Clear cat urine smell from house

[Brendan L.]

Buying a duplex and the previous tenants on one side let their cats destroy the place. Very strong smell of cat urine. Place is covered in carpet. I'm expecting the replace everything including subfloor in 1000 sq feet. I have a feeling this won't be enough to wipe the smell away permanently. What do you suggest?

[Julie Thevenow]

pull the carpet and paint with oil base Kilz. I've done several this way and the odor is gone.