Depends on how many grenades you have and how many rooms need clearing.
If I have to handle that little task in my own home, one of my first stops will be the photo darkroom where I keep the Sodium Thiosulphate and a few other chemicals, with which I'll fumigate the place before going room-to-room; I'm not in a hurry.
Those without photo supplies aroiund could make do nicely with a couple of gallons of ammonia, a six-gallon bucket and a couple more gallons of household chlorine bleach. A dozen or so housewives manage to accidentally kill themselves with that combination every year, no reason a couple of housebreakers or waiting burglers can't be added to those statistics.
-archy-/-
A couple of years ago, a man was doing some slight remodeling on our house. While talking with him he mentioned that his wife died from using ammonia and bleach as a cleaning agent.
Hey if a gobblin does wind up dying from such a chem mixture then the lawsuit against the homeowner will be even bigger than if it had merely been a justifiable shootiung. The tort lawyers will have a field day. Of course the homeowner might get lucky and they will go after the deep pockets of the bleach and amonia makers.
Stay well - Stay safe - Stay armed - Yorktown