# residential footer



## TimNJ (Sep 7, 2005)

dutchlegacy said:


> Also, the print calls for the garage floor to be a minimum of 4" lower than the living quarters to avoid dangerous exhaust gases from creeping into the house.


 I never heard of that one. Is CO a heavy gas that settles low?

This is what I understand the reason for the step and the downslope to the garage door. If a car ever develops a gas tank leak or if somebody spills a gas can, or other flammable liquid for that matter, if there was no step in the floor level of the living space vs garage space the flammable liquid would run under your wall and into the living space. Second reason for anybody in snow country, when you pull into the garage and your car has a ton of snow packed on it and it melts, you don't want all that water running under your walls and doors into your living space either.


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