Dimensions / Building materials / Rebar / 10M rebar
10M is Canada’s smallest common CSA G30.18 bar: 11.3 mm in diameter with 100 mm² of steel, weighing 0.785 kg/m (0.528 lb/ft), so a 6 m bar is 4.71 kg. The name is not the size: it is neither a Ø10 bar (78.54 mm²) nor a Ø12 (113.1 mm²), and Alberta substitutes it for #4, which has more steel. CBSA gives the standard lengths as 6, 12 and 18 m; stores sell 3 m and 6 m. In flat ICF walls NBC Part 9 laps 10M 450 mm and sets vertical bars 400 mm apart above grade; Ontario’s MTO bends it round a 60 mm pin at 400W and 70 mm at 400R.
| Diameter, area (CBSA, Russel) | Mass (Alberta, Russel) | Lap in flat ICF walls (NBC 2020) |
|---|---|---|
| 11.3mm100 mm² | 0.785kg/m0.528 lb/ft | 450mm |
Sources: CBSA, Russel Metals, NBC. Checked October 2026.
10M verticals in an ICF wall, a Part 9 lap and a 90° hook on a 400W bar are filled in. Enter your run, spacing, bars, lap and bend; each check follows a figure or rule on this page.
Weights are theoretical: a CSA bar’s mass is its nominal area times the density of steel, whatever the grade.
6000 mm less 75 mm clear at each end, at 400 mm, takes 15 10M bars with one at each end; you have 15. At 0.785 kg/m the 15 bars of 3 m weigh 35.3 kg, 2.355 kg each.
A 6 m wall with 10M verticals at 400 mm, as NBC Part 9 sets them in ICF walls above grade, in 3 m bars.
NBC 9.3.1.1.(4) laps 10M bars 450 mm in flat insulating concrete form walls; your 450 mm lap is enough. Other walls and slabs take their laps from the design under CSA A23.3.
NBC 2020 9.3.1.1.(4) laps 10M 450 mm in flat ICF walls; the pin and tail are an example.
Ontario MTO bends 400W 10M bars round a pin of at least 60 mm, and a 90° hook runs on 12 bar diameters, 135.6 mm; your 60 mm pin and 140 mm extension meet both.
MTO SS112-1 bends 400W round a 60 mm pin and 400R round 70 mm; a 90° hook runs on 12 bar diameters.
Selling 10M bar? Photograph a bundle tag and a bar end, mark the size, grade, length and rolled marks in SizeMarker and send it with your quote.
Mark a photoGovernment documents, mills and two retailers; masses are theoretical.
| Source | Size | Mass; length | Other |
|---|---|---|---|
| CBSAThis page | 10M, 11.3 mm | Standard lengths 6 m (20 ft), 12 m (40 ft), 18 m (60 ft) | Grades 400R, 400W, 500W, 600W; the 2021 edition dropped 500R |
| Russel Metals | 10M, 100 mm² | 0.785 kg/m, 0.528 lb/ft | 15M 200 mm², 1.570 kg/m |
| Alberta Transportation2022 | 10M | 0.785 kg/m | Substitute for #4; bridges use 15M and larger |
| AltaSteel | 10 to 45 mm | 6–20 m; bundles of 3.0–5.0 t | 400W, 400R, 500W, GR60; cites G30.18-09 |
| ArcelorMittal Long Products Canada | 10M to 55M | 15–60 ft; 10,000 lb bundles | 400R / 400W |
| Gerdau | 10MM | 0.785 kg/m | Rolled at Cambridge, Ontario (10M–25M) |
| Pittini Ferriere Nord | 10M and 15M coils | Yield 425–550 MPa, tensile 565 MPa or more | Rolled mark FN 10 W400 |
| Vieira Concrete SuppliesRetailer | 10M | 3 m (~10 ft) $6.30; 6 m (~20 ft) $11.30 | No grade printed |
| Star Building MaterialsRetailer | Sold as “10mm” | 6 m, 10.5 lb as printed | Also 3 m and 30 in pieces |
Sources: CBSA · Russel Metals · Alberta Transportation · AltaSteel · ArcelorMittal · Gerdau · Gerdau · Pittini · Vieira Concrete Supplies · Star Building Materials
Part 9 sends other reinforced concrete to Part 4 and CSA A23.3; these are the flat insulating concrete form (ICF) wall rules.
