Clark Hall, which was run by GT Care Ltd, was described as unsafe by the health watchdog and its management was criticised for a number of failings.
The service, which was offering care to 12 people at the time of an inspection by the Care Quality Commission (CQC) last December, had not informed the regulator of a change of address as required, a report said.
Although Clark Hall staff were praised for their caring attitude to patients, some relatives said communication with the company was not good.
In their report, which was published on May 7, inspectors said: "We arrived at the (registered) location (for the service) and found this to be an empty premises with no evidence of the service being run from here.
"We saw a skip outside with various discarded items including office furniture and some documentation.
"The registered manager brought some documentation for us to look at which related to one of the people who received personal care from the service.
"When we announced the inspection by telephone the registered provider told us there was only one person who received personal care.
"At the inspection we discussed this further with the registered manager, they still told us there was only one person who received personal care. However, when we questioned this further we were told more people received personal care."
When inspectors asked for more information relating to complaints, staff rotas and other care documents, the service told them they'd been "emptied from the location" for "confidentiality" reasons.
The report added: "They acknowledged sensitive information should not have been in the skip."
Employees were credited with promoting people's dignity and one relative said, "I can't rate the caring staff highly enough".
But inspectors added: "One person we spoke with told us they did not always feel safe because the staff did not reliably come on time.
"The registered manager told us staff were reliable in their support for people, but there were no systems in place to evidence this.
"Relatives we spoke with gave mixed views about whether the service was safe.
"Some relatives told us their family members felt safe when cared for by staff.
"Other relatives told us staff did not always understand the individual or complex risks to their family members."
Stanley-based GT Care Ltd was contacted for comment but has not responded.
The CQC told the Local Democracy Reporting Service that the Clark Hall service has been closed by the company.
Although its registered address was given as Aberford Road, it is not known whether it was being run from here at the time of its closure.
Local Democracy Reporting Service