Floor screeding

Understand applications and methods of laying sand and cement floor screeds

Aims: Objectives: Floor screeding To introduce floor screeding To understand how to set out and lay floors to receive carpets, ceramic tiles and vinyl

What do you know? Floor screeding What is a bonded floor? Introduction What do you know? What is a bonded floor? What is a semi-dry mix? How are screeds set out for a level floor? How are screeds set out for a floor with falls? What is curing?

Floor screeds Floor screeding Plasterers have always laid floor screeds but large areas now tend to be carried out by companies that specialise in floor screeding. Floor screeds are laid either level or to falls and can incorporate underfloor heating

Floor screeding Mixing proportions Mixing Ready-mixed screed Mixing Mixes are usually 3 : 1 = 3 of coarse sharp sand to 1 of cement 4 : 1 = 4 of coarse sharp sand to 1 of cement Mixing Mixed to a semi-dry consistency (test: it should form a ball in your hand - too dry it will crumble, too much water and you hands will be wet) Ready-mixed screed Delivered to site, can have retarders added if doing large areas; quite often pumped into the building

Bonded floor screed Unbonded floor screed Monolithic Floor screeding Types of floor screeds Bonded floor screed The base is prepared and the screed laid on a pre-laid base Unbonded floor screed The floor screed is laid on a damp proof membrane (DPM) Monolithic The screed is laid no more than three hours after the concrete is laid Floating floor screed This is laid on rigid or semi-rigid insulation boards

Floor screeding Floor screed setting out to level using dots or screed rule

Setting out falls by using square of datum line or packings of dots Floor screeding Falls used for shower or wet room Setting out falls by using square of datum line or packings of dots

Floor screeding Laying floor screed using battens

Floor screeding Floor laid using dot and screed method

Curing and drying out Floor screeding This means stopping the moisture in the screed to allow the cement to reach full strength. You can spray the floor lightly for around 7 days, cover the floor with plastic sheeting to retain the moisture in the screed, or you can spray a chemical on the floor which breaks down when curing is complete.

You should now have the knowledge to complete the following: Floor screeding Conclusion You should now have the knowledge to complete the following: What is a bonded floor? What is a semi-dry mix? How are screeds set out for a level floor? How are screeds set out for a floor with falls? What is curing?

THANK YOU