Grades, products and bays for Sawbridgeworth new builds
The European standard for screed materials rates calcium sulphate screeds by strength. Take CA-C25-F5 on a Leventhorpe Chase style drawing: 25 is the crushing strength and 5 the bending strength, both measured in N/mm2.
Residential jobs mostly use one of three. CA-C20-F4 goes into domestic floors with light traffic, CA-C25-F5 into most homes, apartments and offices, and CA-C30-F6 into areas with heavier use. On a new-build plot, the engineer picks and we pour that grade exactly.
Occasionally an engineer wants alpha hemihydrate instead, to dry sooner or to save depth. Its own product data sheet sets minimum depth and drying, and we follow that sheet over any general rule.
Anhydrite hardly moves as it cures, and that is its real selling point. Wide bays go down with few joints, suiting apartment floors and open-plan ground floors. Our own team plans the bays and joints before the pour and prepares the full build-up, including insulation and edge strip.
Plots with heating loops can usually have them switched on gently from around day 7 to speed the drying. Where heating is fitted, the specification also fixes the cover over the pipes, at least 25mm for a liquid screed. For a fuller introduction, our guide anhydrite screed explained goes into the material.
Sanding, testing and priming before Sawbridgeworth flooring goes down
Drying anhydrite leaves a chalky film over its face, which flooring people call laitance. It has to be sanded away before any adhesive, primer or levelling compound goes on, or the finish will bond to that skin and not the screed. After sanding, a primer made for calcium sulphate is applied.
Moisture testing comes next. Flooring makers are often stricter with anhydrite than with cement, so a pale, dry looking Sawbridgeworth floor may still not pass. A hygrometer reading is taken before flooring, and we record it so the flooring fitter can see it. If it comes back high and heating is fitted, gentle force drying can bring it down.
Water is anhydrite's weakness. So on a new plot, the en-suite with a walk-in shower, any wet room and a utility where pipework might leak are better poured in a cement based flowing mix, or given a hand-laid cement screed for wet rooms. If the base under a pour needs work first, see our floor preparation service. The same material is covered nearby on anhydrite flow screed in Hertford.
Anhydrite & Flow Screed prices in Sawbridgeworth
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 Sawbridgeworth
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 Sawbridgeworth
On the map, Sawbridgeworth sits east-north-east of Slough, about 39.3 miles from our base in a straight line (postcodes including CM21), next to Harlow (3.8 miles), Bishop's Stortford (4.1 miles), Hoddesdon (7.9 miles) and Ware (8 miles).
More on anhydrite screed, part of our screeding services.
