B&M – Pentwyn, Cardiff – Opening Hours & Store Details B&M Store is situated in an ideal position on Pentwyn Road, 3.33 miles north-east from the centre of Cardiff, in Pentwyn (right off Pentwyn of A48 / Eastern Avenue). This discount store is happy to serve patrons within the districts of Heath High Level, Llanrumney, St Mellons, St Edeyrn’s Village, Pentwyn, Llanishen, Heath Low Level and Llanedeyrn. Here you can find the specifics for B&M Pentwyn, Cardiff, including the operating times, place of business address details, customer feedback and further significant information.