A SPOTLIGHT ON | A Super-Prime Country Residence
Over the last five years, Knowles have operated multiple sites located throughout the Home Counties, in addition to our main base of London, managed by Knowles’ Country Division.
With projects located in Berkshire, Surrey, Wiltshire, The Cotswolds and more, we have utilised and homed in on our decades of experience, alongside a focus on innovation and value engineering gained and achieved in London, to offer all our clients across the UK, the same dynamic and agile service that we are recognsied for in London, in these Home County locations.
In this blog, we dive a bit deeper into one of our super-prime schemes in Surrey where Knowles are working as Principal Contractor.
Located in one of the most exclusive villages in Surrey, once built this private residence will stand as a magnificent four-storey home, which features everything a house of this stature requires – including, but not limited to a swimming pool wing, guest houses, staff accommodation, private car storage, gate lodges and other ancillary building – all of which will be designed with stunning architectural features. These features include a projecting pediment on stone pilasters, classic sash windows with stone surrounds and a classic no-Georgian symmetrical appearance with a Palladian influence.
As Principal Contractor, Knowles’ scope of works on the project includes the excavation of a 35,000 sq/ft basement and a 38,000 sq/ft superstructure – along with other essential works including landscaping and building of required access roads.
A notable feature of this project is the beautiful French limestone stone that has been specially sourced from the Tonnerre basin in Massangis, Burgundy. Supplied and manufactured by HÉRÈS, 800 cubic meters of limestone will clad the entire exterior of the 38,000 sq/ft superstructure. This stone has been used on spectacular monuments including the pillars by the Eiffel Tower, originating from one of the most beautiful quarries in France.
Sitting on an impressive 15 acres, with an anticipated construction completion date of Spring 2024, the residence will stand as one of the UK’s most prestigious country-houses.
However, with a project of this magnitude, challenges are to be expected. We sat down with Project Manager, Nic Goulbourn to find out about what challenges has faced on this project, how he overcame them, what he finds most interesting about the project and what he believes is the key to delivering a project of this scale.
What challenges have you experience so far? And how did you overcome them?
Our basement excavation was carried out below the water table. Dewatering is used on civil engineering and construction projects to enable excavations to go below the groundwater level.
We used dewatering methods that involves the temporary lowering of groundwater level to below an excavation level to enable an excavation to be undertaken in stable ground conditions. The water from the ground was then recirculated back into the ground through discharge wells installed in a separate location of site. The dewatering was installed onto perimeter sheet piling around the perimeter of site until the Basement concrete box was fully formed.
The Basement box was sitting on Tension Piles Tension piles which had to be designed to anchor the concrete box to resist uplift forces that might otherwise cause it to be extracted from the ground.
During some of the deeper excavations (lift pits, chambers etc.) the ground water became an issue, so we had to locally dewater the excavations to allow pits to be constructed.
What has been your favourite part of the project so far?
The programme for the ground works and frame was aggressive but we have managed to stay ahead of programme even with challenging ground conditions. The team have all stepped up to the challenge and the hard work has paid off.
What do you believe is the key to delivering a successful project of this scale?
Collaboration as this is the key to a successful project. Collaboration encourages teamwork, it stimulates information sharing, helps improves communication amongst project team members and most importantly, improves the quality and efficiency of the project. The collaboration between Knowles, our subcontractors and the Client Team has been great to date.
What did you find interesting about his project?
The scale of the project is huge. The Main House is circa 60,000 sq ft with a further 9,000 sq ft of ancillary buildings. It’s the biggest property I have personally worked on and I’m looking forward to seeing it finished.
What is the most complex aspect of building a basement of this size?
Other than ground water, we have had to excavate and remove 4,000 muck away lorries from site through narrow village roads. On some days we had over 100 lorries visiting site to keep up with the excavation programme. This took a lot of coordination on site to keep it efficient and safe.
