Author: Danny Neill - Operations Manager at Platinum Chemicals Ltd How To Seal Concrete Floor Joints Floor joints are often subject to movement due to varying causes. Examples include expansion and shrinkage because of transport loads (forklifts, lorries), but also weather and fluctuations in temperature. Common Applications Include: Industrial Floors (Production Halls, Warehouses) Public Spaces (Railway Stations, Pedestrian Zones, Shopping Centres) Car Parks Specific Projects (Petrol Stations, Barns) Important requirements for floor joint sealants are excellent bonding (to concrete or aluminium for example) and high elasticity. For specific projects, chemical resistance (to fuels or cleaning products) or drivability (transport) can be relevant as well. Platinum Chemicals offer some quality products for floor joint projects. Recommended Floor Joint Sealants SOUDAFLEX 40FC - High Quality, High Modulus Polyurethane Sealant / Adhesive with excellent mechanical performance and chemical resistance for a wide range of bonding and sealing applications on concrete (i.e. floors and walls) and metals. SOUDAFLEX 36FL - Superior Quality, Chemical Resistant Polyurethane Floor Sealant for use in flooring expansion joints where high movement is expected, and for flooring joints where exposure to fuel and oil is expected, such as garages, forecourts etc. SOUDAFLEX 33SL - Self-Levelling Polyurethane Flooring Sealant which stays elastic after curing. Very good adhesion on many materials. Excellent resistance to many chemicals. Developed especially for concrete flooring applications. Products Required One of the Above Sealants Soudal Primer 100 Soudal Manual Foil Cartridge Gun PU Backing Rod (Optional) Soudaglatt - Flexible Smoothing Tool Clean Hand Brush Safety Knife Masking Tape Hand Pressure Sprayer with Clean Water Step By Step Instructions 1) Clean the Floor Joint Remove all dirt and loose pieces of cement or concrete. Use a clean hand brush to remove the dust. 2) Tape off the Joint Edges Use Masking Tape to neatly tape off the sealant edges. This will prevent excess sealant smearing beyond the joint. 3) Apply Backing Rod if Required Insert a suitably sized PU Backing Rod to the required depth before application of a Primer. Generally speaking, if the depth exceeds 25mm, a Backing Rod should be used, this avoids sagging or slumping of the sealant. 4) Apply Primer if Required To achieve maximum performance and results on POROUS substrates, apply Soudal Primer 100 to the joints by brush in one full covering layer. Soudal Primer 100 should always be applied on Natural Stone (i.e Granite, Marble etc.). Soudal Primer 100 is not required on non-porous substrates. The sealant should be applied between 1 hour (minimum) and 4 hours (maximum) after application of Soudal Primer 100. 5) Open the Cartridge Place the unopened Foil Cartridge in the barrel of the Manual Foil Cartridge Gun. Using a sharp safety cutter, pierce and cut off the top of the foil cartridge before screwing back on the applicator nozzle. You are now ready to start sealing. 6) Start Sealing Place the nozzle where you want to start sealing. Squeeze the handle and move the Cartridge Gun over the joint in a smooth movement. Apply sufficient sealant to ensure that the joint is adequately filled product adheres well. 7) Smooth and Remove the Tape Using the Pressure Sprayer lightly spray the joints with Clean Water. Smooth the joint by using the Soudaglatt Smoothing Tool, or a wet finger, and immediately remove the Masking Tape before the sealant starts to skin. Smooth carefully again to smooth away any protruding edges. Note: Tooling is not required if using Soudaflex 33SL as this a self-levelling sealant. Feature Image: Soudal