Possible Clues:

• It¿s on the house for heavy smoker in cold weather?
• Construction on a roof for getting rid of smoke
• Bum ciggy, ultimately nick matches for smoker?
• It's on the house for heavy smoker
• What may release smoke in YMCA's kitchen disastrously
• It's on the house for heavy smoker in cold weather
• My kitchen's hazy with a bit of cooking -- it needs this!
• Little bird sadly may nest inside here - and get burned?
• Roof flue structure