| Item | Rule |
|---|---|
| Laps in flat ICF wallsPart 9, 9.3.1.1.(4) | 450 mm for 10M, 650 mm for 15M |
| Dowels to the footing9.15.4.4 | 10M at most 600 mm apart, or 15M at 1.2 m |
| Horizontal bars, ICF foundation walls9.15.4.5 | One 10M within 300 mm of the top, then 10M at 600 mm; 30 mm cover from the inside face |
| Vertical bars, 150 mm ICF foundation wallsTable 9.15.4.5.-A | 10M at 400 mm for 1.35 m of backfill, 10M at 250 mm for 2.2 m |
| Above-grade ICF walls9.20.17.2.(2) | 10M verticals at 400 mm |
| Openings 600 mm to 3 m wide | One 10M at the top and one at the bottom |
| Concrete block foundation walls | Bond beams take at least one 15M |
Sources: NBC
Bridge practice under CSA S6, which MTO says meets the RSIC manual too.
| Item | 400R | 400W or 500W |
|---|---|---|
| Bending pinMTO SS112-1 | 70 mm | 60 mm |
| 90° hook | Extension 12 bar diameters; overall 180 mm | The same |
| 180° hook | Extension 4 bar diameters; overall 140 mm, J 90 mm | Overall 130 mm, J 80 mm |
| Stirrups and ties | Pin 45 mm; overall 100 mm | The same |
| 15M pin, for comparison | 100 mm | 90 mm |
Sources: Ontario MTO · Ontario MTO
| Bar | Diameter | Area | Mass |
|---|---|---|---|
| 10MCSA G30.18 | 11.3 mm | 100 mm² | 0.785 kg/m |
| Ø10GB 1499.2-2024 | 10 mm | 78.54 mm² | 0.617 kg/m |
| Ø12GB 1499.2-2024 | 12 mm | 113.1 mm² | 0.888 kg/m |
| #4US; Alberta pairs it with 10M, though it has 1.29 times the area | 12.7 mm | 129 mm² | 0.994 kg/m |
| #3US | 9.5 mm | 71 mm² | 0.560 kg/m |
| 15MCSA | 16.0 mm | 200 mm² | 1.570 kg/m |
Sources: CBSA · Russel Metals · GB 1499.2-2024 · Ohio DOT · Alberta Transportation
| Item | Figure |
|---|---|
| Mass from sizeArcelorMittal; our calculation | Nominal area × 7850 kg/m³: 100 mm² gives 0.785 kg/m |
| GradesCBSA | R for general use; W where welding, bending or ductility matters |
| StandardsNBC 2020 | Bars to CSA G30.18:21; design to CSA A23.3:19, construction to CSA A23.1:19 |
| BridgesAlberta Transportation | 10M only in drain troughs and slope protection |
| In the check aboveOur calculation | (6000 − 2 × 75) ÷ 400 = 14.6, so 14 spaces and 15 bars; 15 × 3 m × 0.785 = 35.3 kg, 2.355 kg a bar and 4.71 kg for 6 m; lap 450 mm; 400W pin 60 mm, 90° extension 12 × 11.3 = 135.6 mm |
Sources: ArcelorMittal · CBSA · NBC · Alberta Transportation
11.3 mm in diameter with 100 mm² of steel (CBSA, Russel Metals). The 10 is a designation number, not millimetres: a true Ø10 bar has 78.54 mm².
0.785 kg/m (0.528 lb/ft), so 2.355 kg for a 3 m bar and 4.71 kg for 6 m; Star Building Materials prints 10.5 lb for its 6 m bar.
No. #4 has 129 mm² and Ø12 113.1 mm², against 100 mm² for 10M. Alberta lets 10M stand in for #4 in bridge design, but by area they are different bars.
450 mm in flat insulating concrete form walls built to NBC Part 9 (9.3.1.1.(4)); 15M laps 650 mm. Other work takes its laps from the design under CSA A23.3.
CBSA lists 6, 12 and 18 m (20, 40 and 60 ft) as standard; Canadian stores sell 3 m and 6 m, and AltaSteel cuts 6 to 20 m.
Ontario’s MTO drawing SS112-1, bridge practice under CSA S6, bends 10M round a 70 mm pin at 400R and 60 mm at 400W or 500W, with hooks of 12 bar diameters at 90° and 4 at 180°.
Buyers ask for the CSA size and grade (10M 400W or 400R to G30.18:21), the cut length, the theoretical mass, the rolled marks, the bundle weight, and whether the bar may stand in for a #4 or a Ø12. Mark the real bars, a cut end and the bundle tag on your own photo in SizeMarker, as in the picture at the top, and send one product card for WhatsApp or WeChat.
