Reading an anhydrite grade on a Banbury plot drawing
Pick up the floor drawing for a new Banbury house and the screed line will read something like CA-C25-F5. Split it into three parts. CA tells the supplier the binder is calcium sulphate. The figure after C is how hard the cured floor resists crushing, in newtons per square millimetre, and the figure after F is how well it resists bending, measured the same way. Those letters come from the British and European standard for screed materials.
For an OX16 bedroom or lounge with light foot traffic, a designer may settle on CA-C20-F4. The middle grade, CA-C25-F5, is what most Banbury houses and apartments end up with, and offices too. Heavier traffic justifies CA-C30-F6. What goes down the hose is the grade on the paperwork, never a substitute.
Alpha hemihydrate mixes are a separate choice, made when a Banbury programme needs the floor to dry faster or when the build-up leaves little depth to play with. Each brand's own sheet sets its depth, drying and heating times, and that sheet rules the pour.
The material barely moves as it cures, which lets a long kitchen knock-through in Ruscote, or a broad open ground floor on a recent plot, go down in big bays with few joints. Hillside plots in Hardwick and Bretch Hill can have stepped floor levels, so on those we fix every level and every bay edge before the hose is connected, with joints at thresholds and between heating zones.
Pipes under the pour? The Banbury underfloor heating screed page sets out cover depths, and our anhydrite screed guide goes further into how the material behaves.
Before flooring goes onto Banbury anhydrite floors
An anhydrite floor in a Banbury flat or house is not ready the day it looks dry. Three jobs come first.
Sanding. As the screed cures, fine particles rise and leave a soft crust on top, known as laitance. Once the floor has dried, that crust is ground back with a sander and the dust is vacuumed off. Tile adhesive or levelling compound spread onto the crust grips only the crust, and that is how finishes lift. Where your own fitters are not doing it, the floor preparation service covers it.
Testing. A hygrometer reading tells you the relative humidity in the slab, and many vinyl, LVT and wood makers ask for a lower figure on calcium sulphate than they would on a cement base. Judging it by eye is not a test. With pipes in the floor, gentle heating can usually start at about a week to help it along.
Priming. The sanded, dry surface takes a primer made for calcium sulphate before any cement based product touches it.
Wet zones are the exception. With 17% of Banbury homes in purpose-built blocks, plenty of floors in town sit inside apartments, and where one of those has a level access shower or a plant room, that area takes a flowing screed with a cement binder instead. Our written handover notes cover drying and laitance for your fitter.
Anhydrite & Flow Screed prices in Banbury
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 Banbury
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 Banbury
On the map, Banbury sits north-west of Slough, about 47 miles from our base in a straight line (postcodes including OX16), next to Brackley (8.3 miles), Bicester (13.8 miles), Buckingham (15.4 miles) and Daventry (15.4 miles).
More on anhydrite screed, part of our screeding services.
