Technical Booklet B Materials and Workmanship·Page 7·24(2)
Urea formaldehyde foam cavity wall exceptions
In situ foamed urea formaldehyde may be used to fill cavities in cavity walls with brick or block inner leaves, provided it is suitable for the application and satisfactorily installed.
Insitu foamed Urea formaldehyde may be used for filling the cavity of a cavity wall having an inner leaf constructed of bricks or blocks, provided that it is—(a) suitable for such an application; and (b) satisfactorily installed.
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