Alternate Vent Hole
All these days, we had been using cement based cylindrical shells for constructing exhaust (fan) vents. But here is an example of how one can become much more conservative. These photos were taken at Taylor's Road, Chennai, where Pizza Hut is building their new outlet. The construction engineer should have thought of reusing a plastic bucket at his house. It could also be the case of using the bucket as a die for the vent hole. I personally liked this idea of using a plastic bucket for a vent hole.