FINISHING

Floor Screed

Cement-sand layer laid over a base slab to give a level surface for the final floor finish

Also calledscreedscreedinglevel screedtopping screed
Related on InfraLens
CODES
Definition

A floor screed is a relatively thin layer of cement-sand mortar (or fine concrete) applied over the structural base slab to bring the floor to the correct level, falls and surface regularity ready to receive the final finish (tile, stone, vinyl, epoxy, carpet) or, in the case of a wearing screed, to act as the finished surface itself. Types include bonded screed (thin, ≥25-40 mm, bonded to a prepared slab), unbonded screed (over a membrane, ≥50 mm) and floating screed (over insulation, ≥65-75 mm).

Typical mix is 1:3 to 1:4 cement:sand; thickness, mix and curing are critical — under-thick or poorly cured screeds crack, debond and become 'hollow' (drummy), the most common screed defect, requiring removal before tiling. Surface regularity is checked with a straightedge; level/falls are set out from datum and screed rails. Bonding, slab preparation (roughening, slurry coat) and curing follow IS 456 + good-practice flooring specifications.

Where used
  • Levelling base for tile/stone/vinyl/epoxy finishes
  • Setting bathroom + terrace falls to drains
  • Floating screeds over thermal/acoustic insulation
  • Wearing screeds for utility/service areas
  • Pre-finish flatness + level correction
Acceptance / threshold
Mix, minimum thickness + bonding per screed type; cured per IS 456; surface regularity within the flooring tolerance and no hollow/drummy areas before the final finish is laid.
Frequently asked
What is the purpose of a floor screed?
To create a level, regular, correctly-graded surface over the structural slab so the final floor finish can be laid true — or, for a wearing screed, to act as the finished surface itself.
Why do screeds crack or sound hollow?
Usually from poor bonding/slab preparation, inadequate thickness, too-rich or too-wet mix, or insufficient curing. Hollow ('drummy') debonded screed must be removed and re-laid before tiling.
Related terms