Technical Booklet B Materials and Workmanship·Page 17·3.3
Conditions for insulating suitable cavity walls with urea formaldehyde foam
Urea formaldehyde foam may be used in suitable cavity walls only when the inner leaf is masonry, the installer is certified, the foam meets BS 5617, and installation follows BS 5618.
A cavity wall which has been determined to be suitable for foam filling may be insulated with urea formaldehyde foam where – (a) the inner leaf of the wall is built of masonry (bricks or blocks); (b) the person carrying out the work holds (or operates under) a current Certificate of Registration of Assessed Capability for the work to be undertaken; (c) the insitu foamed urea formaldehyde is manufactured in accordance with the relevant recommendations of BS 5617; and (d) the installation is in accordance with BS 5618.
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