I've been asked to put this on here as your NHM Facebook page have suggested it may be. I think it's a baby female Noble False Widow. I found it dropping down on a thread from a cupboard in my daughter's bedroom. I assume it's either a baby as it was about the size of my little finger nail, or soemthing else other than a false widow?
It fits the bill - has a light band at the top of the abdomen, the right legs, and a faint 'skull' on it too.
It's not an easy task to identify from these pics, but from the markings on the abdomen & the pedipalps, this looks more like Steatoda bipuncta, a false widow species but not one that is usually implicated in bite events. They are typically regarded as harmless.
It's more common name is the rabbit hutch spider, they are widespread accross most of England & much of Scotland.
Some of the sensationalised press reports have mistakenly linked stories attributed to Steatoda nobilis, with pictures of Steatoda bipuncta.