Roof screed job

The following all applies to a flat root cement slab that has slight ponding

You will need to apply the cement in 2 phases, 1- the slurry 2- the concrete mix

When i say by volume, what is meant is that 1 cup of cement gets x cups of aggregate, not weight involved

1- The bonding slurry

  • As thin as you can provided it is “Continuous” and “Worked into the surface”
  • thicker is bad not good
  • Consistency = Thick enough to hold its shape
  • The concrete layer needs to be added IMMEDIATELY after applying the slurry, within lets say 10 minutes in warm weather

2- The concrete mix

The bare minimum height, for something that is not a foot path, and is not expected to hold any weight is 2.5CM ! cement cant be less than that, it will break and create problems later on !

3- The proportions

1- Cement + SBR slurry

Equal amounts of all 3 by volume

1 SBR
1 Watter
1 Cement

The cement mix by volume…

1 cement
3 sand
1 stone dust
2–3 teaspoons per cup of cement, (5–8% of cement volume)