Venting an Open Plan Living Space with two Gas Appliances Information, help and advice on many gas related subjects from gas fires to domestic appliances

[Pdooley1]

I have a large open plan kitchen living area in a sort of 'u' shape. Galley kitchen down one side, 3×5m extension on the back and the original living room on the return. I have a gas hob in the kitchen and a gas fire in the living room. Am I right in thinking there needs to be some sort of ventilation on an external wall. The hob is 5kw output and the fire is 3.7. Any advice appriciate