Small tortoiseshells in the house

borgadr

For the 3rd time in the last 4 weeks I've found a small tortoiseshell butterfly in the house.  They're always pretty docile - alive, but easy to handle without damaging and making no attempt to fly away. It's almost as if they're hibernating but it's surely far too early (the first time was late August).  They're not flying around when I find them, usually just perched on a wall. I take them outside and leave them somewhere sheltered. 

Anyone have an idea why they might be coming indoors?  Hibernating this early?

AnniD

Possibly. 
https://nurturing-nature.co.uk/gardening-for-wildlife/what-to-do-with-hibernating-butterflies-in-your-house/

WonkyWomble

This used to happen in a friend of mines house. It was a big old place and peacock butterflies used to try to over winter in her dining room bay window.... She used to leave a dish of sugar water in case they needed some nectar.