We can’t house our friends belongings anymore

They're in an absolutely shit situation. Sometimes people do make their situations worse by making unwise choices.

When you say but can’t help thinking they’ve brought this about themselves now as they were offered accommodation by the council and refused it and now I’d quite like my house back you CAN help thinking this. What you've written shows no compassion for their messy situation. You can want to get your space back without being uncompassionate.

Start the conversation about them finding somewhere else for their things. But also, don't lose sight of the fact they are in a very shit situation, so go easy on the judgement.

Of course YANBU OP. You've done your friends a massive favour by storing all their stuff for over a year now. I hope they had a very good reason for turning down the accommodation offer made to them by the council, but I think they were incredibly foolish to do so. I would give them a month's notice (no more!) to organise the rental of a storage unit and to move it all. They will likely play on your sympathies - they may even be nasty about it - but just remind them how much money you've saved them by them not having to have rented a storage unit for the past 12+ months. Unfortunately, as the old adage goes, no good deed goes unpunished.

They are taking the piss. You would be doing the right thing to say that you are struggling without the use of your property. You have done them a favour worth thousands of pounds of storage fees. Enough is enough.

No, get it out, all of it now. Use the money you were spending on rent to store it. That would do my head in after so long. They are taking the piss.

Are you willing to still store some of the stuff? Perhaps the garage? Storage is incredibly expensive so it would be kind to let them down gently. However having boxes in your bedroom is madness. All that needs to go.

Objectively, if they were paying rent before then they can afford storage as it will be cheaper and they have no housing costs.

I'd just say I couldn't keep it any longer as I'd envisaged it being a short term solution. However, now a year has passed, I'd tell them a storage unit would be better and that I'd be happy to help them move it.

I would also give them a cut off date (a couple of weeks before your real cut off), and hold very firmly to that real cut off date.

Id tell them they shouldnt of turned down the house, and they need to pay for a storage unit as you simply dont have the space to store it anymore and give them a date to get it gone by. They are taking the piss.

I was going to say you were unreasonable until I saw it has already been a year. I think you would not be unreasonable to tell them that you need your space back and if they want to keep the stuff, they will need to pay a self-storage place to keep it for them.