About Us
What ProGrade Calculators Is
ProGrade Calculators publishes precision estimating tools and reference articles for post-hole, fence-post, deck-footing, and pergola-footing work. Every calculator is built against the structural-engineering and material-specification standards that working contractors are expected to know: the International Residential Code (IRC R507 for decks, R403 for footings), ASTM standards for concrete mix specifications, the American Wood Protection Association (AWPA) Use Category system for pressure-treated wood, and ASHRAE and NOAA frost-depth data by region.
We exist because the calculators we kept finding online were wrong about three specific things — they did not include the 10% waste factor every concrete delivery actually needs, did not adjust volume for the displacement of the post being set, and did not flag when a stated depth was below the frost line for the user's region. A calculator that gets any of these wrong puts the user a bag short, or sets a post that heaves out of the ground at first frost. We built the math the way it needs to be built.
Who This Is For
The articles and calculators are written for two readers, in this order. The first is the working contractor or fence and deck installer bidding a job who needs material quantities that account for site reality — uneven hole walls, soil displacement, the half-bag that always gets contaminated by rain — and needs them on the way to the supply yard, not at a desktop. The second is the residential do-it-yourselfer who has read enough to know the IRC exists but is not in a position to engage a structural engineer for a fence project, and needs to make code-aware decisions about depth, spacing, and footing diameter without guessing.
We are not the right site for the homeowner trying to decide whether to build a fence or a deck. We assume the project is already specified and the question is how to execute it correctly.
How the Calculators Are Built
Every estimator on the site applies the same rules. Concrete volume uses the standard 80-lb bag yield of 0.60 cubic feet, calculates the cylindrical hole volume net of the displacement of the post being set, and adds a 10% waste buffer rounded up to the next whole bag. Frost-line depths are sourced from state and municipal building-code references and the NOAA frost-depth dataset. Where a state has a range (Minnesota's 42 to 60 inches by county, for example) we display the range and recommend the higher value. Post-spacing recommendations follow the IRC R507.4 spans for deck applications and the AWPA UC categories for ground-contact treated lumber durability ratings. Cost estimates use ranges, not point values, because material and rental costs vary by region. Where we cite a dollar figure, we cite a range based on national big-box and rental-counter retail data, refreshed annually.
Editorial Standards
Every article on the site goes through the same process before publication. Code references are checked against the current published edition. Numbers are sourced or derived, never asserted — when an article gives a span or a depth or a cost, the underlying number is either taken from a citable standard or derived from documented physics. Articles open with the failure mode the article is preventing, run through the decision matrix or specification table that resolves it, and close with a bottom-line summary and the code references that govern the topic. We do not use exclamation points. We do not say "let's dive in." We do not pad word count.
What We Are Not
ProGrade Calculators is a reference and estimation site, not a substitute for any of the following. A licensed structural engineer when the project requires one — decks above thresholds set by IRC R507, retaining walls above grade-change thresholds, any structure attached to a primary residence in a high-wind or high-seismic zone, and any commercial application require an engineer's review and stamped drawings. A local building official whose jurisdiction sets the actual frost-line depths, footing requirements, and setback rules. A site visit, because soil type, water-table depth, frost penetration in any specific lot, and the presence of underground utilities all materially affect what the right depth, diameter, and material quantities actually are.
Contact
For corrections, source citations, content suggestions, or broader feedback, the editorial team can be reached at info@progradecalculators.com. We respond to inquiries within two business days. For broken-link reports or factual disputes, please include the article URL and the specific claim being questioned — it speeds up resolution.
