Composite Rate Build Up for Ground Floor Construction – Approximate Quantities in Elemental Estimate Layout

Composite Rate - Ground Floor Construction

Composite Rate Build up – Floor Construction

In this example, the Elemental Estimate layout and grouping of items will be used. There are principles that you have to follow when building up composite rates for Approximate Quantities. We are going to illustrate a composite rate build-up for Ground Floor Construction:

Topsoil excavation average depth 150mm, 100mm surface concrete bed (30MPa) on DPM, on 25mm thick sand blinding under floors, over 150mm hardcore filling on compacted ground including ant proofing and mesh wire reinforcement.

Step 1

First, you have to determine the Group unit of measurement. When you are measuring Ground Floor Construction 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 Floor Construction by area. These are:

Topsoil excavation – (m2) Rate – 5.00
Surface concrete bed – (m3) Rate – 1200
Mesh wire reinforcement – (m2) Rate – 125.00
DPM – (m2) Rate – 7.00
Sand blinding under floors – (m2) Rate – 35.00
Hardcore filling – (m3) Rate – 40
Ground compaction – (m2) Rate – 5.00
Ant proofing – (m2) Rate – 7.00
Striking off and floating top surface – (m2) Rate – R10
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 – GROUND FLOOR CONSTRUCTION	Rate – Cost Per Square Metre (m2) Rands
1m2 of Topsoil excavation
1m2 = R5.00	5
1m2 of Surface Concrete Bed
100 x 1000 x 1000
0.10 x 1 x 1 = 0.10m3
0.10m3 x 1200 = R120	120
1m2 of Wire Reinforcement
1m2 = R125	125
1m2 of DPM
1m2 = R7.00	7
1m2 of Sand Blinding
1m2 = R35	35
1m2 of Hardcore Filling
150 x 1000 x 1000
0.15 x 1 x 1 = 0.15m3
0.15m3 x R40 = R6.00	6
1m2 of Ground Compaction
1m2 = R5.00	5
1m2 of Ant Proofing
1m2 = R7.00	7
1m2 Striking off and floating
1m2 = R10	10	320

1m2 Ceramic floor tiles
1m2 = R250	250
1m2 Screeds
1m2 = R30	30	280
Composite Rate – GROUND FLOOR CONSTRUCTION	600

The composite rate for GROUND FLOOR CONSTRUCTION is R600 per square metre.

Elemental Layout and Grouping

Items which go into the element GROUND FLOOR CONSTRUCTION and component Solid Floors are stated in the description:

	Unit	Quantity	Unit Rate	Cost/m2	Subtotal	Cost
GROUND FLOOR CONSTRUCTION
Solid Floors:
100mm Mass concrete surface bed on USB Green DPM on sand bed, over hardcore filling on prepared ground, including ant proofing and mesh wire reinforcement.	M2		320


Subtotal GROUND FLOOR CONSTRUCTION	M2

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	M2