Cornwall Terrace, Regent‘s Park

For the renovation of eight propertiesinto ambassadorial residences,in one of London’s most prestigious locations, specifiers looked to a waterproofing system that would protect the historic and nationally prominent buildings to the utmost. They chose the market proven Sika 1 Pre-bagged Waterproofing System – a system that has provided undisputed protection for over 100 years.

Enjoying attractive views over Regent‘s Park, Cornwall Terrace was designed in 1812 for George, Prince of Wales, by John Nash, the famed architect who designed Trafalgar Square. Featuring elaborate stucco exteriors and grandiose designs, it is described as the “jewel in the crown” for its sumptuous construction and elegant planning. The magnificent ambassadorial mansions of Cornwall Terrace account for 8 Grade I listed homes, all of which are let on long leases.

Oakmayne Properties, working with award-winning architects Tate Hindle and English Heritage,completely redesigned and rebuilt the interiors and renovated the exteriors of the eight properties. Part of this work included the upgrading of its basements to provide more habitable living space for its residents.

The basement refurbishment project was overseen by main contractors Laing O’Rourke working with specialist contractor Aquarend. Providing their expertise to the waterproofing of the basements, they installed the Sika 1 Pre-bagged Waterproofing System, a system Aquarend has used on prestigious basement refurbishments in London many times over.

Sika 1 is a complete waterproofing system comprising of pre-bagged mortars, renders and screeds. Its impressive waterproofing attributes are a result of the innovative Sika 1 admixture. A colloidal silicate liquid, it swells on contact to water. This blocks the pores and capillaries of the system’s mortar and screed, providing a 100% watertight seal that keeps moisture out and ensures a basement free of water ingress and vapour. Once applied, the Sika 1 system is certified by the British Board of Agrément to last the lifetime of the building, ensuring future protection against water penetration – a perfect choice for buildings that are invaluable examples of Britain’s architectural heritage.

To ensure a totally waterproof seal, Aquarend cast a layer of Sika 1 Spritz Mortar over the basement‘s walls. This was followed by a second and third layer of Sika 1 Render and Finishing Mortar to the walls and vertical surfaces, whilst on the floors Sika 1 Spritz Mortar was topped with Sika 1 Screed Mortar.

Aquarend applied the system to the floors and walls of the basements throughout the 8 properties of Cornwall Terrace. This ensured a watertight envelope that would safeguard the buildings from any water damage. The basement spaces could then be refurbished to the requirements of Oakmayne Properties. To guarantee that the buildings were fully protected from subterranean water damage, Aquarend also applied Sika 1 to the under pavement vaults of the buildings.

Sika 1 meets the requirements of all three grades of waterproofing as outlined by BS8102: 2009, the Code of Practice for Protection of Below Ground Structures Against Water from the Ground. For the Cornwall Terrace basements, it needed to meet Grade 3, which ensures a dry structure with no moisture penetration. The system is so effective as a water barrier that not only is it used as a waterproofing membrane for basements, but its other uses include keeping water in – it is frequently used in swimming pools.

As well as BBA certification and meeting the stringent requirements of BS8102, Sika 1 is also supported by the Sika Waterproofing Registered Contractor Scheme, created to minimise risk for specifiers, main contractors and clients. It ensures all projects that require waterproofing benefit from the product’s proven performance as well as exceptional technical service from Sika’s team and first class installation from one of the company’s Registered Contractors.

The use of Sika 1 on the historic buildings at Cornwall Terrace is yet another case of it being relied upon to protect invaluable structures from water ingress and damage. With a long track record of success, it has been used on everything from tunnels and pavement vaults to the basements of commercial structures and prestigious heritage buildings. Certified to last as long as the lifetime of the building to which it is applied, it will protect the priceless properties at Cornwall Terrace for years into the future.

In addition to Sika 1, Sikafloor-264 was used on the garage and plant room floors to protect them from damage and ensure their integrity. A two-part, economic, solvent-free coloured epoxy resin, it is ideal for floor areas with medium to heavy usage. With excellent mechanical and chemical resistance, the slip resistant seal coat provided the finishing touches to the renovation work at the historic royal properties – as part of a range of comprehensive solutions from Sika that’s truly fit for a king.

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