Concrete volumes and reinforcement quantities for the structural elements you survey.
Foundation, roof and structure. 5 questions answered below, each with the arithmetic behind it and the limits of what the tool decides. Open the Concrete and Structural Takeoff tool.
A structural takeoff is a schedule, not a design. Slabs, beams, columns, footings and walls are each measured from their own dimensions, and the totals roll up by material so the steel order and the concrete order are separate documents. The tool holds that shape because a concrete frame is bought as materials, not as elements. What it will not do is decide the size of anything. A beam is measured at the depth it was designed to, a slab at its designed thickness, and the reinforcement counted in the diameters and lengths on the bar schedule. Those are the inputs. The output is the concrete volume, the formwork area where you ask for it, and the reinforcement weight by diameter, which is what a supplier and a fixer both work from.
A slab ten metres by eight at a hundred and fifty millimetres is twelve cubic metres. Two beams six metres long at three hundred by six hundred add two and two tenths cubic metres. Six columns three metres high at three hundred by three hundred add one and six tenths. The total is close to sixteen cubic metres of concrete, and at a one to one and a half to three mix that is roughly five cubic metres of cement, seven and a half of sand and fifteen of aggregate, in bags and tonnes for your market. Reinforcement comes separately: twenty five bars of sixteen millimetre at seven metres, plus thirty of twelve millimetre at five metres, converted to kilogrammes by bar mass and summed by diameter, so the steel order is a schedule a fabricator can cut from.
It measures concrete and reinforcement for the elements you describe. Each slab, beam, column, footing or wall is entered with its own dimensions, and the quantities roll up by material. Reinforcement is counted by bar diameter, length and number, then converted to mass using the unit weight of that bar size, which is how a steel order is placed. What it does not do is decide the dimensions: those come from the structural design, and the schedule assumes they are already fixed.
From you, and from the drawing you are reading. The length, breadth and depth of each element are entered as they appear on the design, and the bar schedule supplies the diameters and lengths for reinforcement. The tool does not scale a drawing or infer a section from a span, because a takeoff built on inference is a takeoff that cannot be checked. Where a dimension is missing, it is reported as missing so the gap is closed on the drawing before anything is ordered.
No. It is a material schedule, which is a different document from a design. Sizing members, calculating loads, checking deflection and detailing reinforcement are engineering work, and the tool assumes that work is done. The value it adds is turning a finished design into quantities and an order that can be placed, checked and audited, which is where most of the arithmetic and nearly all of the clerical error live.
From the mix you specify, in proportions by volume, converted to the bag size sold in your market. A one to one and a half to three mix and a one to two to four mix give noticeably different cement content for the same concrete volume, so the mix is an input rather than a default. Sand and aggregate are then expressed by volume or by tonne, and cement by bag, because that is how each is bought at a merchant in most markets.
Yes, and they should be, because a frame is placed and poured in sequence rather than in one operation. Each element keeps its own line with its own dimensions and quantity, and the materials roll up across the whole set. That way a slab can be ordered for one pour and columns for another, while the totals still tell you what the whole frame needs. Mixing everything into a single volume loses the sequence and makes a partial pour impossible to price.