We've just had a gas fire fitted in the living room and understand there is a requirement for a vent. it's a victorian house which is far from sealed and I intend to get a carbon monoxide alarm. We're most of the way through fitting a secondary wood floor and the plan was to put a vent into it to the underfloor cavity (we've recently made sure all the air bricks to the cavity are clear).
So two questions:
1) Given the general draughtiness of the house do we really need the air vent?2) if yes, how big. The figure of 100cm3 was mentioned but our local hardware stores don't carry stock and the minimum order requriements mean I'd look online. However the vents i've found (on andyplumb.co.uk) are measured, strangely, in inches. I'm presuming that 100cm3 does not equal a vent meauring 10cmx10cm but relates to the size of the holes.