Lobster wrote:

Could it be drains-related at all?

I ask because we had occasion to summon Transco over a smell of gas
outside the house - on our brand-new drive as it happens! We suspected
the contractors might have stuffed our gas pipe in fact; but after
spending the best part of a day poking around in the ground with
sensors, it turned out that the problem was somewhere under the road, 30
yards away, and gas was somehow leaking from the supply pipe and getting
into the sewage system, from where it was wafting up the pipes and out
of a surface drain on the drive!

Now, that is interesting because there is an occasional whiff of gas
outside near the drain covers. But I've always put that down to one or
other of the nearby boilers purging.
Something to think about though.

Lee
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