Radflex S200 A1: Download Data Sheet

Flush Surface Expansion Joint

This versatile mechanical expansion joint has been developed to accommodate exposure to a wide range of traffic conditions in a variety of applications such as multi-storey car parks, shopping centres, loading bays and bridges. The effective, durable system is equally applicable to new work and refurbishment contracts, where it can be easily accommodated in existing finishes.

The S200 system features the double laminated Radflex 125 waterproof membrane bonded to the substrate, which links the waterproofing on each side of the joint gap. The membrane is then protected by a rubber extrusion and metal reinforced rubber nosings which are anchored through the Radflex 125 into the concrete deck with chemical fixings.

S200i-tech-dwg3DCompound Formulation

The butyl rubber compound formulation of Radflex 125 is tough, weatherproof and flexible, with proven performance worldwide. It is used in conjunction with Radflex epoxy adhesives designed for long-lasting bonding between the rubber and the substrate. The result is a continuous watertight finish throughout the structure.

The extrusion features a specially formulated EPDM rubber compound which has exceptional weathering properties and good flexibility over a wide temperature range. Custom-designed extrusions are available to accommodate specific movement requirements.

Steel Reinforced

Steel reinforced EPDM nosings are utilised to protect not only the membrane but also the edges of surrounding finishes from constant vehicular loads.

The inherently flexible S200 system is suitable for gaps of up to 50mm at mid temperature. It can accommodate rotational and vertical movement criteria of 6mm with  lateral flexibility up to 50mm in a completely watertight joint.


• Closed cell foam
• Polymer modified mortar haunches
• Radflex epoxy adhesive
• Radflex 125 membrane
• Chemical anchors
• EPDM  extrusion
• S200 EPDM nosings (1.83 m lengths)
• Sealants
• Bolt hole caps

Materials Performance

The component parts of the system are non-degradable, unaffected by UV light or ozone and completely impervious to water or water vapour. Once installed, the waterproof membrane is completely protected by the extrusion, ensuring a long-lasting, effective flush surface expansion joint. Robust materials, straightforward installation and proven high performance together meet the exacting standards of the modern construction industry.

Health and Safety

Installation and use causes no ‘health and safety at work’ hazards, provided that manufacturers’ instructions are followed regarding adhesives, sealants and chemical fixings.


Concrete surfaces must be float finished, abraded to remove laitence and provide good bonding substrate. If the concrete surface is unsound, it should be made good with polymer modified mortar, in accordance with manufacturers’ instructions. The concrete shoulders must be smooth and level across the expansion gap. We do not recommend application to lightweight or sand and cement screed.

Mastic asphalt surfaces to which the Radflex membrane is to be bonded must be well sand-rubbed to remove nibs and excess bitumen fat to give a clean, flat surface free from surplus sand. The surface should be ironed smooth and level across the joint.

Reference Installations

Radflex systems are installed in many different traffic conditions in a variety of climates. We are pleased to refer enquirers to relevant applications to confirm satisfaction with the installation and system performance.

Radflex Design Services

Technical advice and design services are available from our Technical Department, including reviewing requirements of particular applications, ensuring installation of the most appropriate Radflex system to suit specific sites and applications. Radflex S200 can be adapted to most types of construction.

Columns, Walls, Kerbs and Corners

Continuity of the waterproof seal is ensured by bonding the Radflex membrane to the surface of the horizontal asphalt/concrete and to the face of skirting asphalt/concrete. The S200 module is finished flush with the up stand. Radflex S200 System kerb units are purpose-made for each application. Internal and external corners can be easily accommodated.

s200diagramsTechnical Specification

Radflex S200 movement joint including Radflex 125 DLM x __mm wide, nosings, extrusion, polymer modified mortar haunches __mm x __mm deep, adhesives, fixings and sealants.  Supplied and installed by Radflex Contract Services Ltd. (Tel: 01322 276363 / 0191 417 6677).


Radflex is a registered trade mark. The Radflex 125 system is the subject of UK Patent 1288314. All reasonable care has been exercised in preparing this data sheet, which to the best of our knowledge is true and accurate.  Due to our programme of continuous improvement, the specification may be subject to updating.