A single document was found in a room adjacent to the garage and no documents were found in the Bidens' Rehoboth Beach home, White House Special Counsel Richard Sauber said in a statement.
The administration is "fully co-operating" to ensure that the records are handled properly, he said.
The announcement comes days after it was disclosed that sensitive documents were also found at the office of Biden's former Washington DC institute.
Sauber said after the initial documents were found by Biden's personal lawyers, they examined other locations where records might have been shipped after Biden left the vice presidency in 2017.
The White House did not say when the subsequent search began or when the additional documents were found, only that the search was completed on Wednesday evening.
Sauber said the Department of Justice was "immediately notified" after the documents were located and that department lawyers took custody of the records.
Regardless of the Justice Department review, the revelation that Biden potentially mishandled classified or presidential records is proving to be a political headache for Biden, who said former president Donald Trump was "irresponsible" for keeping hundreds of such records at his private club in Florida.
Earlier this week, the White House confirmed that the department was reviewing "a small number of documents with classified markings" found at the Washington DC office.
Biden's lawyers had discovered the material at the offices of the Penn Biden Center and then immediately called the National Archives about the discovery, the White House said.
Biden kept an office there after he left the vice presidency in 2017 until shortly before he launched his Democratic presidential campaign in 2019.
The revelation that additional classified documents were uncovered by Biden's team came hours after White House press secretary Karine Jean-Pierre dodged questions about Biden's handling of classified information and the West Wing's management of the discovery.
She had said on Wednesday that the White House was committed to handling the matter in the "right way," pointing to Biden's personal lawyers' immediate notification of the National Archives.
But she refused to say when Biden himself had been briefed, whether there were any more classified documents potentially located at other unauthorised locations, and why the White House waited more than two months to reveal the discovery of the initial batch of documents.
They were found on November 2, days before the midterm elections.
"As my colleagues in the Counsel have stated and said to all of you yesterday, this is an ongoing process under the review of the Department of Justice. So we are going to be limited on what we can say here," Jean-Pierre said.
with AP
