Luxury Basement Extension, South London

Considering the large size of the basement area and its proximity to the River Thames, Newton Specialist Contractor Stonehouse were called in to provide a complete waterproofing system for the structure.

The Project
At this private property in South London, the plan was to build a new basement extending below the entire footprint of the house and into the rear garden, incorporating a swimming pool, recreational spaces and wine cellar.

However, considering the close proximity to the River Thames and the high-water table, Newton Specialist Contractor Stonehouse were called in to provide a complete waterproofing system for the entire structure.

The Solution
Considering the size of the basement area, the high-water table, the geographical location close to the River Thames, and the fact that the structure was created using underpinning, the risk of water penetration in this basement was extremely high. Stonehouse therefore recommended the most failsafe solution, the Newton CDM System.

Firstly, they installed Newton 508 membrane to all internal walls, as well as the floor, using Newton’s ancillary products to fix the membrane securely and seal the system. Drainage channels were also created using Newton Basedrain, feeding to a sump chamber containing two NP750 pumps, a higher capacity model capable of dealing with large volumes of water.

Finally, where the basement extended beyond the footprint of the house, a liquid waterproofing membrane was used on the new external roof.

The Result
Stonehouse are one of Newton’s oldest and most experienced specialist contractors, and they showed their expertise here by delivering a dry, safe basement for the client that could then be transformed into a beautiful new part of their home. Furthermore, the installation was backed by Stonehouse’s 10-year guarantee, for complete peace of mind.

“At every phase of this project, we were aware of the presence of the River Thames. Water permeated throughout the excavation and it was essential that the waterproofing of this substantial basement which extends beyond the footprint under the garden was reliable and robust. Stonehouse has worked on over 50 projects with this architect, always using Newton products with our work matching in both quality and craftsmanship.” − Graham Stone, Managing Director, Stonehouse

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