You could interpret this as “is the house being empty?”
The emptiness of the house here is a continuous state.
Why is the continuous state used for "empty"? What would be the meaning of "집은 비어요"?
Adding 있다 is much more specific for something that is currently happening at the moment of discussion. For this example it doesn't make tons of sense as the state of a house's emptiness is not very fluid. But it's the difference between "I eat meat" vs. "I am eating meat," "the house is empty" vs. "the house is empty [right now, ongoing]"
비다 is a verb, but its a passive verb. instead if the 고 있다 present progressive tense grammar active verbs get, passive verbs instead use
어/아 있다. the meaning of this grammar can be thought of as
"the completed and continued state of some action" as in the house became empty, and is continually empty; if that makes sense.
if you are wondering how to say "i empty something" 비우다 is the active verb equivalent.
나는 병을 비운다 i empty the bottle.