20 mm rebar weight
2.470 kg/m · 1.660 lb/ft
20 mm rebar has a nominal diameter of 20 mm and a cross-sectional area of 314 mm².
20 mm rebar weight calculator
Weight of standard bar lengths
| Bars | 6 m (kg) | 12 m (kg) |
|---|---|---|
| 1 | 14.8 | 29.6 |
| 10 | 148.2 | 296.4 |
| 50 | 741.0 | 1,482.0 |
| 100 | 1,482.0 | 2,964.0 |
Bars per tonne
| Bar length | Bars per tonne |
|---|---|
| 6 m | 67.5 |
| 9 m | 45.0 |
| 12 m | 33.7 |
One tonne of 20 mm rebar is 405 m per tonne. Use this to turn a weight on a delivery note into a bar count.
How the weight is calculated
Area = π ÷ 4 × 20² = 314.2 mm². Weight per metre = area × 7850 kg/m³ = 314.2 × 10⁻⁶ m² × 7850 = 2.466 kg/m. The d² ÷ 162 rule gives 400 ÷ 162 = 2.469 kg/m.
Deformed bars and TMT bars are sold by nominal diameter and nominal mass; the ribs are already allowed for, and standards accept a small mass tolerance per bar. See the rebar weight formula guide.
20 mm rebar per square metre of slab
Weight of 20 mm rebar in a slab or wall for common spacings, for one layer in one direction and for bars both ways. Add laps, hooks and chairs on top.
| Spacing (centres) | One direction (kg/m²) | Both directions (kg/m²) |
|---|---|---|
| 100 mm | 24.70 | 49.40 |
| 125 mm | 19.76 | 39.52 |
| 150 mm | 16.47 | 32.93 |
| 200 mm | 12.35 | 24.70 |
| 250 mm | 9.88 | 19.76 |
| 300 mm | 8.23 | 16.47 |
Compared with nearby sizes
| Bar | kg/m | lb/ft | vs this bar |
|---|---|---|---|
| 14 mm rebar | 1.210 | 0.813 | −51 % |
| 16 mm rebar | 1.580 | 1.062 | −36 % |
| 20 mm rebar | 2.470 | 1.660 | — |
| 25 mm rebar | 3.850 | 2.587 | +56 % |
| 28 mm rebar | 4.830 | 3.246 | +96 % |
Bars of this size are typical main reinforcement for beams, columns, footings and retaining walls. The nearest US bar is #6 rebar (19 mm, 2.235 kg/m).
Frequently asked questions
What is the weight of 20 mm rebar per metre?
20 mm rebar weighs 2.470 kg/m (1.660 lb/ft). By the rule of thumb d squared over 162: 20 x 20 / 162 = 2.469 kg/m.
How much does a 12 m bar of 20 mm rebar weigh?
29.64 kg (2.470 kg/m × 12 m). A 6 m bar weighs 14.82 kg.
How many 12 m bars of 20 mm rebar are in a tonne?
About 33.7 bars, or 405 m per tonne.
What is the US equivalent of 20 mm rebar?
The nearest US bar is #6 rebar (19 mm, 2.235 kg/m). Check the steel area in the design before substituting one for the other.
How is the weight of 20 mm rebar calculated?
Area = π ÷ 4 × 20² = 314.2 mm². Weight per metre = area × 7850 kg/m³ = 314.2 × 10⁻⁶ m² × 7850 = 2.466 kg/m. The d² ÷ 162 rule gives 400 ÷ 162 = 2.469 kg/m.
How much 20 mm rebar is needed per square metre at 150 mm spacing?
One layer at 150 mm centres needs 16.47 kg/m² in one direction, 32.93 kg/m² for bars both ways, plus laps.
Other bar sizes
6 mm rebar · 8 mm rebar · 10 mm rebar · 12 mm rebar · 14 mm rebar · 16 mm rebar · 25 mm rebar · 28 mm rebar · 32 mm rebar · 40 mm rebar · 50 mm rebar
Full rebar weight chart · Steel weight calculator
Data adapted from Wikipedia, "Rebar" (CC BY-SA 4.0).