Anhydrite grades for Loughton apartments and new homes
Each grade name is a strength code. So CA-C20-F4 tells you it is calcium sulphate that withstands 20 N/mm2 of compression and 4 N/mm2 of bending, as classified by the European screed standard.
Three grades cover most work. That lowest grade does for lightly used rooms at home. The middle one, CA-C25-F5, suits the general run of houses, flats and offices. Floors that work harder are poured at CA-C30-F6. Alpha hemihydrate products are a separate group, used where a thinner section or faster drying is needed, and they follow their own product data sheet. If a Loughton drawing names one of those products, its sheet sets the depth and the drying advice we work to on site.
Only 10% of Loughton's homes were built since 2000, so new build plots are relatively few. When they do come up, and on apartment floors, a calcium sulphate grade is often in the drawings. It earns its place there: with minimal shrinkage, big bays go down with only a few joints, and it lies well over insulation and heating pipes. We still draw up where bays and joints fall before pouring, paying most attention to doorways and narrow sections.
The material also has its limits, and it is worth knowing them before the specification is fixed. The anhydrite screed guide explains how calcium sulphate differs from cement, and why that matters for drying and for any area that might get wet.
Laitance and moisture checks on Loughton pours
Every calcium sulphate floor needs two jobs done before flooring goes down. First, the laitance has to go: the screed throws up this thin, weak crust as it settles. After drying, we sand it away, clear the dust and prime with a product formulated for calcium sulphate. The sanding falls under our pre-flooring preparation.
The second is moisture testing. Flooring makers often hold calcium sulphate to a stricter moisture figure than cement, so a Loughton flat floor that feels dry can still fail. Only a hygrometer can clear it for covering. Where there is underfloor heating, switching it on gently from about a week in normally speeds the drying.
Wet areas are where this material stops being suitable. Plant rooms, open showers and wet rooms take a flowing mix made with cement in its place. If the finished calcium sulphate surface needs extra smoothness for a thin finish, levelling compound over the sanded screed can follow, with the right primer.
Specifying the same thing in neighbouring Redbridge? See Redbridge anhydrite screed.
Anhydrite & Flow Screed prices in Loughton
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 Loughton
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 Loughton
As the crow flies, our yard in Slough is about 31.8 miles from Loughton, which lies to the east-north-east. Postcodes here include IG10, and Chigwell (2.5 miles), Waltham Abbey (3 miles), Epping (3.5 miles) and Waltham Cross (4.8 miles) are close by.
More on anhydrite screed, part of our screeding services.