This is a harmless introduced spider in southern British Columbia that is frequently found around human habitation. It is easily identified because of its large size.
Wikipedia (2013) provides the following information on this species: "The Giant house spider is indigenous to northwestern Europe. However, it was unwittingly introduced to the Pacific Northwest of North America circa 1900 due to human activity and strongly increased in numbers for the last decade........Female body size can reach 18.5 millimetres (0.73 in) in length (making it the largest member of the family), with males having a slightly smaller body at around 12 to 15 millimetres (0.47 to 0.59 in) in length. The female leg span is typically around 45 millimetres (1.8 in). The leg span of the male is highly variable, with spans between 25 to 75 millimetres (0.98 to 2.95 in) being common."
Global: Palaearctic; introduced in Nearctic - Pacific Northwest and southern BC, scattered records in AB, SK, & NF. BC: Widespread and mostly synanthropic across southern BC, in natural habitats in southwest and south central localities. (Bennett et al. 2012)