Screed

Question 1

Why is a screed used over the concrete slab?

Answer 1

It is practice to lay floor finishes to solid ground floors once the slab has dried out (a screed on top). This finishing layer is called a screed.

Question 2

What is a screed made of?

Answer 2

Sand & Cement

Question 3

As the screed does not strongly bond (stick) to dry concrete, what depth is the minimum used to ensure it does not dry too quickly and crack?

Answer 3

65mm thick

Question 4

What type of heating system is most commonly used in conjunction with the screed?

Answer 4

Underfloor heating (buried within the screed)

Question 5

What is a bonded screed and what is the minimum thickness for this type of screed?

Answer 5

When the screed is laid on a concrete base within 3 hours of placing the concrete. Min thickness 12mm.

Question 6

What is a semi-bonded screed and what is the minimum thickness for this type of screed?

Answer 6

When the screed is laid on a concrete base that has set and hardened. Min thickness 40mm.

Question 7

What is an unbonded screed and what is the minimum thickness for this type of screed?

Answer 7

When the screed is laid on an impermeable DPM (no bond between screed + concrete base). Min thickness 50mm with reinforced light mesh.

Question 8

Describe a floating floor screed. And what is its minimum thickness?

Answer 8

When the screed is laid on top of insulation. At least 65mm thick for domestic & 75mm for other buildings.