The Oast House project is a 350 unit multi-storey residential development for Spelthorne Borough Council which the council will retain and rent out. The project includes two towers up to 18 storeys and the refurbishment of a grade 2 listed Oast House to form a community theatre. At concept stage the use of modern methods of construction (MMC) are being considered including light gauge steel (LGS), volumetric solutions and cross laminated timber (CLT). These are being evaluated against a traditional reinforced concrete frame in terms of the relative values of embodied carbon, cost of construction and in use, procurement and construction programme, and future flexibility. The site is constrained by adjacent buildings and a main railway line and therefore construction logistics are also an important consideration.