Sacred Scripture tells us that just as individuals can become spiritually defiled, homes and property can also be defiled:
"Do not defile yourselves in any of these things: for in all these the nations are defiled which I cast out before you: And the land is defiled: therefore I do visit the iniquity thereof upon it, and the land itself vomits out her inhabitants."-Leviticus 18:24,25
There are some nations that are more heavily under demonic influence than others. In the book of Revelations, the Bible speaks of how a country or land can become inhabited with unclean spirits:
"And he cried mightily with a strong voice, saying, Babylon the great is fallen, is fallen, and is become the habitation of devils, and the hold of every foul spirit, and a cage of every unclean and hateful bird."-Revelations 18:2
Land, homes and even buildings can become habitations of demonic entities. Such situations are not called possession, since this pertains to humans proper, but as infestation. Think of it the same way you would if your garage were infested with mice.
There are many signs we can look for in an infested home or building. Some of the things a person can look for are doors slamming when nobody is there, strange noises, reputation for calamities (people being pushed down stairs, scratches, bites, etc.), the air seems heavy (making it harder to breathe), animals acting fearful (dogs barking in excessive anger for no reason), and so forth. While these potential signs are not definitive, they are some warning signs of potential demonic infestation.
How do homes and land become infested?
Sins of the inhabitants: One of the ways in which a place can become defiled is through the deeds of its inhabitants. If things such as seances, voodoo, adultery, or incest have been practiced in a home, then demonic entities may inhabit there. The Word of God tells us that the deeds of its inhabitants can defile even the land on which it is practiced:
"Defile not ye yourselves in any of these things: for in all these the nations are defiled which I cast out before you: And the land is defiled: therefore I do visit the iniquity thereof upon it, and the land itself vomiteth out her inhabitants... (For all these abominations have the men of the land done, which [were] before you, and the land is defiled;)"-Leviticus 18:24-25,27
"And it came to pass through the lightness of her whoredom, that she defiled the land, and committed adultery with stones and with stocks."-Jeremiah 3:9
"Son of man, when the house of Israel dwelt in their own land, they defiled it by their own way and by their doings: their way was before me as the uncleanness of a removed woman."-Ezekiel 36:17
"And I brought you into a plentiful country, to eat the fruit thereof and the goodness thereof; but when ye entered, ye defiled my land, and made mine heritage an abomination."-Jeremiah 2:7
Possession of Cursed Things: Another means by which a home can be defiled is through the possession of cursed items, such as idols, occult books, rings, satanic symbols, and so forth. The Word of God gives us a good indication that possessing idols can pollute the land and bring a curse upon it:
"Wherefore I poured my fury upon them for the blood that they had shed upon the land, and for their idols wherewith they had polluted it."-Ezekiel 36:18
"A drought is upon her waters; and they shall be dried up: for it is the land of graven images, and they are mad upon their idols."-Jeremiah 50:38
Demons may follow cursed objects, such as idols, occult items, Satanic jewelry, and even sinful photos and pornography. It is vital to rid a home or land of such items before dedicating it to the Lord and driving out the unclean spirits. Scripture clearly tells us that physical items can indeed carry spiritual value:
"Neither shalt thou bring an abomination into thine house, lest thou be a cursed thing like it: but thou shalt utterly detest it, and thou shalt utterly abhor it; for it is a cursed thing."-Deuteronomy 7:26
How do you cleanse a home or land?
The first step to cleansing a home, building, or property, is to get rid of any cursed items. If there are occult books, Ouija boards, crystal balls, New Age items, dream catchers or other items of pagan or occult origin, they need to be removed by the minister and burned at a neutral location. Just like we need to address entry points for the demonic in a person's life, it is also vital to remove the entry points to the demonic in our homes, buildings, and on property.
The next step is to go through each room, and pray over it, dedicating it to the Lord and asking the Holy Spirit to dwell there.
Finally, invoke the authority of Christ over the demons in the home, and command them to leave in Jesus' name. Go through each room, closet, nook and cranny, and command the unclean spirits residing there to come out in Jesus' name and to leave the property.