Tonbridge Grammar School was originally established in 1905 and overtime the development of the 14 acre campus had become very segmented.

In order to strengthen the campus, a masterplan was developed in close consultation with school governors, staff, pupils, parents, planners and neighbours in order to deliver a compact and uncomplicated site layout.

To facilitate the redevelopment plans, the existing entrance was repositioned to enable complete remodelling. The main works were then carried out in phases whilst the school remained operational.

Phase 1 of the works delivered a new three-storey classroom block and sports hall, replacing a number of temporary classrooms. The new building, which is of steel frame construction with brick and blockwork external walls, accommodates 39 state-of-the-art classrooms with large storage cupboards, offices, resource rooms and a new library known as the LOGIC, together with an indoor sports facility incorporating drama and dance classrooms and changing rooms. All classrooms have tempered ventilation systems linked to the gas fired heating installation. There are also disabled toilets on every floor and lift access throughout the building. New netball courts and tennis courts have also been provided along with a large car park including seven dedicated disabled spaces.

Phase 2 consisted of the refurbishment and remodelling of the main building after a large part of the original school building had been demolished. The new layout incorporates art and music classrooms as well as a cookery suite. Additionally, the original gymnasium was converted into a dining hall with an adjacent sixth form café.

calfordseaden was appointed as Client Representative and Site Inspector for the provision of the IBarn, a new sixth form centre, using modular construction methods under phase 3. The centre provides flexible teaching spaces suitable for the International Baccalaureate, including 3 classrooms, a conference room, lecture theatre, offices and a new café. The rear of the building has seen the construction of new changing facilities for outdoor sport and fitness.

The spaces previously occupied by the sixth form have been redesigned to expand the current music department which now features nine sound proof practice rooms and a recording studio.