The lines that blow your budget aren't the ones you priced

You priced the job. The rates look right, the total looks fair, and then two months in the budget's gone and you can't point to a single mistake. Nobody underpriced the brickwork. What got you was the stuff that never got its own line in the first place.

The gaps that eat a budget

Prelims are the usual one. Site set-up, welfare, supervision, scaffold hire for the length of the job, all the running costs that sit underneath the actual building work. Roll them into a single guessed figure and they quietly run over every time, because they scale with time on site, not with the work itself, and time on site is the one thing that never goes to plan.

Provisional sums are the second trap. A number sat in the tender for something nobody has priced properly yet, ground conditions, an existing structure, a specification that's still being decided. Treat it as a placeholder and move on, and it turns into a real cost with no real number behind it the day it's confirmed.

Access is the quiet one. A tight site, a shared road, restricted hours, a lift that has to be hired because there's nowhere to store materials at ground level. None of it shows up in a rate for brickwork or first fix. It shows up in the plant hire invoice three weeks in.

Price them up front, not as they land

Each of these needs its own line, its own quantity and its own rate, not a percentage tacked onto the bottom of the tender. Measured properly, to NRM2, prelims and provisional sums sit where the client and you can both see them, so nobody's surprised when they move.

What we do with it

Send your drawings and we build the whole job this way, prelims and provisional sums identified and priced as their own items, not folded into a total nobody can question. You get a breakdown that shows exactly where the risk sits before you ever step on site.

Send your drawings and we'll turn them into a client-ready estimate. See a sample estimate to see exactly what you'd be handing over.

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