Deflector Plain / Minerals

High Performance Polyester Reinforced Waterproofing Membranes

Deflector is a multi-layered bituminised waterproof system designed for use on various types of flat roofing projects including new build and refurbishments, cold roofs and warm roofs using vapour control layers with insulation. This range of membranes feature a polyester core which is saturated and coated in SBS modified bitumen and the upper surface is finished with a choice of either light sand or slate mineral.

When incorporated in a suitably designed and installed multi-layer system, maintained in accordance with BS 8217:2005 – Reinforced bitumen membranes for roofing, Deflector membranes may be expected to last in excess of 10 years.

Key Features & Benefits:

• High performance

• Polyester reinforced

• SBS modified bitumen

• Integral part of 10 year system


Deflector SBS Green Mineral

Accreditations and Certifications

Product Information
Product CodeRoll LengthRoll WidthFinishPallet Quantity
21768m1mPlain30 rolls
21758m1mGreen Mineral30 rolls
21788m1mCharcoal Mineral30 rolls
21798m1mBrindle Mineral30 rolls


Deflector Plain has a sand surfaced membrane and may be used both as an under layer and a cap sheet. Where used as a cap sheet, suitable protection from ultraviolet light is required in the form of either premium grade solar reflective paint or suitable walkway type tiles which are suitable for use over bituminous system.

Deflector polyester cap sheets can be relied upon to react in unison when combined in multi-layer built up roofing systems. Such combinations are readily applicable to roofs with high insulation values where considerable thermal movement is likely to occur.

Installation Guidelines

This product should be installed in accordance with manufacturer recommendations and all relevant national standards and codes of practice, including BS 8217:2005 – the code of practice for reinforced bitumen membranes for roofing.

Mineral Surface Protection

The upper surface of certain Deflector membranes is protected using mineral granules, which are sourced from natural quarrying. The colours of the minerals therefore can sometimes vary depending on seam depths and extraction positions within the quarry. However, after the effects of the weathering and ageing, any variations will become less visible.

Maintenance and Repair

Routine inspection, cleaning and maintenance of the roof membranes should be based on the recommendation in BS 8217:2005. Should it be damaged either during construction or at later date, then the repairs should be made using the same materials so that the performance of the built-up membranes is retained.


Manufactured in accordance with BS EN 13707:2004+A2:2009 – Flexible sheets for waterproofing. Reinforced bitumen sheets for roof waterproofing.

Handling and Storage

The material should be stored vertically on a firm flat surface, and transported stood on end to avoid damage.

Health and Safety

Health and Safety should be observed at all times in accordance with HSE and industry guidance. Specific Risk Assessments and Method Statements should be produced by contractors where necessary to ensure Working at Heights, Fire Safety and Manual Handling rules are compliant with current law and regulations. Health and safety data sheets are available for all materials on request from Chesterfelt.


UKCA certified & CE Marked to EN 13707:2004+A2:2009.
CE Certificate Number: 0086-CPR-595938.
UKCA Certificate Number: 0086 CPR 753192.

Quality Assurance

Deflector membranes are manufactured in accordance with BS EN ISO 9001:2015 – Quality Management Systems (QMS)

Associated Products

Deflector high performance underlay membranes.

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