Most insurance documents have a specific clause forbidding the transport of any highly flammable substance. This could be petrol, diesel or gas (amongst other things).
The quantity is irrelevant,.. even a gallon of petrol for your lawnmower voids your cover in most cases.
This affects DIY gas systems, as well as any diesel system with a separate fuel tank.
My insurer wasn't bothered in the slightest about a 650 litre tank or the gas heater system,.. they were simply caught up on the gas bottle.
I have researched it, and in Ireland it is completely legal to carry a huge amount of gas without any special license etc,.. once its secured in an upright position,.. so its not a law that is the issue, simply the insurers assessment of risks.
I have cover now with Quinn insurance, who were more expensive than many of the quotes I got, but are happy to give me cover for the gas bottle.
