It should not take a half an hour and leave me filthy, requiring a shower, to change the filters on two furnaces. Go figure, eh? At least I feel like I accomplished something. Long story short, the metal edges around the filter slot on the one for the apartment are pretty raggedy and would NOT let the old filter out. Of course that old filter was one of the ones w/ metal in them, so it was a real bitch to rip to shreds pulling out.