Fraser Bond are the leading lettings and property management agents for 1 Undershaft - London EC3P. 1 Undershaft is an office development in the City of London EC3. History 2016 December - planning permission granted. Eric Parry Architects have designed a new 73-storey office building to replace the current one. The planning application was submitted in January 2016. Public consultation 7-9th December 2015. The design for the new tower has been commissioned by Singapore-based Aroland Holdings. The existing 23-storey St Helen's tower completed in 1969 was designed by GMW Architects. Also known.