The Milton Gate project at 60 Chiswell Street has been designed by Allford Hall Monaghan Morris and would raise the floor space by nearly 50% to around 290,000 sq ft.

The existing building, characterised by a green glass facade, is presently occupied by a law firm and will become vacant in 2025.

The original façade design used one conventional skin of double-glazed units on the interior and a third, outward-facing skin of green-tinted glass.

The bottom five floors of structural frame will be retained with the three floors forming the upper roof of the old building demolished to raise the mass of the building to 11 floors.

It will be designed to be net-zero carbon, achieving a minimum of BREEAM ‘Excellent’ and NABERS UK rating of 5 stars.

The professional team includes: structural/civil engineer, Heyne Tillett Steel; mechanical and ventilation engineer, Chapmans.