Hi, judging from the picture as it's not the most clearest I would suggest that it is Amaurobius similis
Also known as the lace web spider. Where I live the local community have gone nuts over these spiders mistaking them for the false widow due to their shape size and colour. But I have hundreds of these lace web spiders on the outside of my house.
You would normally find these spiders outside on the window. Or under any edge on the outside of your home. Usually if you see one you will see quite a few more. The males are more active in the autumn as they are looking for mates so if you look at the tops of your windows outside you should see a few of them with their nests.