Oh my goodness, what IS this noise?

That sounds scary!

This is a long shot - I don't suppose it is happening after you have flushed a toilet, is it? Air in the pipes can cause some strange noises as a cistern refills, and sound can travel through the pipes making it difficult to pinpoint where it is coming from.
As I said, it's a long shot, and in my experience tends to be more of a vibrating noise than a scraping one, but I thought I'd mention it just in case.

Thank you MamaCaz for that suggestion. I don't think it's linked to toilet flushing, but I will make a point of listening now

Was also wondering if it's something to do with the plumbing/pipes.

Maybe a hot water pipe for heating is expanding. Does it happen when the central heating is off? Otherwise, it could be a rat or squirrel as they're much noisier than mice!

I hope you haven't got mice again but if you had could it (sorry, this is a bit far out) be pulling something across the floor? Something for bedding perhaps?

I do feel for you. I kept hearing the sound of purring when I was in one room of our, at the time, very old house. Nobody believed me until a friend heard it and she suggested it was our recently deceased cat telling me everything was okay. That didn't help, as you may imagine. It turned out to be bees nesting in the wall. I hope you soon find a sensible reason for it.

When I get into bed I hear a noise like a ship's engine. Everything is switched off so can't find what it is. Actually I think this house was built by a sea captain.

If it's mice they must be wearing clogs !

Could be air in the pipes ?

That sounds like the kind of noise that my taps make sometimes when I turn the water on. A definite creaky sound. I can hear next doors sometimes. Could that be it ? It doesn’t happen every time and no idea why.

Could it be coming from your central heating system? We had similar sounding very random noises last winter and it turned out to be caused by a faulty valve in the boiler.

What would you think the mice are dragging across the floor gracesgran barbed wire? surely anything for a nest would be small amounts and soft not like wooden chairs dragging ?
Here’s a funny story for you Some years ago I got the fright of my life when I heard a whooshing sound only to find a hot water pipe had sprung a leak and boiling water was spurting out faster that the rate of knots I got over that (eventually) but one day I heard a whooshing noise coming from the bathroom I went into total panic mode heart thumping imaging boiling water going everywhere I tentatively opened the door to find my electric toothbrush had set itself off
If your house is oldish there’s all sorts of noises that often go unexplained
Hope you work it out my moneys on the pipes too I doubt it s anything to do with small animals or insects

Why not put a recorder and possibly CCTV camera in the offending room and see what can be seen, if anything.

The tape can then be played back to a central heating engineer or plumber so that they can hear what it sounds like and work out the cause.

If it is an old house sounds like pressure in water pipes vibrating against the floor boards or joists...

Kircubbin I hear that too. I'm convinced it's in my head.

I hate to say this but when this happened in an old house and something was clog dancing in the space between our bedroom ceiling and the floor above it turned out to be a rat which had climbed the outside drainpipe and got in through the holes in the eaves where the house martins nested.

I did say I hate to say it!

Sometimes our upstairs loo makes a loud noise after being flushed, the only way I can describe it is like a loud groaning or moaning, it's perhaps air in the pipes as the cistern refills or the pipes vibrating. This usually happens after I have settled comfortably in bed and the only option is to go and flush it again.

You don't have a new fridge, do you HurdyGurdy? Ours makes a very loud noise, apparently it is the gas in the pipes.

Is it a creaking, groaning kind of noise? If so, we get that with our radiators. Dh goes round and bleeds them all when I can't stand it any more.

We also have an extremely noisy fridge that makes loud cracks and bangs along with the usual compressor sounds. All our floors creak, too. It's a wonder anyone gets any sleep.

Can't give any advice but had a good laugh at all the tales!

We get pine martins in roof spaces here sometimes, they make a lot of noise. Just thought I'd cheer you up.

Our old fridge makes the most weird noises which echo illogically into different rooms. I can hear it in our bedroom which isn’t above the kitchen but not in the bathroom which is.

And like kircubbin I too get the ships engine room noise when in bed. I thought it was because the hollow bed base had a drum effect on any humming noise, but the drawers underneath are stuffed full. Once, when the engine room noise seemed louder and deeper, I tracked it down to the nearby pub ladies loo extractor fan! Noises travel differently on a still, quiet, summer’s night when the bedroom windows are open!

A friend had squirrels in the loft and between the floorboards - she said they made a lot of noise.

not really funny for you, I am giggling here, ghosties,,, but then if that was me, in the middle of the night, (I am alone save for my kitten/cat) I would be terrified..

have you got a cat? they are good at locating "noises"

btw I only believe in good ghosts. Truly!

It’s defo a Ghost.

Is your house joined to another next door? If it is, could your neighbour be using the lift space for an extra room, or just storage?