Recursion is used to describe the relationship between the objects and the object defined is being defined within its own definition. Recursion is a method of defining functions in which the function being defined is applied within its own definition. The term is also used more generally to describe a process of repeating objects in a self-similar way. Broadly speaking recursion concerns the way in which events continually enter into, become entangled with, and then re-enter the universe they describe. Recursion is about participants relationship with our environment.

The recursive handrail was developed for use with the building energy management system [BEMS] in the Portland square building at the University of Plymouth. The concept for the handrail is about the recursion of form with a real-time feed from the temperature sensors in the building. To achieve this an existing handrail in atrium B of Portland square building is chosen as the site. There are six smart temperature sensors around the existing handrail. The temperature real-time feed is used to assimilate slivers of the recursive handrail. As a section of the new handrail is constructed this new handrail replaces the existing section of the handrail. Each day from dawn till dusk data is collated and a unique form for the section of the handrail is defined. From dusk till dawn one new section of the handrail is printed using a rapid prototyping machine. Thus each day the handrail evolves in its shape. The new section of the handrail has a smart heating element placed inside its centre. The temperature from the handrail is linked to the amount public traffic in the building, i.e. if there are many people walking up Atrium B staircase, the temperature will be low, if there are few or very little public traffic the temperature will be high. The heat produced affects the readings on the smart sensors, thus the participant in the space becomes involved in the relationship of defining the shape of the handrail through the relationship with the building. The handrail is constantly being redefined and reshaped by the changing collation of the changing temperature sensors placed in the building, since the participant in the building affects the changes in the smart temperature sensors, in effect the participant is slowly adapting and augmenting the building through occupation.