97% Test results meeting or exceeding robustdetails® scheme standards of 2dB improvement over Building Regulations minimum standards.
2% Test results meeting or exceeding Building Regulation minimum standards, but failing to meet the robustdetails® scheme minimum standards. To date all amber grades have been caused by a failure to build in accordance with Robust Details specifications.
1% Test results failing to meet Building Regulation minimum requirements. In such cases Robust Details Limited is required to notify the housebuilder and Building Control Body. This may lead to pre-completion sound testing being requested on the site.