Material Use

Specifying efficient use of materials and considering their impact from manufacture to disposal.

Embodied energy case study

The embodied energy of the major components for a 1 storey house of 195 m2 is set out in the following table.

MATERIAL TYPE

APPROX WEIGHT (KG)

EMBODIED ENERGY
INTENSITY (MJ/KG)

TOTAL EMBODIED ENERGY (MJ)

Floors - concrete

17.5 Mpa concrete in floor slab for brick veneer cladding

57,120

1.0

57,120

17.5 Mpa concrete in floor slab with lightweight cladding

53,184

1.0

53,184

Concrete masonry foundation

1,312

0.94

1,233

Reinforcing steel for slab on ground and foundation

789

8.9

7,022

Floor suspended timber (excluding garage slab)

Concrete masonry foundation wall

460

0.94

432

Foundation wall reinforcing

147.5

8.9

1,313

Concrete to footings

13,440

1.0

13,440

Timber framing* air dried, gauged, 600 kg/m3

2,562

1.16

2,972

Particleboard flooring

1,244

8.0

9,952

Windows and glazing

Aluminium window joinery factory coated

144

34.3

4,939

Aluminium window joinery anodised

144

42.9

6,178

Float glass

450

15.9

7,155

Timber framing* 500 kg/m3 @ 12% mc

Timber wall framing ground and first floor kiln dried, gauged

2,255

2.5

5,638

Timber roof framing kiln dried, gauged, light roof

1,875

2.5

4,688

Timber roof framing kiln dried, gauged, heavy roof

1,925

2.5

4,813

Timber ceiling framing and battens kiln dried, gauged

2,035

2.5

5,088

First floor

Particleboard flooring

544

8.0

4,352

First floor framing* kiln dried

1,505

2.5

3,763

Wall cladding

Timber weatherboard cladding* kiln-dried, dressed

2,646

9.5

25,137

Brick veneer

13,780

6.7

92,326

Fibre-cement sheet

2,940

9.4

27,636

Roof cladding

Steel roofing

1,048

34.8

36,470

Concrete tile roofing

10,350

0.81

8,384

Insulation

Glasswool insulation

294

30.3

8,908

Internal linings

Plasterboard linings

4,518

6.1

27,560

* Timber treatment not allowed for in embodied energy figure.

The table shows that the weight of materials used in construction can have an impact on relative embodied energy. For example, per kilogram of material, steel roofing has an embodied energy around 43 times greater than concrete roof tiles, but because the weight of steel required for a roof is far less than the weight of concrete tiles, the comparative embodied energy of a roof-lot of steel reduces to about 4 times greater than concrete roof tiles.