Composite Rate Build Up – Upper Floor Concrete Slabs
The Elemental Estimate layout and grouping of items will be used in this example. When building up composite rates for Approximate Quantities, you have to follow some basic principles. We are going to illustrate a composite rate buildup for Upper Floor Concrete Slabs:
200m Thick solid reinforced concrete slabs for upper floor 25MPa, steel reinforcement 120kg/m3, rough formwork to soffits, striking off and floating the top surface, including plaster and paint to soffits. Ceramic floor tiles fixed with adhesive on 25mm screed.
Step 1
First, you have to determine the Group unit of measurement. When you are measuring Upper Floor Concrete Slabs in Elemental or Approximate Quantities estimating, the group unit of measurement is the square metre (m2).
Step 2
The second step is listing all associated Bill items that can be mapped to Upper Floor Slabs by area. These are:
 Reinforced concrete slab – (m3) Rate – R1500
 Steel reinforcement to slabs – (Tonne) Rate – R10,000.00
 Formwork to soffits – (m2) Rate – R175
 Striking off and floating top surface – (m2) Rate – R10
 Plaster to concrete soffits – (m2) Rate – R30
 Paint on plastered soffits – (m2) Rate – R30
 Ceramic floor tiles – (m2) Rate – R250
 Screeds – (m2) Rate – R30
Step 3
Since your Group unit is the square metre (m2), you should convert the Bill item rates to Cost per Square Metre.
Rate Build Up
GROUP – SLABS 
Rate – Cost Per Square Metre (m2) Rands  
1m2 of Concrete slabs:  
200 x 1000 x 1000  
0.2 x 1 x 1 = 0.2m3  
0.2m3 x R1500 = R300  300  
1m2 of Steel reinforcement:  
Slabs reinforcement density value = 120kg/m3  
200 x 1000 x 1000  
0.2 x 1 x 1 = 0.2m3  
0.2m3 x 120 =24kg = 0.024 tonnes  
0.024 ton x R10,000 = R240  240  
1m2 of Formwork to soffits:  
1m2 = R175  175  
1m2 Striking off and floating:  
1m2 = R10  10  725 
1m2 Plaster to soffits:  
1m2 = R30  30  
1m2 Paint to soffits:  
1m2 = R30  30  60 
1m2 Ceramic floor tiles:  
1m2 = R250  250  
1m2 Screeds:  
1m2 = R30  30  280 
Composite Rate – SLABS  1065 
The composite rate for UPPER FLOOR SLABS is R1065 per square metre.
Elemental Layout and Grouping
Items which go into the element STRUCTURAL FRAME and component Slabs are stated in the description:

Unit  Quantity  Unit Rate  Cost/m2  Subtotal  Cost  
STRUCTURAL FRAME


Slabs:


200mm Solid reinforced concrete slab, steel reinforcement 120kg/m3, formwork to soffits, striking off and floating top surface.

M2  725  
Subtotal STRUCTURAL FRAME 
Items which go into the element FLOOR FINISHES and component Applied Floor Finishes are stated in the description:

Unit  Quantity  Unit Rate  Cost/m2  Subtotal  Cost  
FLOOR FINISHES


Applied Floor Finishes:


Allow a PC Sum of R150/m2 for Ceramic floor tiles fixed with adhesive on/and including 25mm screed.  M2  280  
Subtotal FLOOR FINISHES 
Items which go into the element CEILINGS AND SOFFITS and component Slab Soffit Finishes are stated in the description:

Unit  Quantity  Unit Rate  Cost/m2  Subtotal  Cost  
CEILINGS AND SOFFITS


Slab Soffit Finishes:


One coat cement plaster on concrete soffits and two coats Polvin Super Acrylic PVA paint plus undercoat, including preparing surfaces.  M2  60  
Subtotal CEILINGS AND SOFFITS 