K1 Knightsbridge

• Client: Skanska
• Sector: Mixed-use scheme
• Services: Firestopping & Commercial Decorating
• Region: Royal Borough of Kensington and Chelsea
• Size: 340,000 sp. ft
• Project Value: £160 million

Project Overview

The K1 Knightsbridge project was a substantial redevelopment in one of the most prestigious and valuable locations in London.  

When the £160million project was completed in 2022, it delivered a mixed-use space covering 340,000 square feet. This comprised high-end retail and office facilities, 29 luxury apartments and a new rooftop restaurant.  

There were several serious challenges associated with the successful delivery of this flagship project. One was to maintain the site’s historic facades in this high-visibility location close to world-famous stores like Harrods and Harvey Nichols.  

Another was that the new development sat directly over Knightsbridge station, on London Underground’s Piccadilly Line. Anti-vibration springs were used in the basement to prevent any tremors being transmitted through the building during construction.  

These needed to be fire protected for 120 minutes, while allowing for movement of the bearings.  

Skanska, the company contracted by the Olayan Group, the site’s owners, to carry out the development, commissioned Sentinel to deliver the firestopping capability on the anti-vibration springs. 

We were also asked to carry out a wide variety of commercial decorating at the site, one of the most valuable pieces of real estate in the capital. The work we delivered has bolstered our reputation as London’s favourite specialist decorating and fire protection sub-contractor.   

Project Brief

This was a project full of challenges both above and below ground. For Sentinel, the presence of an underground line directly beneath the site was a test of our passive fire protection and commercial decorating ingenuity and experience.  

The basement structure of the new development was kept separate from the rest of the building structure using anti-vibration springs. This was so that any vibrations from the tube lines would not be transmitted through the floors being redeveloped above.  

These springs had to be fire protected for 120 minutes – a high level of resistance – while still allowing for movement of the bearings.  

As London’s favourite specialist decorating and fire protection sub-contractor, we’re proud of our ability to find a solution to overcome any obstacle. It’s a privilege to be able to report that we rose to the challenge in this instance.  

As well as the passive fire protection work in the basement area of the new development, Sentinel was also invited to deliver a variety of commercial decorating throughout. We were involved in the decoration of the retail areas, offices, residential units and the rooftop restaurant. 

It was a pleasure for our teams to be involved with a high-profile project like this, in such a distinguished location, and to demonstrate why we are known as the UK’s preferred specialist decorating contractor.  

Challenges / Solution

K1 Knightsbridge turned out to be a stunning development – and one of its most impressive elements is the firestopping delivered by Sentinel. 

This was a project that needed an innovative solution to the problem of creating a high level of fire protection for anti-vibration springs that were designed to separate the basement from the rest of the building. 

We worked closely with Promat Limited to develop a Fire Rated Board system. This was mechanically fixed to the soffit of the floor slab encasing the anti-vibration bearings, while allowing the movement tolerance to be accommodated.  

Vibration is a common problem when you are building above underground transport systems. The creative solution we used in this case has since been rolled out on several other projects.  

We were also able to use our extensive experience as specialist decorators by working on a variety of surfaces in units throughout the development. The paints and colours we used were as follows: 

• Walls and ceilings: Diamond Matt 9016 
• Woodwork: Diamond Eggshell 9016 
• Floor paint: Flowcrete SF41 anti slip, in mid grey, light grey and dark grey 
• Line marking paint: Flowcrete line marking paint in yellow, white and black 

The Result

It was a pleasure to be involved in such a prestigious project, and to be able to showcase Sentinel’s expertise in commercial decorating and passive fire protection in a high-end setting in the heart of London.  

We handed over on time after completing the commercial decorating work throughout a development that has delivered a revitalised environment for local residents and visitors. 

We were delighted that the innovative solution to the challenge of fireproofing basement areas near to underground transport was so successful that it has been used on many other projects since the completion of K1 Knightsbridge. 

The presence of Knightsbridge station, and the busy Piccadilly Line that runs through it, added considerably to the challenge of redeveloping this historic site. We were able to deliver our passive fire protection solution with no impact on the operation of the station or on the service through it.  

Technically, this was an extremely complex project. But the people who use this corner of Knightsbridge now have a prestigious new development to enjoy, as well as wider pavements and a new step-free entrance to the tube station.  

We are proud to have made a significant and innovative contribution to a project that has, we believe, enriched the heritage of the area while respecting its history.