Transport for London (TfL) is actively exploring opportunities to maximise its land for the development of new homes. Ramboll was commissioned to update a feasibility study using in-house parametric optioneering tools. Multiple design options were provided for building over the challenging and constrained site of a live station.
The development opportunity at Finchley Central
TfL land around and above the two Northern Line stations in Zone 4 at Finchley Central and High Barnet was explored during the five-month commission. The study reported on the technical viability of developing in this area, including consideration of options for development over and adjacent to the tracks and station buildings and site constraints.
Complex rail-engineering challenges and constraints
This development opportunity presented a number of complex engineering and logistical challenges:
- The busy Northern Line station handles 7.2 million passenger visits per annum.
- The site marks the junction between the High Barnet and Mill Hill East branches of the line and consequently operates significant rail infrastructure and assets.
- The site has a complex topography, contains multiple utilities and is crossed by the A598 (Finchley Road)
- Known engineering constraints, such as the tracks, piling capacities, maximum bridge spans.
SiteSolve offered valuable solutions
Ramboll used the parametric design tool SiteSolve to facilitate the rapid exploration of potential solutions. The site constraints were factored in to SiteSolve, and computational design options were modelled with the client, architects and other stakeholders in the same room.
SiteSolve’s open-door approach is transforming the way we share early stage design options in the built environment. By engaging and collaborating with all delivery partners at the same time, we can deliver project outcomes more efficiently in a compressed programme period.
At Finchley Central, this approach enabled parties to visualise the impact of different development options on areas of the challenging site, which would otherwise have taken weeks to explore and share.
SiteSolve offered evidence that by spanning bridge decks over the rail tracks without intermediate support, we could potentially generate 5000m2 additional viable development area than previously expected. Furthermore, we showed that adopting this option would remove the need to construct foundations in the highly constrained zone between the railway tracks, which would:
- Contribute significant savings in site construction costs
- Significantly reduce safety hazards and
- Mitigate expensive rail disruption.
Our work on this project prompted Martin Teodorczyk, Development Manager at TfL to comment: “Clear thinking, logical and robust solutions, commercially aware while knowledgeable about constraints and challenges.”