Barnsley Hospice staff have expressed their outrage after callous thieves stole lead from the roof of the facility.
A maintenance worker noticed lead flashing had been taken from two sides of the outbuilding which houses the laundrette behind the in-patient unit on Friday, August 24.
It has now been replaced with a non-lead alternative, at a cost to the charity of hundreds of pounds.
Julie Ferry, chief executive of Barnsley Hospice, said: “It’s despicable. There are people out there in the community doing so much to raise money to help us continue our care, and at the same time someone has decided to do this.
“I think I speak on behalf of all our staff, volunteers and supporters when I say how disappointed we are.”
HR director Alan Measham, who noticed the missing flashing from his office, added: “I’m disgusted. It’s difficult to put into words how I feel about someone stooping so low.”
Although the NHS provides the charity with an annual grant of £1.6 million, it still has to raise a further £2.2 million each year to care for patients and their families.
The theft has been reported to South Yorkshire Police.
Anyone with any information is urged to contact officers on 101, quoting crime reference number 14/124412/18.