Newton FlexProof 106 X1 15kg Flexible Construction Joint Waterproofing

In a well-built concrete basement or retaining wall, the concrete itself keeps water out. The weak points are the joints, where one pour meets the next or where sections are designed to move. Those joints are where water is most likely to find a way through, and because buildings shift with temperature, settlement and loading, any sealant used there has to stay flexible without cracking or losing its grip. Newton FlexProof 106 X1 is made for exactly that job.

FlexProof 106 X1 is a thick, thixotropic paste that stays where it's put on vertical surfaces and in vertical joints without slumping. Once applied, it cures into a tough, rubber-like elastomeric membrane with a superb bond to concrete and most other building materials, including block, screed, metal, plastic, timber and glass. It's extremely flexible, so it can absorb significant building movement and remain watertight. It resists water pressure from both the outside (positive side) and the inside (negative side) of the structure, and it isn't affected by the high alkalinity of fresh concrete.

Because it's single-component, there's no mixing, stirring or rushing to beat a pot life. Simply cut open the foil bag, pour, and spread it with a trowel. A rain-tight skin forms within minutes, so a passing shower won't spoil the work, and it performs across a huge temperature range from -40°C to +90°C. It's ideal for waterproofing construction joints in basements and retaining walls, sealing movement joints, bridging joints between different materials, and detailing as part of external waterproofing systems.

Benefits

• Single component, with no mixing or stirring and no pot life to work against
• Highly flexible, staying watertight with up to 20% expansion and compression and 10% shear
• Resists both positive and negative side water pressure
• Thick, thixotropic paste ideal for vertical surfaces and joints
• Rain-tight skin forms within minutes of application
• Excellent resistance to the high alkalinity of concrete
• Strong bond to concrete, block, screed, metal, plastic, timber and glass
• Performs from -40°C to +90°C
• VOC-free

Good to Know

• Supplied as a 15kg foil bag inside a tub, grey
• Construction joints: apply in a 300mm wide band centred over the joint, 2.5mm thick (3.85kg/m²); one tub covers approximately 13 linear metres of joint
• Flat surfaces: apply 2.0mm thick at 3.0kg/m²
• Movement joints: insert a foam backing rod, then fill to a depth of half the joint width
• Mask the edges with tape for a neat finish and remove the tape once cured
• Apply with a trowel or putty knife, using a brush for detailing
• Surfaces must be clean, dry and free from dust, laitance, release agents, oils and paint
• Use a suitable primer on open or porous surfaces, in movement joints, and where resisting water pressure from the inside
• Apply between +1°C and +35°C; do not apply to wet, frozen or icy surfaces
• Ready for protection boards in 20–30 minutes; fully cured in 3–5 days, at roughly 24 hours per mm of depth at 20°C
• Must be protected before backfilling when used on retaining walls
• Do not apply more than 2.5mm thick over joints
• Not suitable as a vehicle or pedestrian traffic surface
• Clean tools with a rag before curing; xylene helps remove partly cured product