単価表の単価を労務・材料・機械費に分解する

Locate the nearest schedule item to the work in hand and read its description against the specification: the grade, the thickness, whether centering and shuttering are inside the item or billed separately, whether carriage is included.

理由: Most rate arguments are really description arguments. Two people agree on the cost of concrete and disagree about whether the item was supposed to include the formwork, and no amount of analysis settles that. Reading the description first tells you whether you are analysing a rate or discovering a missing item.

Expand one unit of the item into its constituents: the materials and their wastage allowance, the trade and helper hours to place them, and the plant hours the method needs. Adjust the assumed method where your site does it differently, and leave a note saying so.

理由: This step is where an inherited norm meets a real site, and the mismatch is worth finding now. A norm that assumes machine mixing on a job doing hand mixing will be wrong in the labour line and right in the material line, and only an opened analysis shows you which half to trust.

Build the labour rate per trade from the wage you pay plus what sits on top of it: the statutory contributions, the site allowances, the non-productive time you carry. Use the minimum wage notified for the state as a floor rather than as the answer.

理由: Labour is where a schedule rate ages fastest and where a contractor's own figure is genuinely better information than a published one. It is also the constituent most often priced at the bare wage, which quietly removes the contribution and allowance cost from every item in the estimate at once.

Store the analysis as a named assembly so the next bill can use it, and keep the contractor's profit and overheads as a percentage on the direct cost rather than absorbing it into the constituent prices.

理由: A tender is often accepted at a percentage above or below the estimated rates, and an assembly whose profit line is visible can be re-quoted at a different percentage in one move. One whose profit is spread through the material prices has to be rebuilt from the beginning, and usually is not.

Compare the analysed rate with the schedule rate for the same item and look at the constituents rather than the totals. Note which constituent carries the difference: material price, labour, plant, or the percentage on top.

理由: A gap in the material line usually means the schedule is out of date and is an argument you can win with quotations. A gap in the labour line usually means the method differs and is an argument you win with the analysis. Knowing which one you have before the meeting decides how it goes.