{"id":943,"date":"2022-01-25T12:19:21","date_gmt":"2022-01-25T12:19:21","guid":{"rendered":"https:\/\/thermal-economics.co.uk\/acoustic\/?post_type=news-post&p=943"},"modified":"2024-03-27T13:49:26","modified_gmt":"2024-03-27T13:49:26","slug":"robust-details-is-only-as-effective-if-the-contractor-is-aware-of-the-robust-details-requirements","status":"publish","type":"news-post","link":"https:\/\/thermal-economics.co.uk\/acoustic\/news-post\/robust-details-is-only-as-effective-if-the-contractor-is-aware-of-the-robust-details-requirements\/","title":{"rendered":"Robust Details is only as effective if the contractor is aware of the Robust Details requirements"},"content":{"rendered":"
[vc_row][vc_column][vc_column_text]Reducing sound transmission is often thought to be a \u2018dark art\u2019 because the performance of sound insulation cannot be calculated in a similar way to thermal insulation, and the commonly held rules of thumb that are logical for heat transmission, do not hold true for sound.\u00a0 This creates a risk in design, because the performance criteria for Part E in the Building\u00a0Regulations depends on results obtained from pre-completion testing.\u00a0 That is to say, you won\u2019t know if the Building Regulations have been met until the work is already done.<\/p>\n

Some examples of separating wall and floor constructions are given in Approved Document E.\u00a0 However, these examples are not guaranteed; and although the risk of failing is less, a poor sound test result could have costly consequences as remedial work will have to be carried out.<\/p>\n

Robust Details offer a more pragmatic approach: prescriptive wall and floor constructions that satisfy Part\u00a0E requirements without pre-completion testing.\u00a0 No pre-completion testing, no depending on test results, no risk.\u00a0 However, any deviation from the Robust Detail will mean that Regulation 41 no longer applies; so how \u2018robust\u2019 are Robust Details?<\/p>\n

How does Robust Details work?<\/h2>\n

Robust Details are a private limited company who oversee the approved \u2018Robust Details\u2019 referenced in Regulation 41 of the Building Regulations (SI 2010 \/ 2214<\/a>).\u00a0 These details are listed in the Robust Detail Handbook, freely available for download from\u00a0www.robustdetails.com<\/a>.<\/p>\n

The construction details are examples of floor and wall constructions using specific proprietary products that have already undergone on-site testing and continue to satisfy Robust\u00a0Details\u2019 quality assurance requirements.\u00a0 Therefore, building to a registered Robust Detail means that pre-completion testing does not need to be carried out, saving time and money during construction.<\/p>\n

Although a site doesn\u2019t have to be registered with Robust Details to use Thermal Economics\u2019 IsoRubber sound insulation products, many are; and Robust Detail E-FC-4 remains the most often used detail, featuring IsoRubber Base underneath a screed on precast concrete planks.\u00a0 As IsoRubber Base is a specified proprietary component listed as the resilient layer in E\u2011FC\u20114, any substitution for another product would invalidate the registration and require pre-completion testing.<\/p>\n

Using the right products to meet the requirements of Robust Details<\/h2>\n

Unfortunately, Thermal Economics has become aware that in some isolated cases, IsoRubber\u00a0Base is not being installed on sites registered as Robust\u00a0Detail E\u2011FC\u20114, and cheaper products have been installed instead.\u00a0 This means that the requirements of the Robust Detail haven\u2019t been met, and therefore the floor construction no longer satisfies the Building Regulations without pre-completion testing.<\/p>\n

However, this also raises an interesting question of liability.\u00a0 Who should pay for the pre-completion testing, and who will pay for any remedial work to be carried out?<\/p>\n

Is there vicarious liability?<\/h2>\n

One could argue that the site manager has vicarious liability because the error occurred in the course of employment.\u00a0 Vicarious liability means that a person is also liable for damage caused by the negligence of those in that person\u2019s service, as long as the negligent act was carried out whilst in the person\u2019s commission.<\/p>\n

However, when the contractor knows that the plot is registered as a Robust Detail and has been informed of the requirements of the Robust Details scheme, then the resilient layer is a proprietary product. The contractor making any amendments to the design or specification of the building element (such as product substitution) would be doing so on a\u00a0frolic of his own<\/a>, and\u00a0the contractor would be wholly liable for any and all costs incurred<\/strong>.<\/p>\n

Make sure Robust Details are achieved<\/h2>\n

The most important action for the site manager is to ensure that the contractor is fully aware that a Robust Detail has been specified, and what the requirements of that Robust Detail are.\u00a0 Thermal Economics products are specified in six proprietary Robust Details, and one semi-proprietary Robust Detail for separating floors; and provide free on-site training to site managers and contractors apropos correct installation and the requirements of the Robust\u00a0Detail for Regulation 41 to apply.<\/p>\n