Hi, my name is Bot22!

There's no such thing as half a spare room. If you live in social housing a spare bedroom is a spare bedroom. It doesn't matter what size it is, if it's a bedroom it's counted.

https://www.citizensadvice.org.uk/benefits/help-if-on-a-low-income/housing-benefit/how-an-extra-bedroom-affects-your-housing-benefit/check-if-a-room-counts-as-an-extra-bedroom-for-housing-benefit/

Are you claiming any disability benefits such as daily living PIP or mid/high rate care DLA? if so and you need regular overnight care it maybe possible to claim for overnight care and this would mean an extra bedroom.

That act states that a room smaller than 50 square feet can't be used for sleeping in.

So a room of 55 square feet is perfectly legal as a bedroom.