Is Contractor Calc Pro really free?
Yes — the Core Pack (10 calculators) is completely free. There are no ads and no subscription. The Carpentry Pack is an optional one-time Pro upgrade that unlocks 5 additional tools: Board Feet, Framing, Concrete, Roof Pitch, and Roof Area.
Does it work without an internet connection?
Yes. All 20 calculators work fully offline. There are no server calls, cloud accounts, or login requirements. Once downloaded, the app works anywhere — on the roof, in the crawlspace, or anywhere else with no signal.
Which building codes does the app reference?
The app references IRC 2021 for stair and insulation requirements, NFPA 211 for chimney and flue sizing, and SMACNA tables for gutter and downspout sizing. The Tap & Drill chart covers UNC, UNF, Metric, and NPT thread standards. Always verify results against your local adopted code amendments.
How do I restore my Carpentry Pack purchase on a new device?
Open Contractor Calc Pro, go to any Pro-locked calculator, and tap "Restore Purchases." As long as you're signed into the same Apple ID used for the original purchase, your Carpentry Pack will be restored at no additional charge.
Can I save and share my calculation results?
Yes. Every calculation is automatically saved to Recent Calculations. You can also manually save results with a custom label. Use the iOS share sheet to send any result via Messages, email, or any other app.
How accurate are the cost estimates?
Cost estimates are based on average regional material prices and are intended as a planning reference only. Prices vary significantly by region, supplier, and market conditions. Always confirm with your local supplier before finalizing a bid.
Something looks wrong with a calculation. What should I do?
Email us at
support@zima-logistics.com with a description of the inputs you used and the result you expected. We respond within 1–2 business days and push fixes quickly.
What iOS version does the app require?
Contractor Calc Pro requires iOS 16 or later. It runs on iPhone and is optimized for all current iPhone screen sizes.