Choosing a CA grade for Ely apartments and plots
Grades for calcium sulphate screeds come from the European standard for screed materials. The designation starts CA, then gives compressive strength as C and flexural strength as F, both in N/mm2. Light domestic traffic needs no more than CA-C20-F4. Most homes, apartments and offices use CA-C25-F5. Heavier use takes CA-C30-F6.
For Ely apartment blocks and new-build plots, the grade is set by the structural engineer or developer, and we pour what the drawings specify. Now and then the drawings name an alpha hemihydrate product, picked for quicker drying or a thinner section. Each has its own data sheet setting depth, drying and heating, and we keep to it.
Its great strength is how little it shrinks. Bays can be far bigger than with cement, with fewer joints, which suits Ely apartment floors and broad open-plan ground floors. Where joints are needed, across door thresholds or between separate heating zones, we set out the bay and joint layout before the pour so everyone on site knows where they fall.
We can also prepare the full build-up with our own team, including insulation, membrane and edge strip, so the screed is not poured onto a base someone else has left short. See insulation and membranes for that part of the work, and the anhydrite screed guide for more on the material.
Laitance, moisture limits and wet areas in Ely
Two steps separate a poured anhydrite floor from a finished one. The first is laitance: a thin, weak layer that rises to the surface as calcium sulphate dries. Adhesive and primer will not hold to that skin, so when the floor is dry enough we sand it off, clear the dust and use a primer suited to calcium sulphate.
The second is moisture. Calcium sulphate often has a tighter moisture limit from flooring makers than cement, which is why a hygrometer decides, not the look of the floor or the date on the calendar. Underfloor heating, once in, can usually help force dry it after roughly 7 days.
Calcium sulphate is not for rooms that may stay wet. In an Ely apartment, the bathrooms and any wet rooms are better in a cement based flowing screed, which we can pour on the same programme. The same goes for commercial kitchens or wash areas. The drying and laitance notes are handed over in writing for the flooring contractor, so they know what has been done.
For the whole-floor picture on a heated plot, see heated screed for Ely homes.
Anhydrite & Flow Screed prices in Ely
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 Ely
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 Ely
As the crow flies, our yard in Slough is about 71.4 miles from Ely, which lies to the north-north-east. Postcodes here include CB7, and Soham (5.7 miles), Chatteris (9.9 miles), Newmarket (12.4 miles) and March (12.6 miles) are close by.
More on anhydrite screed, part of our screeding services.
