Steel Rebar (Reinforcement Bars)

What it is

Kitovu keeps steel reinforcement bars, called nondo in Tanzania, in its stock in Zanzibar and sells them by the tonne at TZS 2,700,000. On site they are cut to length, bent to shape and wired together into cages for columns and beams or into mats for slabs and footings, and then concrete is poured around them. Concrete takes squeezing well but cracks when it is pulled; the steel inside carries that pull.

The bar diameters on hand, the steel grade and the bar length are not in Kitovu’s records yet, so this card does not state them. Send the sizes from your structural drawing on WhatsApp and the reply will say which of them are in stock.

What arrives can be checked against the drawing. Bars are specified by diameter in millimetres and by grade. BS 4449, the UK specification for reinforcing bar, sets three grades, B500A, B500B and B500C, with the same 500 MPa yield strength; they differ in how far the steel stretches before it breaks. Shops in Dar es Salaam also list a lower BS300 grade, so check the grade written on the delivery paperwork as well as the diameter. Sizes, grades and the checks on delivery are set out on the rebar page.

From tonnes to bars

Rebar is weighed, not counted, when it is sold by the tonne. Divided by 1,000, Kitovu’s tonne price gives TZS 2,700 for each kilogram of steel (our calculation). BS 4449 gives the mass of each bar size per metre, and 40 ft (12.19 m) is the bar length Lodhia sells in Dar es Salaam, as listed on rebar prices in Tanzania. For bars of that length (our calculations):

From tonnes to bars

Diameter	Mass per metre	One 40 ft bar	Bars in one tonne
8 mm	0.395 kg	4.82 kg	about 207
10 mm	0.617 kg	7.52 kg	about 133
12 mm	0.888 kg	10.83 kg	about 92
16 mm	1.578 kg	19.25 kg	about 52

The length of the bars in Kitovu’s stock is not confirmed, so treat the last two columns as a guide and ask before counting bars for an order.

For an order, copy the bar schedule from the drawing: each diameter with its count of bars or its weight in kg. Whether single bars are sold, and at what price, is answered on WhatsApp.

In the concrete

Steel strengthens the concrete only where the design puts it, with the cover the drawing asks for on every side. A slab’s bottom mesh is lifted off the formwork on chairs during the pour; the plastic rebar chairs in Kitovu’s stock are made for that, and cement for the concrete itself.