Does anyone know exactly where building 315 at Heathrow is? A friend is looking for a Barclay's ATM and I understand it is near Hatton Cross. Coming from Terminal 4, it seems reasonable take the 555 (etc) bus from T4 to Hatton Cross, go to the ATM, and then get on the Tube. Or at least that seems a much better idea than going to T5 from T4. Thanks.
(This is a follow-on to the closed thread at http://www.tripadvisor.com/ShowTopic-g186338-i17-k5414388-Getting_to_the_Barclay_s_ATM_in_Terminal_5_from_another_Term-London_England.html)