Concrete frame cost: what makes up the price of one m³, and when precast pays off better than casting on site
Concrete frame cost is built from the same components as any price in construction: materials, labour, and overheads and profit. A rule of thumb well known in the industry says that each of them is roughly a third of the price, but in the frame the ratio changes from element to element, mainly with the amount of formwork. I have experience in pricing concrete frames and in breaking m³ prices down into inputs, from the cost calculations of the final project of my construction management studies to tenders.
The rule of thirds, and what the price of one m³ includes
In an Israeli bill of quantities (BOQ), the m³ price of a concrete element usually includes the concrete, the formwork and the pour, while the rebar is measured in a separate item, in tonnes. So when you compare concrete frame cost between quotes, make sure you are comparing the same scope. Within the price there are four components: materials (concrete, timber for the forms and consumables), labour (formwork carpenters and pouring), plant (pump and crane), and overheads and profit. How to break each one down into hours and materials is shown on the construction inputs and resources page.
A worked example: one m³ of column, from my final project's calculation
The input data come from the cost calculation I prepared for my final project, at 2017 prices, for illustration only: a column with a 22 by 40 cross-section, which means 14.08 m² of formwork per m³; timber at 13.33 shekels per m² after ten uses and waste; concrete at 320 shekels per m³ with 4% waste; a formwork carpenter's hour at 55 shekels and a pouring hour at 70.
| Component | Calculation | Shekels |
|---|---|---|
| Timber for the forms | 14.08 × 13.33 | 188 |
| Formwork consumables | 14.08 × 6 | 84 |
| Concrete including waste | 320 ÷ 0.96 | 333 |
| Pump and plant | 20 + 50 | 70 |
| Formwork labour | 14.08 hours × 55 | 774 |
| Pouring labour | 1.6 hours × 70 | 112 |
| Direct cost | 1,562 | |
| Site overheads 14.5% and company overheads 10.3% | × 1.145 × 1.103 | 1,973 |
| Profit, 10% of the price | ÷ 0.9 | 2,192 |
Split by thirds: materials are about 28% of the price, labour about 40%, plant about 3%, and overheads and profit about 29%. Labour is heavier than a third because of the 14 m² of formwork. In a calculation like this it is easy to forget the timber and the consumables; in the example they come to about 272 shekels together, about 17% of the direct cost.
Slab vs column per m³: formwork decides
With the same input data, a 20 cm slab needs 5 m² of formwork per m³ instead of 14.08. The result:
| Figure | Column 22/40 | Slab 20 cm |
|---|---|---|
| m² of formwork per m³ | 14.08 | 5 |
| Direct cost | 1,562 | 887 |
| Price with overheads and profit | 2,192 | 1,245 |
| Materials share | about 28% | about 34% |
| Labour share | about 40% | about 31% |
| Plant share | about 3% | about 6% |
| Overheads and profit | about 29% | about 29% |
In the slab the ratio is very close to thirds. In the column, and in thin walls, labour pulls upwards. So a single average price per m³ for the whole frame is misleading: the mix of columns, walls and slabs decides it.
Concrete frame cost today: what you see, and why not to copy a number
Consumer price comparison websites currently show ranges, in shekels, of about 1,500 to 2,000 per m³ of column or beam, including concrete and without rebar. These price lists are undated and meant for small jobs, so they give an order of magnitude, not a price for a project. Since 2017 the construction inputs index, Israel's official index of building input costs, has gone up, and the real price is set in the quote, according to scale, access and the construction programme. Index linkage is explained on the index linkage and VAT page.
Precast vs cast in place: when each one pays off
| Consideration | In favour of precast | In favour of casting on site |
|---|---|---|
| Size and repetition | Many identical elements | A small project or varied shapes |
| Design in advance | Design frozen before production | Changes expected along the way |
| Access to the plot | Room for a heavy crane and trucks | A tight plot |
| Construction programme | Time pressure on the frame | No special pressure |
According to an article from 2018, a set of industrialised forms for a building cost about one million shekels at the time, so it pays off when several identical buildings are built. The logic is simple: if a form costs a fixed sum and each use saves a fixed sum, the break-even point is the fixed sum divided by the saving per use. More on industrialised methods on the industrialised construction page.
A common combination is a frame cast on site with precast hollow-core slabs. In the specification of my final project, the topping over the slabs was measured by area with the thickness stated, the infill pours by theoretical volume, and the filling of the joints between the slabs as a separate item; a strip wider than 50 cm is measured as an ordinary slab. When each part is measured this way, quotes can be compared even when only part of the frame is precast.
Some contractors quote concrete frame cost per built m². That is handy for a first comparison, but it hides the mix: a building with many walls of protected rooms (the mamad, the reinforced safe room in every Israeli flat), retaining walls or a basement costs more per m², even when the m³ price is the same. So it is worth asking for both numbers: a price per m³ by element, and the number of m³ per built m².
A quick check for a quote: if, in the price of one m³ of column, the labour share is lower than the materials share, ask how the formwork was calculated.
A price per m³ of concrete says little without a quantity takeoff that separates foundations, walls, columns and slabs. A quantity surveyor who holds that breakdown can check whether the total price of the frame is reasonable, and the quantity takeoff becomes a tool in negotiation.
Frequently asked questions
Is the rebar included in the m³ price?
Usually not. In an Israeli BOQ the rebar is a separate item in tonnes, so it is compared separately.
Why does one m³ of column cost more than one m³ of slab?
Because of the formwork: almost three times as many m² per m³, and with them, formwork carpenter hours.
Where do the overheads and profit come from?
From a monthly calculation of the site and from the company's expenses, with profit on top. See site overheads and contingency allowance, insurance and bank guarantees.
Who can break down a frame quote for me?
A quantity surveyor for construction projects who knows contractor pricing, by inputs, quantities and programme.
Have a project? Tell me briefly what the project is and what already exists. When the project is a good fit, I usually reply with focused questions and a written quote.
Contact me for a quote* Created with AI for marketing, for illustration only. Not reviewed by Yaakov Avital and not professional advice. Every project must be checked on its own by a professional quantity surveyor and an engineer.