Types of Steel Bars: How to Choose the Correct Steel Bars for Your Building

Knowing the types of steel bars helps you choose the right reinforcement for your house or building. Steel bars (rebar or saria) give concrete the strength it lacks in tension. However, not every bar suits every job. This guide explains the main types of steel bars used in Pakistan, where each one is used, and which is best for house construction.

Before buying, check today’s saria price for the grade you need.

Main Types of Steel Bars

1. Plain (mild steel) bars

Plain bars have a smooth, round surface. Because they have no ribs, they grip concrete poorly. For this reason, builders now use them only for special jobs, such as dowels at expansion joints where the bar must slide, or for light non-structural work. They are not suitable for the main reinforcement of a building.

2. Deformed steel bars

Deformed bars have ribs rolled onto their surface. These ribs lock the bar into the concrete, so the steel and concrete work together. As a result, deformed bars are the standard reinforcement for columns, beams, slabs and foundations. Read more in deformed vs plain steel bars.

3. TMT (thermo-mechanically treated) bars

TMT bars are deformed bars that are water-quenched straight after rolling. The process gives them a hard outer layer and a softer, ductile core. Consequently, they combine high strength with good bendability. Most modern deformed bars in Pakistan are made this way. See the advantages of TMT bars.

4. Cold twisted deformed bars

Cold twisted bars get their strength by being twisted cold after rolling. They were common in the past, but TMT bars have largely replaced them because TMT bars are more ductile. For a comparison, read TMT vs cold twisted steel bars.

5. Coated bars (epoxy-coated and galvanized)

In very corrosive places, such as marine structures, engineers sometimes specify bars with an epoxy or zinc (galvanized) coating. These are special products for specific designs. For most buildings, however, good concrete cover gives the steel enough protection.

Grades of Steel Bars

Besides the type, every deformed bar has a grade, which tells you its strength. In Pakistan, the common grades to ASTM A615 are:

For details, see different grades of steel bars.

Which Steel Bar Is Best for House Construction?

For a normal RCC house in Pakistan, the best choice is usually a deformed (TMT) bar in Grade 60, in the sizes your structural drawings specify. Here is why:

• It grips the concrete well because of its ribs.
• It is about 50% stronger than Grade 40, yet costs only slightly more.
• It has enough ductility for earthquake-resistant design.

Above all, follow your engineer’s drawings. The grade and bar sizes are part of the design, so never swap them without approval. To compare the two main grades, read Grade 40 vs Grade 60 steel.

How to Choose the Correct Steel Bars

1. Check the drawings for the grade, sizes and bar schedule.
2. Buy deformed, branded bars with the maker’s rolled-in marks.
3. Ask for the mill test certificate for each delivery.
4. Check the weight: kg per metre should be close to D² ÷ 162. See how to calculate the weight of steel bars.
5. Store bars properly until use. See how to store steel bars on site.

Good Practice When Fixing Steel Bars

• Clean off loose rust, mud and oil before the bars go into the formwork.
• Keep the concrete cover shown in the drawings, using proper cover blocks.
• Tie bars firmly so they do not move when the concrete is poured.

Steel Bars from Kamran Steel

Kamran Steel has manufactured deformed steel bars in Lahore since 1984. We supply Grade 40, Grade 60 and Grade 75 bars to ASTM A615 in sizes from 10 mm to 36 mm and standard 12-metre lengths. For a house, see how much steel a 5, 7 or 10 marla house needs, or contact our sales team for a quote.

Once your engineer has confirmed the bar sizes, our steel rate calculator shows what the steel will cost.

Related reading: The Importance of Reinforcement Bars in Modern Construction · Top 10 Questions Engineers Ask When Choosing Steel Bars