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Gas Membrane Verification

Coopers Engineering Consultants carry out independent inspection and verification of installed ground gas mitigation measures, inclusive of the sub-floor ventilation and ground gas membranes. Following the inspection of the ground gas membrane, verification reports are produced for issue to our clients and the warranty provider (NHBC, LABC, Premier) for the discharging of planning/land quality conditions.

Coopers’ ground gas design and verification works are carried out in accordance with BS 8485:2015+A1:2019 – Code of practice for the design of protective measures for methane and carbon dioxide ground gases for new buildings and the CIRIA 735 – Good practice on the testing and verification of protection systems for buildings against hazardous ground gases.

We carry out verification plans in accordance with CIRIA 735 to ensure that the ground gas mitigation measures installed are suitable for the regime (Characteristic Situation/NHBC classification) and that the membrane/ancillary products are selected and will survive the construction process. These are produced to ensure that the installation contractor is aware of their requirements and to satisfy the local authority/guarantor that sufficient verification will be undertaken and provided on behalf of the developer.

Our verification works are carried out predominantly on residential housing developments (Type A buildings) but can also inspect commercial and industrial units when requested (Type B-D).

Following the release of the BS 8485:2015+A1:2019 publication and dependant on the project specific criteria, independent inspection and verification is regularly a mandatory requirement to ensure minimal risk to life. We regularly inspect membrane systems designed to protect against the ingress of carbon dioxide, methane, VOC’s and radon. 

Coopers are one of the first 10 No. companies in the U.K. approved to be a member of the British Verification Council, an association of industry professionals/organisations looking to create a benchmark for high standards of gas membrane verification and to train junior engineers/installers and verifiers.

Coopers were involved in the production of the CIEH ‘Local Authority Guide to Ground Gas’. Coopers examples of verification reports are referenced and appended within the CIEH document and also within the information pack provided by Liverpool City Council’s guide to consultants.

Our validation reports include a description of the inspection regime, the specifics of the protection system, robust photographic records of the ground gas mitigation measures witnessed showing any defects/repairs, reference any integrity testing undertaken and a detailed inspection record sheet for each inspected plot to satisfy statutory bodies.

Coopers Engineer inspecting self-made tophat on Visqueen Ulimate HC Blok installationVisqueen gas barrier general membrane status with steel in place Visqueen Gas barrier installation at door threshold with steel reinforcement in placeVisqueen Detailing Strip self-made tophatVisqueen Detailing Strip self-made corner unitVisqueen Gas Barrier spanning external wall sectionsMembrane General Status for Visqueen Gas Barrier InstallationJointing Detail on Visqueen Gas Barrier MembraneDual pre-formed tophat on Visqueen low permeability gas membrane installationVisqueen Detailing Strip self-made corner unit

COOPERS is the trading name of Coopers (Chester) Limited.
Company registered in England & Wales. Company number 09730429.
Registered office Park House, Sandpiper Court, Chester, CH4 9QU

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