I done a lift shaft once in Manchester,oxford rd.wouldnt want to do one again,very dangerous,when we put it up it was eight ft by six ft,they put two extraction pipes in,side by side,all way up.we could only just get past them to get up,no access from top,as it had some fancy tower on top.if there had been a fire ,or owt like that,it would have been like being in a chimney.no ladders,as the longest we could get in was ten foots.what im saying is,be sure you know what your getting into.it was about seven or eight lifts high.