The public works minister said R5 million a month was spent on 108 vacant properties.
Public Works Minister Thulas Nxesi addressed Sadtu members in Khayelitsha on Friday.
Minister Thulas Nxesi says opposition parties are using the Nkandla report to campaign for the elections.
The Public Works Dept refuses to provide information on who signed off on the Nkandla upgrades.
The DA is trying to determine whether government is paying for electricity at Nkandla.
Opposition parties say govt’s Nkandla report is just a smokescreen to protect the president.