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The Newton Waterproofing Index is a unique specification tool in the construction industry, providing specifiers and designers with a scoring system through which it is possible to accurately assess the level of risk and potential success involved in a waterproofing design.

To assist the specifier in deciding on the correct waterproofing specification, the Newton Waterproofing Index (or ‘NWI’) is a unique waterproofing specification tool which has been developed as a means of assessing the ability of a waterproofing specification to successfully protect an earth-retaining or below-ground structure. This assessment is based both upon the type of structure involved, and the type/s of waterproofing being used.

The purpose of the Newton Waterproofing Index is to give specifiers an accurate understanding of the potential success of different specifications and builds, as well as helping to guide them through the myriad of different waterproofing products and combinations available in the market. Visually, this assessment is then represented as a NWI ‘score’ that can be used to judge each waterproofing specification.

Newton Index

The Scoring System

The scoring system works in conjunction with the British Standard for waterproofing, which defines the three types of desired internal environment as Grades 1, 2 and 3. By reflecting these Grades in the scores, the Index makes it quick and easy to visually assess a design, from 0 through to 4.0.

Once assessed by Newton, designs are appointed with a scoring range, due to the fact that even within an agreed specification, the effectiveness of the waterproofing depends on the competency of the installation. For ease, these scoring ranges will also be presented on a scale.

The lower score indicates the standard that can be achieved even with imperfect workmanship, indicating a safer specification that will result in a good level of waterproofing, even if the installation and build are not of the highest standard.

The upper score can be achieved by those that are trained in the installation. The larger the range, the higher the risk that an imperfect installation will affect the waterproofing.

The Scoring Scale

Newton scoring scale

Comprehensive Solution Sheets

Newton Solution Sheets are an integral specification tool within the Index, each bringing together key product information, NBS Clauses and 3D drawings into one complete resource. Each Solution Sheet also carries an Index score that is defined by the specification and the structure to which it is applied.

Info Sheets

Speak to our friendly, expert team

Our staff are able to provide guidance for projects of all sizes, whether you require some general advice about damp or waterproofing, or support with technical drawings and specifications.

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