"Griffo" wrote in message
oups.com...
I'm replacing a hearth and Building Regs Part J specify that the
constructional hearth has to have a depth of 500mm from the fireplace.
Unfortunately there is a wooden joist 460mm from the fireplace. If I
was to comply with the regs I would have to remove this part of the
joist. It all seems a bit much for 40mm. What are the consquences of
breaching the regs?

Depends on the inspector. Some will be a bit generous in how they hold the
measuring tape knowing what the problem is, others will just not approve it
and they don't really care what you have to do to fix it.

Is the project going to be inspected? If not, I'd just go ahead, but that
is me, I'm not condoning cheating. If it is going to be inspected, I'd
contact the local inspector, mention that you are fixing up an existing
hearth that was in before the regulations and ask how you can comply. It may
be as simple as putting a piece of sheet metal over the wood for added
protection. Or, since it is a repair, be allowed as is under the rules.