Wandsworth Council are purchasing two houses which have lain empty for several years.
Councillors voted to authorise compulsory purchase orders on the two properties in Shelgate Road, Battersea, yesterday.
The houses, owned by two brothers, are uninhabitable with no central heating, bathing or cooking facilities.
It is estimated it will cost £50,000 to bring them to a reasonable living standard, with brothers and their family owning a further six properties including another in Shelgate Road.
One house which has five bedrooms has been empty since 1998, while the other has four bedrooms and has been unoccupied since 1993.
A report found the owners failed to meet deadlines for repair work and had argued they were being lived in, despite the lack of facilities.
The council will now make offers to purchase the homes by agreement and will pursue compulsory purchase orders (CPO) if this fails.
A CPO gives the council the power to obtain the buildings, without the permission of the owner.
Councillors Paul Ellis, cabinet member for housing, said: "It is a shame that we have to exercise these powers, and we do not do so lightly, but in the midst of a serious housing shortage across London, these two homes have stood empty for long enough.
"We have been extremely patient and given the owners every possible chance to act, but unfortunately they have not done so, and as a result there are two large family-sized houses in this street that are totally uninhabitable.
"We cannot stand idly by while these properties blight the area. We will now work swiftly to ensure these homes are brought back into use."