Repairing Cracks in Concrete
Impripox is an epoxy that can be poured into cracks in concrete to repair them. Follow the directions below to repair cracks in concrete in advance of applying Microcement.
The mix ratio of Impripox to Impripox Comp B is 5:2 or 1l:400ml. The expected drying time is 12 hours, this may vary depending on external conditions & depth.
Repair cracks under 3mm wide
Use a 5” grinder to open up the crack (take care not to cut into any underfloor heating), hoover out any dust then mix Impripox with Impripox Hardener (Ratio 5:2) and pour into the crack. Leave to cure fully, this will take for at least 12 hours. It may need topping up depending on how deep the crack is.
Mix the ImpriPox with ImpriPox Hardener in a mixing bucket and stir gently with a paint stirrer or Microcement Mixer on a low speed for a few minutes.
The Mix Ratio is 5 x ImpriPox : 2 x ImpriPox Hardener
Repair cracks over 3mm wide
Use a 5” grinder to open up the crack and grind approx 100mm “stitches” horizontally across the length of the crack around 40mm apart (take care not to cut into any underfloor heating), hoover out any dust then insert steel helical stitching bars into the stitches. Mix Epoxy with Epoxy Hardener (Ratio 5:2) and pour into the crack. Leave to cure fully this will take for at least 12 hours. It may need topping up depending on how deep the crack is.
Applying Quartz Sand
Whilst the Impripox is still wet, spread the quartz sand across the surface. Leave to dry. Minimum of 12 hours. Ideally overnight.
Top Tip
It’s imposible to know how deep a crack actually is. If you find it’s taking a lot of Impripox to fill, you could always mix some quartz sand into the Impripox to thicken it up.
Advisable
Whilst this process will fill and add strength to the crack. We would also recommend using the high performance primer option to add further protection against the crack transfering through to the microcement should further movement occur.