Technical Booklet G Resistance to the Passage of Sound·Page 21·1.19
Sub-grouping for material change of use
For material change of use, the same grouping principles apply as for new buildings, but differences in separating wall and floor constructions and flanking constructions are more likely, requiring more sub-groups and smaller group sizes. District councils should exercise judgement when setting up sub-groups.
The same principles as for new buildings apply, but in practice significant differences are more likely to occur between separating wall and/or separating floor constructions as well as the associated flanking construction(s) in a development. More sub-groups may therefore be required, and group sizes may be smaller. District councils should exercise judgement when setting up sub-groups.
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