Need Detailed rules on smoke growth from fire

[The_lone_gunman]

I am trying to make some very specific rules on smoke growth from fire inside a building. My players seem to think I am being a bit harsh, and I was wondering if anyone else has dealt with this issue. I would like to hear how you guys handle it, and will post my exact rules here when I get them done.

Thanks,

TLG

 

[jasper]

I assume you think about a true fire and not the standard smoking chimney.
How about a 5 foot by 5 foot by 1 ft high square per round. Starting at the ceiling and coming down each round.
obscurement 25 % if at 5 ft from floor
obscuremnt 50% at 3 ft
and 100 % at 1ft