Converting this courthouse building into a boutique hotel required careful planning together with a sympathetic specification. The building’s Grade II status required preservation of the original single pane windows. Selectaglaze was engaged to address the challenge of transforming Victorian primary windows into thermally and acoustically efficient windows fit for the twenty first century. The project required the treatment of a vast range of different styles of windows. A total of 106 secondary glazing units were designed, made and installed. Styles ranged from curved, circular, raked openings as well as a beautiful double floor height feature window which was 5.287m high and 2.045m in width. The circular windows on the top floor of the hotel required particular care and a bespoke fixing system to meet the functionality requirements of the client. All units were finished in white to match to original frames. Careful attention was paid at the design stage to ensure that the original site lines of all the windows were retained.  Old Street Courthouse Hotel now benefits from secondary glazing units that exclude draughts and retain up to 50% more heat. In addition the windows dramatically reduce noise ingress from the busy street outside.