Technical Booklet G Resistance to the Passage of Sound·Page 80·3.72
Floor 2.2B joint positioning
When floor type 2.2B is used with planks parallel to the external wall, the first joint must be at least 300 mm from the cavity face of the inner leaf.
Where floor 2.2B is used and the planks are parallel to the external wall the first joint should be a minimum of 300 mm from the cavity face of the inner leaf (see Diagram 3.16).
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