Xtra-Load Diamond Self-Adhesive Tanking Membrane

Xtra-Load Diamond Self Adhesive Tanking is specifically designed for use as a below ground waterproofing tanking membrane in critical areas such as internal and external tanking of underground structures, reservoirs, subways, liftshafts and retaining walls. Its self-adhesive properties enable the membrane to be applied internally or externally to a variety of substrates.  

Features & Benefits

  • Ease of application.
  • Resistant to tearing.
  • Compatible with all forms of DPM’s and DPC’s.
  • Joints and seals easily.
  • High water vapour resistance.
  • British Board of Agrement Approved

Product Range

Xtra-Load Diamond is manufactured from tough, cross-laminated 0.1mm thick HDPE film, laminated to a 1.4mm thick layer of modified rubber bitumen adhesive. When fully protected and subjected to normal service conditions, Xtra-Load Diamond will provide an effective barrier to the transmission of water and water vapour for the lifetime of the structure in which it is incorporated.

Product Code Description Roll Size Roll Weight
3100423 Xtra-Load Diamond Self Adhesive Tanking 19.05m x 1.05m 34kg


Product Data and Performance

Performance Data
Nominal Thickness: 1.5mm
Nominal Weight: 4.0 kg/m-2
Water Vapour Permeability: 0.23gm-2 day-1
Water Vapour Resistance: 892 MNsg-1
Tensile strength:

218.5(1) \ 262.5(2) N/50mm

Elongation at break:

210%(1) , 160% (2)

Dimensional Stability:

-0.1%(1) , -0.2% (2)

Adhesion: 3.5N/mm

(1) Machine Direction  , (2) Transverse Direction


Compatibility: Xtra-Load® Diamond is compatible with concrete, smooth brick and blockwork or screeded substrates, and is resistant to those chemicals with which it is likely to come into contact. However, care should be taken to prevent contact with mould oil and hydrocarbons.

Resistance To Puncture: Provided sharp objects are not present prior to and during installation of the protective layer, the tanking membrane will not be damaged by normal foot traffic.

Resistance To Moisture: When completely sealed and consolidated Xtra-Load® Diamond will meet Building Regulations requirements in the resistance of the passage of moisture from the ground. The membrane is impervious to water.

Installation Details

Xtra-Load® Diamond must be installed in accordance with the requirements of 'BS 8102: Code of practice for protection of below ground structures against water from the ground' and 'BS 8000-0: 2014. Workmanship on construction sites. Introduction and general principles', and in accordance with the BBA certificate. Tanking should be externally applied wherever possible and immediately protected.

Preparation Of Surface: All surfaces should have a smooth finish, free from cavities, projections and mortar deposits. Surfaces should be dry and free from dust and frost. Concrete surfaces should be dense.
Vertical surfaces of brick and blockwork should be dry and rendered to provide an even surface. Brick or blockwork not rendered must be flush pointed to give a smooth surface without sudden changes in level.

Priming: Prior to application of the membrane, a priming coat of Icopal SA Bitumen Primer must be applied to all surfaces and allowed to dry.

Angles And Corners: Where the horizontal surface meets the vertical surface, a 50 mm by 50 mm fillet should be used, reinforced with a strip of membrane. Reinforcing angles are formed by cutting a 300 mm strip of Xtra-Load® Diamond from the roll. 

Membrane Application: The ideal application temperature range is 5°C to 35°C. At low temperatures the products will become progressively stiffer, which may make it difficult to handle. The membrane rolls should be left in a heated storage area until immediately before application.

The tanking membrane should be applied only when atmospheric and substrate temperatures are greater than 5 °C. The surface of the substrate should be clean and dry and must be 3 °C above the dew point. If the surface is below or at dew point temperature then moisture can form at the surface and affect membrane adhesion.

Apply Icopal SA Bitumen Primer by brush or roller and leave until dry (approx 45 minutes to 1 hour, depending on weather conditions). The release paper should be removed in a continuous strip for the first 500 mm of the roll and the membrane pressed firmly into position to ensure no air pockets are formed.

Xtra-Load® Diamond self-adhesive tanking membrane is supplied with a selvedge. Align adjacent rolls of Xtra-Load® Diamond tacky side down, allowing a side overlap of 100 mm and end overlaps of 150 mm. Peel back the release paper and the selvedge as laying progresses. Press down roll joints firmly to develop and immediately bond, and to ensure a water-tight seal. The use of a hand roller will aid in providing a firm seal.

Vertical work: The tanking membrane should be applied starting at the top of the section of vertical wall. Using the action of gravity to aid installation, the backing sheet should be removed and the membrane well rollered down working from the middle to the edges to remove any pockets of air and to ensure a full bond to the substrate.

Membrane Protection: On completion, the tanking membrane must be immediately protected following a detailed inspection for damage and faults. To ensure Xtra-Load® Diamond is not damaged during backfilling or by following trades, a screed, or non-rot protection board, such as the Xtra-Load® Protection Board, should be laid immediately following application.

    Contact Icopal 0161 8654444

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