Waterproofing a Listed Building Extension

Summary

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  Newton 508 cavity drain membrane installed to the new extension walls

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  65mm of screed applied as a finish to the floor

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  The main room of the extension has been made completely dry and habitable by the installation of a full System 500 cavity drainage membrane system

Newton System 500 cavity drain waterproofing installed to a new-build extension of this Grade II Mansion, with two Newton Titan-Pro Chambers including twin NP400 pumps to manage and remove ingressing water. Successfully waterproofed by Specialist Contractor AP Gooch Basement Waterproofing.

The Project

The rural countryside near the market town of Swaffham, Norfolk, hosts Pickenham Hall, a Grade II Listed mansion. The principle building is a two-storey Neo-Georgian structure from the early 20th Century. Newton Specialist Contractor AP Gooch Basement Waterproofing designed and installed an effective waterproofing solution for a 3,000 square-foot extension to the mansion, which Kier Construction was undertaking.

The Solution

AP Gooch installed the full Newton System 500 cavity drainage system in order to manage and remove any ingressing water. The main element of the system consisted of the 8mm deep Newton 508 membrane. This was installed to the walls and floors of the large basement area.

Newton System 500 is a fully maintainable waterproofing solution. Therefore, it complies with the requirements of BS 8102:Below-Grounditish Standard Code of Practice for the Protection of Below-Ground Structures Against Water from the Ground.

The floor build-up included a structural slab topped with 50 mm of closed-cell insulation, the Newton 508 membrane, and a 65 mm screed. As part of the system, installers fitted Newton Basedrain around the wall/floor junction and across day work joints to collect ingressing water and divert it to one of two Titan Pro-White sump chambers. Inside each chamber are twin Newton NP400 pumps for pumping water away from the property.

The Result

The waterproofing installed by AP Gooch created a completely dry and habitable Grade 3 environment, as defined by BS 8102:2009. The team also completed the work well within the project’s tight time constraints. The client expressed extreme satisfaction with the end result.