About ContractorCalcPro
Who Built This Site
My name is Ray Okafor. I've been in residential construction for 14 years — starting as a laborer straight out of high school, working my way up to framing crew lead, then spending the last seven years as an estimator and project manager for a mid-size general contracting firm in the Dallas-Fort Worth area.
Over that time I've estimated hundreds of residential projects: additions, remodels, new builds, decks, concrete flatwork, roofing tear-offs and replacements. I've also seen what happens when homeowners show up to a contractor meeting with zero understanding of materials math — they get oversold, they miss obvious errors in proposals, and they have no way to push back when a bid seems high.
ContractorCalcPro started as a collection of the formulas I use on the job every day. Concrete volume, roofing squares, lumber coverage, deck cost breakdowns — the math isn't complicated, but it's scattered across a dozen different trade references that most homeowners have never read. I put them in one place, with plain-English explanations of what you're calculating and why it matters.
What This Site Covers
ContractorCalcPro provides free material and cost calculators for construction, renovation, and DIY projects:
- Concrete Calculator — cubic yards for slabs, footings, columns, and steps
- Roofing Calculator — squares of shingles needed, adjusted for pitch and waste
- Lumber Calculator — board feet, linear feet, and stud counts for framing
- Flooring Calculator — square footage with waste factor for tile, hardwood, and LVP
- Mulch Calculator — cubic yards for landscape beds at any depth
- Pool Salt Calculator — salt additions for saltwater pool systems
The guides section covers how to actually read and use the numbers these calculators produce — understanding concrete mix types, how to buy lumber at the yard without getting the wrong grade, and how to compare contractor bids using real unit cost benchmarks.
How the Numbers Are Sourced
Every formula on this site comes from the same sources I use professionally: the International Residential Code (IRC), the National Design Specification (NDS) for wood construction, RS Means cost data, and manufacturer specifications for materials like roofing shingles and concrete mixes.
Cost estimates I publish reflect current national averages from published trade sources — RS Means, HomeAdvisor aggregates, and RSMeans contractor data updated annually. Regional prices vary significantly, and I note this on every cost-related calculator and guide. The estimates are a baseline for conversations with local contractors, not quotes.
I update the cost data annually and refresh material specs when I see significant market changes — like the lumber price swings of 2021–2022, which required multiple updates to keep the lumber guides accurate.
A Note on Estimates vs. Quotes
These calculators give you material quantities and rough cost ranges — not contractor quotes. A professional estimate accounts for site conditions, local labor rates, material availability, permit requirements, and dozens of other factors that no calculator can capture. Use these tools to prepare for contractor conversations and to reality-check bids, not to skip the conversation altogether.
For any project above a few hundred dollars, get at least three quotes from licensed contractors before committing. The calculation tools here will help you understand what you're being quoted — and whether the numbers make sense.
Contact
Spotted an error, have a question about a formula, or want to see a calculator that isn't here yet? Use the contact form. I check it regularly and I'm happy to explain the math behind any result.