Summary

Newton Specialist Contractor MJ Rooney undertook this extensive basement construction project beneath a period Georgian property in Tunbridge Wells, Kent.

Working alongside designers from Open Architecture and Croft Structural Engineers, the MJ Rooney team needed to carry out deep and large-scale excavations. This included significantly extending the existing basement beneath the period property and the rear garden, whilst retaining the original structure above with minimal disturbance.

Robust temporary works

Complex temporary works were designed to support the house on stilts during the excavation. Steel sheet piling was also essential to provide support around the site.

However, this wasn’t without its difficulties. The deep excavation works took place within the water table, and restricted site access was problematic for both the piling rig and during the new basement construction. Read on to see how the MJ Rooney team overcame these challenges.

Project scope

The large-scale new basement area was to include a swimming pool, leisure area, sauna, steam room, and cinema. All areas therefore needed to be completely dry, defined as a Grade 3 environment by BS 8102:2022. This required a waterproofing design that would account for the specific requirements of the site environment and the structure.

Solution

The primary solution was a full internal cavity drain system utilising Newton's comprehensive CDM System. But first MJ Rooney primed all concrete surfaces with CDM 906 Lime Inhibitor to prevent any ‘free lime’ from affecting the CDM System.

CDM 508 membrane was then installed to all walls to capture water. The CDM 520 eco Floor membrane also provided high volume drainage capacity across the floor.

A perimeter drainage system using CDM BaseDrain delivers any captured water to a Titan-Pro sump chamber with dual pumps for safe and reliable water removal.

Result

MJ Rooney’s meticulous approach ensured minimal disruption to the residence while delivering a high-quality, functional new basement in compliance with BS 8102. They also demonstrated their capability by supporting the installation with a 10-year insurance-backed guarantee.

Testimonial

“MJ Rooney were extremely professional in every respect. They completed a first-class construction job. I would recommend and use them again.”

Newton Specialist Contractors

Newton always recommends that its systems are installed by one of its nationwide network of Newton Specialist Basement Contractors (NSBCs). All members of the network adhere to strict criteria and are required to demonstrate quality workmanship, resulting in a meaningful scheme that provides unsurpassed technical excellence.

NSC's can also act as the waterproofing designer on your project, taking on the liability under their professional indemnity insurance. Finally, they also offer insurance backed guarantees to support their installations.