Anything 5KW or under won’t need an air vent unless you have a New build Property (built after 2008) or your property has been recently upgraded to a modern standard. If this is the case it must be a permanently open air vent within the room venting to the outside either straight through the wall of the room that the log burner is in, or one room away as long as there is air flow between the rooms.
Trickle vents on windows are fine as long as they can’t be shut.
The air vent aperture required increases in size depending on the KW, 550 square millimetres of vent hole per kW of the stove. When buying the air vent it should say the mm of air capacity, feel free to ask we can always work it out for you.
In older properties before 2008 then the rule is the same but you get the first 5kw free. In other words, a 5kw stove has no air vent requirements, whilst a 6kw will need 550 square millimetres of air permeability.
If you are worried about the draft of having an air vent but need a big kW stove then there is a way around it. You can sometimes come off the back of the stoves and go straight outside getting direct air with a non-combustible pipe.
Be sure to check that this is the case before buying your stove if this is what your planning on doing.
Unfortunately the majority of stoves don’t have this feature which is why a 5kw stove is often an atractive prospect, remember the bigger the stove the more wood you can burn and the more heat you will create, a small 5kw will not get as hot as a big 5kw stove, this is why some stoves have a nominal output as well as variable KW range.
Again its worth considering how warm the house is as well as how often you will be using the central heating.