Part J: help interpreting combustible materials regs

23 Sep 2012
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United Kingdom
Hi all,

Having a challenge interpreting Part J of building regs, specifically distance from log burner to combustible materials; in this case an oak mantel we are about to install. Our Stovax Stockton 5 stove just lists ‘N/A’ as distance required above the stove. My (perhaps incorrect) understanding is that many stove manufacturers don’t list a distance for above stoves as the regs are so difficult to interpret!

The stove is set back in a masonry fireplace and all installed by Hetas registered company etc. We weren’t ready to install a mantel at that time so now doing it ourselves.

I think the regs might suggest 200mm to any combustible material but cannot work out if that’s from top of stove or from flue liner; a linear distance (e.g. from edge of flue to front face of fireplace aperture then balance of 200mm upwards to bottom of mantel), or line of sight etc.

Can anyone please shed some light?

Thanks in advance
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Normally 300mm to combustable from top of stove.
Originally we had oak beams to go around the fireplace opening, however couldn't get it to work as we had a logstore ivar 5 and I wanted the hetas guy to sign it off.
He fitted the liner and the actual fire, I did the opening up and Cladding of the fireplace.

In theory you can have the oak beam with a heat guard (hardibacker) and 25mm airgap and reduce the distance.

In the end I got an old piece (125 years) of bevelled chunky slate and some nice cast in style ornate brackets.
The temperature gets up to 50c easy on top of slate. But temperature would have to 232c to autoignite paper.


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