Thousands of families living in social housing are facing a cut in their benefits from April because they are seen to have too big a home.
The under-occupation penalty, dubbed "the bedroom tax", aims to encourage households to downsize if they have spare rooms, freeing up their properties for larger families.
But council house tenant Eddie Bird says the policy fails to take into consideration individual cases. His wife Shirley has terminal cancer, and weighing just five-and-a-half stone, needs her own room.
"Any form of movement on the bed and it affects my wife. She's in constant back pain," said Mr Bird. "There's no room for separate beds so I sleep in the box room."
They have been told they will lose nearly £14 a week in benefits.
"It's going to affect my wife's quality of life. We have a Motability car but if we can't afford to put petrol in it, we can't go on any day trips."
The Government hopes the policy will make better use of almost a million rooms that are not used and help reduce the £23bn housing benefit bill.
Communities Secretary Eric Pickles said: "We've put a fairly sizeable sum aside to be able to ensure that those kind of cases can be paid for.
"But the general idea that there has to be a limit on the amount of benefit that people receive I think is a correct one.
"And these are exactly the same kind of rules that have existed in the last few years in private rented (accommodation), so we are applying to public housing.
"If it was good enough for private renting, it's got to be good enough for public housing."
But critics question how you can penalise tenants for not moving somewhere smaller when there simply are not enough suitable sized properties available.
It is something the Coast and Country Housing Association has seen in South Teesside. They have 10,000 properties but only two one-bedroom apartments available.
Chief executive Iain Sim said: "We had the pasty tax last year - this is the nasty tax. This is hitting people directly who through no fault of their own are under-occupying the property that they live in.
"The cut in their benefit will range from 14% for one room up to 25% for two rooms. That's a loss in income of between £10 and £22 a week. That's a lot of money to take from people with very limited incomes."
The change is expected to affect 660,000 claimants.
Some households will be exempt if, for example, a non-resident carer for a disabled person helps at the home overnight.
But as Eddie and Shirley Bird are married they will not be eligible for this exemption. Their only hope is that they will qualify for financial assistance from a fund called the Discretionary Housing Payment scheme, but it is not guaranteed.