City of London Street Accessibility Tool (CoLSAT)

Image of a spreadsheet with a list of street features down the left hand side, with drop down menus to configure each one, and symbols representing different types of disabled street user along the top. Where the columns and rows intersect cells are highlighted in are red, orange and green

The City of London Street Accessibility Tool is a spreadsheet based design aid that allows users to model an existing or proposed street and quickly identify its likely impact on different groups of disabled people, representing a very wide spectrum of needs. It is based on in depth interviews with 34 disabled people. The tool identifies specific groups of disabled people, for example ‘Long cane users’ or ‘People with a walking impairment who do not use a mobility aid’, who will be positively or negatively impacted by particular street features and surfaces relevant direct quotes from the research to contextualise issues highlighted, and communicate the lived experience of the disabled people most affected by a design decision to the designer at the point when it will be most useful and impactful.

Image of a spreadsheet with a list of street features down the left hand side, with drop down menus to configure each one, and symbols representing different types of disabled street user along the top. Where the columns and rows intersect cells are highlighted in are red, orange and green. The image is animated and shows the user changing the configuration of one of the features and the highlighting changing colour. When the user hovers next to one of the highlighted cells some quotes pop up describing how participants in the relevant segment feel about that feature


Working in partnership with public realm and transport design practice Urban Movement we won a tender from the City of London Corporation (the local authority responsible for the ‘square mile’ within the historic city walls of London). The City were initially looking to develop a street accessibility standard based on primary research with disabled people and wanted tenderers to propose a methodology for doing this.

Reflecting on the numerous shadowing projects we had worked on previously, I felt like we had always done a fairly good job of collecting the lived experiences of the disabled people who had been generous enough to participate in the research, but we had done a less good job of communicating what we had found out in a way that was straightforward to act upon for the people who actually design our streets. We had tried reports in various formats as well as online ‘insight banks’ with overlapping tag structures and video clips showing participants highlighting and explaining issues, but they always seemed to be filed away and the people doing design kept on doing what they had always done.

The brief from The City seemed like a great opportunity to make a better job of this most impactful part of a research project, and also to do a piece of research with a sample that was large enough to attempt to systematically cover the full diversity of needs amongst disabled street users. It was exactly that engagement that the city were looking for. They were also asking questions, for example about how to resolve conflicts between the needs of different groups of street users, that we are also very interested in trying to answer.


The methodology we proposed was based on acknowledging two key facts about accessibility:

  1. Whilst some accessibility issues are a strict inaccessible/accessible binary this is the minority, with most issues disabled people face with street design falling in the space between these two poles, with increasing levels of frustration and difficulty ending up with exclusion. We used the framework proposed by researchers at Philips US and quoted in the Cambridge Inclusive Design Toolkit to explain this.Stylised graph with Users on the y-axis and Product Experience on the x-axis. From left to right the line begins horizontal, with the area under it shaded green and labelled 'Finds Easy' moving further right the line drops down slightly with the area underneath shaded orange and labelled 'Frustrated', further right the line starts to drop more progressively with the area under shaded light red and labelled 'Has Difficulty', furthest to the right the line is almost at the x-axis, the area under is shaded dark red and labelled 'Excluded'
  2. For a person to make a journey, every link in the ‘journey chain’ must be accessible for them. For a street this means it is only as accessible as its least accessible element, so to fully analyse the accessibility of a street you need to break it down into its constituent features and attributes, and analyse the accessibility of each of them.

These two tenants meant we created a methodology that broke down the street into its constituent features and asked disabled people to quantify how those features affected them on the spectrum between ‘helpful’ and ‘excluding in any circumstances’. In order to cover the full spectrum of street design features in context a walking route was identified that included examples of different types of street and street features found within the city.


Initially on-street shadowing was planned as the main research method, with participants undertaking guided walks on the walking route as part of a semi-structured interview. Two pilot walks were undertaken but the COVID 19 pandemic intervened and the rest of the interviews were conducted remotely over video call, with participants commenting on a video of the walkthrough. Participants with sight loss were provided with an audio described version of the video as well as a box of tactile models representing specific layouts and features, such as tactile paving arrangements, crossing designs and bus stop positions.

The in-context open-collection phase of the interview was followed by a second part where interviewer and participant worked through an index of street features and their possible configurations with participants assigning each configuration a score (from 0 to 4) based on how it would be likely to impact their use of a street. At the end of the interview participants were asked if there was anything important that had not been covered in the index, with suggestions added and assigned a neutral score for previous participants. At At the end of the process this index ended up comprised 44 street features and attributes, each with between two and eight possible configurations.

In order to represent the fullest diversity of disabled street users, within the limited resources of the project, participants were recruited within 12 needs segments. These were created based on the similarities and differences in the experiences and needs of participants in previous shadowing projects. The scores used in the tool for each segment were established by aggregating scores across participants in that segment.


The tool is hosted on the City of London website and can be used by anyone seeking to assess the accessibility of a street design or identify key accessibility issues on an existing street network.

It has been in use by City of London highways officers for over a year and has become an established part of their design process, being used on every project from small traffic calming features to whole area schemes. It was used extensively on the redevelopment of Bank Junction (one of the largest public realm schemes undertaken in London at the time) and resulted in the delineation of previously undeliniated level surfaces at traffic tables, the retention of 60mm kerbs in areas which would have had undeliniated level surfaces or 25mm kerbs, additional seating throughout the scheme and increased spacing between security bollards.



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