Robust Details handbook

Robust Details (RDs) were developed as an alternative to pre-completion testing. A range of details have been developed which consistently satisfy (and exceed) the acoustic performance requirements specified in Approved Document E. The available RDs are published in a handbook by Robust Details Limited. A second edition of the Handbook is due for publication in January 2005.

To use a Part E Robust Detail in the construction process, builders must first obtain permission from Robust Details Limited and pay the requisite fee for each dwelling.  Provided that the robust details are built correctly, this will be accepted by all building control bodies in England and Wales as evidence that the homes are exempt from pre-completion testing. On completion of each separating floor and wall, the builder is required to complete a compliance certificate and pass it to their building control body. Without this certificate, the building control body will not approve the home.

The following is an extract from Approved Document E, Annex E (as amended in 2004) and should be borne in mind when considering the use of RDs.

It should be noted that the compliance of work with a robust detail, in circumstances where the correct procedures have been followed to attract exemption from PCT, is not a “deemed to satisfy” condition. The underlying requirement remains to achieve compliance with Part E1. The guidance in Approved Document E is that compliance will usually be established by the measured performance of the structure. Therefore it would be open to anyone, e.g. a homeowner, who considered that a party structure does not comply with Part E1, to seek to establish that by the carrying out of tests. It would not be a defence for the builder to show that he had correctly carried out a design detail approved by Robust Details Ltd, if the structure’s measured performance is shown not to meet the performance standards in Approved Document E.

However, all the RDs have undergone a thorough development and testing procedure. The performance of each RD is based on the mean result of 30 tests with no more than 8 of the tests being on the same site and involving at least two builders. The RDs have been shown to have acoustic performance considerably in excess of the minimum standards of the Building Regulations, in order to allow for variations in workmanship and quality. 

Procedures have been established to allow extension of the set of RDs as new details are proven. The requirements for achieving RD status are clearly quite onerous in a number of ways over-and-above the technical performance requirements.  The need to carry out a number of in-situ tests on a number of buildings (at the right time during construction) has had several consequences:

• The scope covered by the current RDs is quite limited
• There are various idiosyncrasies which reflect the scope of what was available for testing

RDs may only be used on new-build developments.