Welmar Mews, Clapham, London

How we got involved

Edge Structural Design provided specialist services for the conversion of a three-storey former London office building into apartments with extra weight-bearing capacity to allow for construction of an additional two storeys in the future. The project involved some complex and challenging factors.

We acted as consultants for the conversion of Welmar Mews in Clapham Park Road, Clapham, for Brantwood Design & Build, based in Greater Manchester, and London property developer Roland Duce.

The Clapham building dates from the early 2000s and now has three apartments across each of the three storeys.  Our services focused on structural strengthening work to provide additional support to floors and to minimise weight on the foundations. This was required to prepare the building for the future construction of fourth and fifth storeys.

What we did

We produced some foundation reports and drawings for the Welmar Mews redevelopment in late 2017 and the work was carried out during summer 2018.

The building and site may look straight-forward but, in fact, there were some complex factors and challenges in this project. These included the need for internal alterations including the removal of some existing load-bearing walls and the introduction of additional structural support, which was all completed within a tight schedule.

The client wanted the option to add two extra storeys on top of the three existing storeys, making it a five-storey building. To comply with building regulations, any building over four storeys must have a robust design for safety in the event of an accident.

For example, if there was a gas explosion that blew-out a wall in one part of a building, there must be secondary support for the structure including floor joists to prevent any damage spreading, which is known as disproportionate collapse.

We met those requirements by introducing steel columns and internal steel beams to the building, offering extra floor support. Furthermore, our plans for the proposed future fourth and fifth storeys use a light-weight steel frame design to keep loads on the existing floors to a minimum and address any challenges on the foundations.

Why we're proud of it

We specialise in working on challenging buildings and sites across the UK. For example, we have worked on developments on steep hillsides and uneven sites or with restricted access, poor drainage or complicated underground conditions.

For over 18 years, we have worked with Brantwood Design & Build on a number of projects in the north and south. Examples include building temporary, modular steel-framed multi-storey car parks at railway stations and hospitals and converting former church and textile mill buildings for new residential and commercial uses.