Preparation
All substrates must be clean, sound, with a minimum compressive strength of 25 N/mm² and a minimum pull-off strength of 1.5 N/mm², dry and free of surface laitance. Recommended methods are:
- Powerfloated concrete – use a Vacuum Assisted Shotblaster to remove weak laitance and provide a surface key for the coating. If this is not possible, chemically etch with Polycote Etch IT, then rinse thoroughly and allow to dry.
- Loose paint or rust – remove, using a Vacuum Assisted Shotblaster, Floor Grinder or equivalent method.
- Loose or friable concrete – use a Vacuum Assisted Shotblaster. If this is not possible, chemically clean with Polycote Etch IT then rinse thoroughly and allow to dry.
- Metal – use a shot-blaster to prepare the surface to SA2.5 (bright steel) and primed with ZP Primer. Deckplates of 4mm or less do not provide a sufficient substrate for Flortex PU Screed, please contact Polycote Technical Helpline for further information.
To give a professional finish, we advise that grooves are cut into the floor around the perimeter of the substrate, to give the screed an anchorage. The groove should be about 20mm wide and 8mm deep and about 150mm from the edge.
Mixing
Once the surface has been thoroughly prepared, a suitable primer has been applied, and the surface is tack free, apply Flortex PU Screed.
Prior to mixing, the temperature of the three components must be between 15°C and 25°C. Stir the individual components before mixing together.
Add Part ‘B’ to Part ‘A’ and thoroughly mix for at least 1 minute. Steadily add the aggregate whilst continuing to mix. Mix thoroughly for 3 minutes once all the aggregate has been added.
For best results use a heavy duty slow speed drill (300 – 400 rpm) with a mixing paddle. Mix until a lump free consistency is obtained.
Ensure thorough mixing as an unmixed product will result in a poor or non-cure situation.
Application
Once fully mixed, apply the product between the battens (if necessary) and level with a steel float. If a smooth finish is required (to assist cleaning), back-roll with a short pile roller. Ensure all chases and toe-in grooves are fully filled. Blend each mix into the previous application, avoiding disturbance of material that has commenced setting.
Application Temperature
Normal application temperature is between 15°C and 25°C. Air humidity must not exceed 90%. Flortex PU Screed should be room temperature when applied, if the product is warmer than usual, pot life and curing times will be reduced. Similarly, times will be extended in colder applications.
Newly installed floors must be protected from damp, condensation and water for a minimum of 24 hours at 20°C. Maintain ambient temperatures above 10°C for at least 24 hours following installation. The substrate and uncured floor must be kept at least 3°C above the dew point to prevent condensation or surface blooming.
