QUALITY PERFORMANCE COMPARISON TABLE
HEMIHYDRATE SCREED SAND: CEMENT SCREED
PRODUCTIVITY – 2000m2 per day – 200m2 per day
HOW QUICKLY CAN I WALK ON THE FLOOR – After 24hrs
– No curing required

– Shouldn’t be walked on for 7 days
– Should be covered and cured
MOVEMENT JOINTS – Up to 2000m2 within 1:6 aspect ratio – Max 40m2 or every 6 linear metres
PERFORMANCE – Very low shrinkage
– Minimal Cracking
– Will not curl
– Shrinks
– Cracks
– Curls
SURFACE FINISH – SR2 under BS8204 easily achieved – Depends on contractor
– Curls and cracks at joints
LAYING DEPTHS – Floating on insulation – 40mm min – Floating on insulation – 75mm min
AVERAGE DRYING TIMES – 1mm per day up to 40mm
– Can be force dried after 7 days
– 7 months @ 100mm thickness
– Cannot be forced dried
TYPICAL UNDER FLOOR HEATING RESPONSE TIME – Within 2 hours, laid at 50mm depth – Typically next day, laid at 100mm depth
QUALITY CONTROL – Factory produced compliant to BS EN 13454 – Often site mixed with no quality control