Before now, concrete for building is mixed manually, and this, sometimes, results in poor mixture of cement with concrete, which produces poor quality job.
But with the cement prices ranging between N4, 000 and N4, 500 in many cities, quantity surveyors are recommending the use of ready mix in their bills of quantities.
The development has put pressure on the few companies that provide concrete such as Lafarge Readymix Nigeria Limited, the new subsidiary of Lafarge Cement. The firm’s trucks transport mixed concrete to the construction sites in major cities in the country.
The Guardian learnt that the complexities and logistics associated with the supplying of the product made some other cement manufacturing companies to jettison the business venture.
The Lafarge provides commercial ready-mix concrete product, targeted at providing products and services to building contractors, who need large volumes of already mixed concrete to ensure faster and quality execution of jobs.
Head, Corporate Communications, Lafarge Africa Plc, Ginikanwa Frank- Durugbor told The Guardian: “The rates for ready mix concrete are a function of the concrete grade, cost of input raw material – cement, aggregate (granite), sand and chemical admixture (which is direct function of distance and transport cost of aggregate from source to the batching plant site).
She explained that the aggregate prices might also vary by as much as 50 per cent between different locations. “Concrete grades range from C10 and C20 for non-structural application, to C25 to up to C50 for structural application. Aside the compressive strength classification, additional durability requirements like waterproofing, low heat, sulphate resistance will impact the pricing of concrete,” Frank- Durugbor said.
According to her, ready mix concrete offers builders’ diverse benefits. It ensures consistency in concrete quality – strength and durability, allows access to high specification capabilities that Lafarge offers, due to lack of same expertise level or capacity in the contractor’s team such as self-compacting concrete, water proof concrete, Low heat concrete for mass concreting, sulphate resistant concrete, early strength concrete and early strip concrete.
She stressed that the product is appropriate for sites with limited space for storage of materials or concrete batching; reduces wastes and pilferage on job sites and enhances housekeeping and improves health/safety conditions on job sites.
However, builders say the use of concrete mix increases the cost of construction while quantity surveyors said concrete mix is the best option for achieving quality and durable construction.
The President, Nigerian institute of Building (NIOB), Kunle Awobodu, said the ready mix concrete is more expensive but tolerable.
According to him, building materials such as cement, sand and granite have skyrocketed, making the production of concrete on sites a big issue.
Awobodu disclosed that the challenge builders have on ready mix concrete, include the delay in supply of the product and inclusion of 7.5 per cent Value Added Tax (VAT) on the product, which increases the price.
President of the Commonwealth Association of Surveying and Land Economy (CASLE), Mr. Olusegun Ajanlekoko, said ready mix concrete is a much better option for any major construction work. “It’s quality assured; it’s a very clean operation; its spread rate is higher than site mixed in-situ concrete mix. Even though a bit more expensive it’s reliable and requires less labour.
“Those who prefer in-situ site concrete mix are majorly small-scale contractors and for only residential and small scale projects.”
Ajanlekoko, a former president, Nigerian Institute of Quantity Surveyors (NIQS), noted that the bills of quantities prepared by quantity surveyors usually describe concrete mix as in-situ or in the alternative as precast concrete.
Another quantity surveyor and former chairman, NIQS, Lagos chapter, Mr. Jide Oke, explained, “ready mix concrete has always been around with us but they have been mostly used on difficult, inaccessible and sometimes water logged terrains. They are also used for high-rise building construction and engineering projects, where high quality of mix is expected.
“It is for projects where minimal human error is expected in concrete mix. They are recommended for projects when these quality precisions are required.”