Client: Capital & Counties
Location: Covent Garden, London
Completion Date: July 2017
Other Team Members: Biotecture
Images & Video courtesy of Biotecture
The project was centred around the over-cladding of an existing masonry façade with a hydroponic living wall. Biotecture instructed Evolve to provide structural engineering advice to enable the installation. Our scope included checking the adequacy of the existing structure to be able to bear the additional load associated with the new vertical garden and to design the support frame. The building, which is owned by Capital & Counties, is located directly outside of Covent Garden Underground Station. The aim of the project was to make the property a feature of this historical area.
Since its completion, a secondary design was undertaken to enable the addition of a large red ribbon, as part of Westminster’s Christmas decoration plans. The fitting of the bow required the removal of existing planter panels and the introduction of a new ‘spider bracket’ support that would utilise the Evolve-designed steel frame behind, to hang a new ladder support system. The brief required that the additional brackets should be easy to fit on site. They would also need to be removed and reused each year.
The key challenge with this project was developing a solution that allowed us to efficiently connect into the existing structural frame.
Regal House has a structural layout that means there are no columns along the edge of the floor plate at the levels we were concerned with; this is due to the slab cantilevering out a short distance to form the building footprint. Because of this, the vertical spacing of supports was limited to approximately three metres, which is dictated by the internal floor levels. The large spacing of fixing points lent itself to a lightweight steel framing system that allowed Biotecture to affix its backing board and support any plant boxes.
Additionally, the slab edge is notched along its entirety meaning it was only possible to fix into the very toe of the nib with one row of bolts. In order to deal with the associated moments created by the cantilevered framing system and plant boxes, the wall plate would be relied upon with the pivot for rotation being extremely close to the supporting bolt. To overcome this and provide sufficient resistance to the moments, the number of brackets had to be increased, particularly in areas that have large overhanging plant boxes.
This project was an interesting one for Evolve, especially given the environmental benefits provided by this ‘living’ structure with its ability to improve air quality, capture pollutants and increase biodiversity. It is also wonderful to see it on display for the public to enjoy.