, they showed flexibility to arrange the appointment at the time it suited me. They were super efficient and friendly.

Rated 5 out of 5 stars

Very smooth, clear and reactive. We used JosTec from recommendation and the quote was very fast & thorough (it included items we didn't end up needing so there were no hidden costs: just pleasant surp... See more

Rated 5 out of 5 stars

We needed a single company who could do all the Acoustic tests and Water calculations reports etc. required for Building Regulations and are very pleased to use RJ Acoustics as our single partner to... See more

Company details

  1. Building Consultant

Written by the company

JosTec (formerly RJ Acoustics) are experts in numerous Building Regulations Compliance Services. We offer sound insulation testing for Building Regulations Part E, air tightness tests, SAP calculations, SBEM calculations and EPCs for Building Regulations Part L1, ventilation testing and commissioning for Building Regulations Part F, water efficiency calculations for Building Regulations Part G, and all types of noise assessments and surveys. We also offer consultation services, giving you the best chance of passing your testing first time.


Contact info

4.9

Excellent

TrustScore 5 out of 5

95 reviews

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Rated 5 out of 5 stars

I would highly recommend JosTec

I would highly recommend JosTec. Always professional, they showed flexibility to arrange the appointment at the time it suited me. They were super efficient and friendly.

May 1, 2026
Unprompted review
Rated 5 out of 5 stars

I had Adam carry out test on my…

I had Adam carry out test on my property 2 times. Both times I have had him he's been excellent. He is very knowledgeable and tells you exactly what he's doing and how it works. He offers recommendations and very he is very professional and I would highly recommend JosTec and Adam in particular, he is a real asset to the business.

April 27, 2026
Unprompted review
Rated 5 out of 5 stars

Kai was as always so helpful and…

Kai was as always so helpful and accommodating making sure we got our tests carried out quickly and efficiently without any disturbance to site.
Highly recommend using Jostec!!

March 16, 2026
Unprompted review
Rated 5 out of 5 stars

Professional service

Good service, arrived on time, very professional and Kai was very helpful in explaining the process and helping with our queries.

March 3, 2026
Unprompted review
Rated 5 out of 5 stars

Excellent service from a friendly firm

Very helpful firm. Mostly, they worked with my architects, but I had several discussions with them, specifically about SAP calculations, which were very helpful.

Getting building regs. sign-off now is a huge struggle, especially for conversions, but Jostec have been very helpful to me in this regard.

December 3, 2025
Unprompted review
Rated 5 out of 5 stars

Jon Stone @ Jostec

We’ve worked with Jon for several years as our technical assessor through Jostec, and his professionalism and expertise have always stood out. Jon has a deep understanding of energy related systems and consistently provides clear, practical advice that helps us make informed decisions.

He takes the time to understand our business needs, ensures every recommendation is tailored to our situation, and is always approachable and responsive whenever questions arise. His proactive approach has saved us both time and costs over the years.

It’s rare to find someone so knowledgeable who also communicates so clearly and genuinely cares about client success. We can’t recommend Jon highly enough for anyone looking for dependable, expert energy support.

November 5, 2025
Unprompted review
Rated 5 out of 5 stars

highly recommended

Kai was absolutely amazing. He was incredibly kind and helpful and did an extraordinary job carrying out the sound test. He maintained a very calm and professional demeanor throughout the entire process. Highly recommended!

October 30, 2025
Unprompted review
Rated 5 out of 5 stars

Our engineer, Haresh

Our engineer, Haresh was professional and arrived promptly. He was very polite and helpful. The entire process was very smooth from receiving the quote, arranging the survey date and the certificate was issued onsite. Very efficient - highly recommend.

September 19, 2025
Unprompted review
Rated 5 out of 5 stars

fantastic service from JosTec

fantastic service from JosTec

Our engineer Kai, arrived bang on arranged time, and was extremely helpful explaining all the tests and processes.

This is second time we have used this company and would highly recommend.

Vic

August 29, 2025
Unprompted review
Rated 5 out of 5 stars

Amazing support and guidance

We have had a long and tricky road to completing soundproof tests on our property and this was all made so much easier with the help of the team at JosTec. Their patience and guidance made the whole experience a lot easier to deal with. Sol was calm and knowledgeable on completing our tests with such ease after great advice from our initial visit. Thank you.

May 14, 2025
Unprompted review
Rated 5 out of 5 stars

Absolutely amazing service…

Absolutely amazing service from Rob, Adam and especially John Stone at JosTec.

The whole team at is amazing company has gone over and above to assist us in all of our requirements to do with energy and assessments and never let us down. Thank you very much for the great service.

May 8, 2025
Unprompted review
Rated 5 out of 5 stars

Very smooth and pleasant experienc

Very smooth, clear and reactive. We used JosTec from recommendation and the quote was very fast & thorough (it included items we didn't end up needing so there were no hidden costs: just pleasant surprises). The survey happened smoothly, and it took about 10 days after paying the invoice to get the report back, which included everything and was promptly accepted by building control.

May 1, 2025
Unprompted review

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