Retrofitting hazardous ground gas protection measures

Join us for this pre-recorded webinar for an introduction to CIRIA's guidance Retrofitting hazardous ground gas protection measures in existing or refurbished buildings (C795), and to learn how to manage ground gas problems.

This webinar was first broadcast in January 2021.

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Hazardous ground gases are a problem in the UK, where residential buildings have an average lifespan of more than 100 years. Some buildings may not have adequate gas protection measures in place, while those that do can find that the effectiveness of their gas mitigation measures has been diminished by increasing rainfall and severe weather events.

This pre-recorded webinar provides an overview of CIRIA’s guidance Retrofitting hazardous ground gas protection measures in existing or refurbished buildings (C795). Expert speakers discuss how the risk assessment process should be carried out to determine the scope of the process, as well as the main principles, pros and cons of various gas protection measures for ground works and basements.

Why attend
Learn how risk should be assessed for different types buildings including
Understand the pros and cons of ventilation, sealing of preferential migration
pathways, membranes and sub-slab works in ground works
Hear how other building performance requirements, such as water and damp
penetration, condensation, fire resistance, structural performance, and disabled
access, should be considered as part of the retrofit design
Discover how verification should be carried out
Master how to select the appropriate gas protection measures for your building

Who should attend
Ground gas specialists
Local authorities

Wednesday 25 August 2021
14:30 - 15:30

14:00 Welcome and introduction
Joanne Kwan, Project Manager, CIRIA
14:15 Retrofitting ground gas protection measures – how can CIRIA’s new guidance
(C795) help?
Hugh Mallett, Technical Director, Buro Happold and
Steve Wilson, Technical Director, Environmental Protection Group
14:35 Interactive discussion and Q&A
14:55 Closing remarks

CIRIA members Free
Non-members £35 + VAT

Please sign in or create an account to register online for this event.
If you are experiencing issues registering online, please complete and return the booking form to Sarah Macpherson.
Alternatively please contact us on 020 7549 3300 or email

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25/08/2021 - 25/08/2021

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