Anhydrite Screed

What is an Anhydrite Floor Screed?

McGrath has delivered the advantages of pumpable cement screeds for some time, but modern builders demand, safe, efficient & cost effective materials that respect the natural environment as much as they enhance the buildings in which they are used. Anhydrite floor screeds are a ‘high tech’ flowing screed designed for ease of use in commercial & domestic projects. Anhydrite floor screeds utilise a chemically engineered binder (calcium sulphate anhydrite) made for us by our partner Francis Flower (Northern) Limited. When mixed with selected sands the FF07 binder provides a self-levelling, self-compacting floor screed of strength equivalent to traditional cement but with additional benefits.

Why use an Anhydrite Floor Screed?

It’s Safe:

Anhydrite floor screeds are placed by pump and flows easily without vibration, no tamping or surface finish is necessary, just ‘dapple’ the surface lightly to remove entrapped air. No back breaking bending or knee damaging float work.

It’s Economical:

Anhydrite floor screed can cover up to 20 times more area in a day than traditional sand and cement. Thinner layers mean less material, needs no reinforcement.

It’s efficient:

With minimum preparation a contractor can place 5-6m³ in 30 minutes using readily available small pumps. Anhydrite floors will not curl and have minimal cracking.

Benefits

• Highly beneficial when used in conjunction with underfloor heating
• Self-compacting, high strength, rapid laying
• Less labour intensive compared to conventional screeds
• Thinner application compared to conventional screeds
• Substantial installations of approx. 1,900m² can be laid in a short period
• Control joints only required when a continuous area exceeds 40m in length
• Low laitance
• Under proper conditions light traffic can be carried after 24hours
• No shrinking or cracking
• Delivered to site ready-mixed
• Substantially low carbon footprint

Considerations

Anhydrite floor Screeds are not recommended for outside applications and/or wet areas inside or outside e.g. showers, saunas. If laitance does occur the surface finish may require sanding.

Floor Coverings

As with most screeds Anhydrite Floor Screeds are not a wearing surface and must be covered with a suitable floor covering. Most standard floor coverings can be applied.

As with all good Anhydrite Floor Screeds, mixes are laboratory tested to ensure the effect of the sand is not harmful to the finished screed.