# How do I know how much screed I need?

## How do I know how much screed I need?

To determine the screed required for a slab, enter the length, width and average depth of the proposed slab. For a trench, you’ll need the total length of the trench’s centreline, as well as the average width and depth.

## How do you calculate sand and cement for a screed floor?

A floor screed is usually a cementitious material made from a 1:3 or 1:4.5 ratio of cement to sharp sand.

How thick does floor screed need to be?

Traditional screeds, when floating, must be a minimum of 75mm thick for commercial projects and may be reduced to 65mm for domestic only situations. A floating Cemfloor screed would need to be minimum 35mm thick for a domestic application and 40mm thick for a commercial application.

### How much is Screeding per square meter?

How much does a screed floor cost?

Floor screed calculator Cost + VAT (Range low – high) Average cost
Screed with mesh reinforcement £28 – £30 per m2 £29 per m2
Liquid screed cost £19 – £24 per m2 £21.50 per m2
Fast drying screed cost £18 – £22 per m2 £20 per m2
Labour costs £12 – £16 per m2 £14 per m2

### How much self leveling screed do I need?

As a guide, a 20 kg bag of PRO GRIP SELF LEVELLING SCREED® will cover approximately 3.5 m² when applied onto a relatively even surface to a thickness of 3mm.

How many bags of screed do I need?

You need 15 bags of cement to 1m3 sharp sand to create 0.9m3 of 4:1 screed.

#### How heavy is a cubic metre of floor screed?

The data sheets by cemfloor say it is 2,000kg per cubic metre. That means a 2.8 square metre insulation board will have 2,80kg of weight on it. Liquid screed doesn’t look this heavy at all from the videos.

#### How many bags of cement make 1m3 screed?

15 bags
You need 15 bags of cement to 1m3 sharp sand to create 0.9m3 of 4:1 screed.

How do you bond screed to concrete?

Fully bonded screeds need to be laid on a shot-blasted / scabbled concrete base, and be bonded using an adhesive such as PVA, SBR, epoxy resin or good old fashioned cement. PVA glue is a good screed adhesive especially if it is mixed with water & cement, to make a slurry.

## What is the thinnest you can lay screed?

Traditional bonded sand cement screeds, generally should not be installed to a thickness less than 15mm. Engineered screeds from the ScreedMax Pro range including the Mapei Topcem screed can be installed to a minimum of10mm.

## Can you screed straight onto Celotex?

Yes laying the screed direct onto insulation is standard practise for a floating floor. A standard sand/cement screed would need to be laid at a minimum depth of 65mm for a domestic property. If modified screed is used you can get down to 55mm.