exhaust ducting through new extension

[Steevo_Tabasco]

Hi,
Needing some advice - im planning a single storey extension to my home - and am doing the drawings myself, I live in a end terraced house my problem is the outside wall where my combi boiler exhausts is where i plan to have a new room ?? Can i simply use pipes/ducting to channel the exhaust gases either upwards through roof or along the the length of extension (7m) and vent ... the roof vent would be approximatly 750-1000mm below an upstairs window (both mine and neighbours)

Thanks
Steven

[Steve the gas]

No that run of flue is far too long, most flues will only cope upto 2.5 to 3m