Specifying anhydrite grades for Gillingham flats and plots
Every calcium sulphate screed is sold to a designation set by the European standard for screed materials. Read it as two strengths in N/mm2: compressive (the C value) and flexural (the F value). In practice, three grades cover the usual range. CA-C20-F4 is for houses with light foot traffic. Homes, apartments and offices in general use CA-C25-F5. CA-C30-F6 goes where loads or footfall are heavier.
Then there are alpha hemihydrate products. They come in where quicker drying or a slimmer floor is needed, say to get under an existing door, and each is laid by its own product sheet, not general guidance.
The appeal of calcium sulphate on a block of flats or a row of new plots is its low shrinkage. Bays can be much larger than with a cement screed, with fewer joints to plan around. Before pouring, we mark out bays and joints around the doorways and wherever heated floor meets unheated.
Since 2015, 8% of Gillingham's current homes have been built. On new build sites the screed usually arrives on a tight programme, with dry lining, kitchens and floor finishes queued behind it. For the heated floors that often go with them, see screed over underfloor heating. The anhydrite screed explainer in our guides covers the material at greater length.
Preparing Gillingham anhydrite floors for their finish
Calcium sulphate needs specific care between the pour and the flooring. Curing brings a weak skin of laitance to the top, and it has to come off, normally by sanding after the floor is dry. Leave it on and adhesives and compounds end up bonded to a skin that can come away. We give you written drying and laitance advice when we finish.
Moisture testing is the next step, and it catches people out. A floor can look dry and still be too damp, because many flooring makers set calcium sulphate a lower limit than cement. Trust a hygrometer reading; on a heated floor, running the system can usually hurry drying along from about 7 days.
Priming comes last. With laitance removed and the moisture test passed, the primer goes on, and it must be formulated for calcium sulphate. Our floor levelling service can follow on with compound if a thin finish needs a smoother surface.
Keep calcium sulphate away from anywhere that may get wet. Wet rooms, plant rooms and garages need a cement flowing screed instead, while a warehouse unit at Gillingham Business Park is usually better served by a high strength screed.
Anhydrite & Flow Screed prices in Gillingham
Liquid flowing screed (which includes anhydrite): £24 to £31 per m² supplied and laid (MyJobQuote, August 2026), so £960 to £1,240 for 40 m². MyJobQuote does not say whether these figures include VAT. See our floor screeding cost guide or screed calculator.
Who lays your anhydrite and flow screed in Gillingham
K & B Screeding’s own team, led by director Donatas Bardisevicius. Founded 2019, company 12298780.
See what customers say in our Google reviews and on our testimonials page.
Anhydrite & Flow Screed from Slough to Gillingham
As the crow flies, our yard in Slough is about 54 miles from Gillingham, which lies to the east. Postcodes here include ME8 and ME7, and Chatham (2.5 miles), Rochester (3.5 miles), Snodland (6.5 miles) and Sittingbourne (7.1 miles) are close by.
More on anhydrite screed, part of our screeding services.
