On Sat, 27 Jan 2018 09:51:06 -0800 (PST), George Miles
wrote:

But I've removed the loft above the bathroom: now the tank's at the top of a very tall room and over it is an OSB3 ceiling, 8 inches of kingspan , osb3 and an EDPM rubber roof.

Does the use of OSB3 in that arrangement comply with building regs particularly
with respect to spread of fire?
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