About

I'm Sam Redfield, and I review every formula on this site. I spent the last decade writing about residential construction and DIY renovation for trade publications in North America and Europe — the kind of coverage where you sit through a lot of contractor interviews and read a lot of building code before a story ever gets filed.

Somewhere in there I also built three decks of my own — one good, one I'd redo the joist spacing on if I had the chance, and one that's still standing mostly out of stubbornness. I've tiled a bathroom I'd rather not talk about. None of that makes me a structural engineer, and I'm not pretending to be one. It does mean I know exactly where a calculator like this one can save you a wasted supply run, and exactly where it can't replace a local permit office or a licensed tradesperson.

I review the formulas behind every calculator on this site quarterly, alongside the material prices they run on. When a formula is wrong, or a price has drifted, I want to know before you do — not after you've bought the wrong number of boards. You can see exactly what that review process covers, and where the numbers come from, on our Methodology page.

If you spot something that looks off — a price that's moved, a permit threshold that's changed, a formula that doesn't match what you found on-site — I'd genuinely like to hear about it. Get it wrong quietly and it just sits there misleading the next person; get it flagged and it gets fixed at the next quarterly review.