Senior editor
Sam Johnson
Sam Johnson is 38 and has spent 15 years in the concrete and construction niche. Fifteen years is long enough to learn that most jobs do not fail on the pour day. They fail weeks earlier, on a napkin, when somebody guesses at yardage or forgets that a short load carries a fee.
That is the problem this site exists to solve. Sam maintains every formula, worked example and default price here, and the rule he holds to is simple: a number without its assumption is useless to the person holding the tape. So each calculator shows its math in words, states what it assumes, and lets you replace any price with your own quote.
Writing came alongside the trade work. Years of writing articles about materials and estimating taught him that the clearest explanation is usually the shortest one, and that readers deserve to be told where a figure came from rather than asked to trust it.
How a number gets published here
Formula changes require a published industry or manufacturer source and a hand-checked example. Default prices are planning figures, reviewed quarterly and kept editable because local quotes always win.
The full breakdown of which figures are published standards and which are editable site assumptions lives on the methodology page, with the date each price was last reviewed.
Away from the calculators
Away from the numbers, writing and building things are what Sam does for his own enjoyment, which is a large part of why this site reads the way it does rather than like a spec sheet. Two children at home keep the schedule honest and the explanations short.
Sources we return to
These are the starting points for material definitions, placement guidance, control joints and packaged-concrete yields. Page-level assumptions remain labeled and editable.
What this site does not claim
Concrete Calculators does not replace a local supplier, building official, licensed engineer or site-specific design. Sam's job is to make planning math transparent enough that you can check it before a truck is dispatched.