External alterations comprising the lowering of sills of two windows in the western facade of Thames House and installation of two doors to provide access from the seventh floor level for the new terrace amenity space.

External alterations at seventh floor roof level comprising: (i) lowering of sills of two windows in western facade of Thames House to create door openings providing access from adjoining lift core and means of escape to stair core; (ii) consolidation of existing plant behind new 1800mm plant enclosure; (iii) creation of new rooftop amenity terrace incorporating new seating, planting and 1100mm balustrades; (iv) creation of means of escape across roof with new stair to the sixth floor terrace; and (v) removal of existing balustrade and existing BMU track; and associated works.