The refashioned the roof vents out of old iron floor grates from a remodel in NE portland a few years ago. (treehugger.com)
Once the troops figure out that you're popping out of floor grates to incapacitate them, they'll toss an incendiary grenade down there to flush you out and destroy a few grates. (tomsguide.com)
Ohhhhh, I LOVE those wooden floor grates, so nice! (meeganmakes.com)