Terms of Use

Last updated: March 23, 2026

By using HardHatCalc("the site"), you agree to these terms. If you don't agree, please don't use the site.

Estimation Only

All calculators on this site produce estimates for planning purposes. Results are based on published construction formulas and industry-standard references. They are not a substitute for professional engineering advice, architectural plans, or local building code compliance review.

Not Engineering Advice

This site is built by a web developer and IT researcher, not a licensed structural engineer or architect. The structural calculators (beam sizing, load calculations, truss pricing, deck capacity) provide rough estimates to help with project planning. They do not constitute engineering design or certification.

For any project involving load-bearing structures, foundations, or structural modifications, you must consult a licensed structural engineer in your jurisdiction. Building permits typically require stamped engineering drawings — calculator output does not satisfy this requirement.

Accuracy and Limitations

We make reasonable efforts to ensure calculator formulas are correct, but we do not guarantee accuracy. Results may vary due to:

• Material grade differences (lumber species, steel grade, concrete mix)
• Regional building code requirements
• Site-specific conditions (soil type, wind load, seismic zone)
• Supplier pricing variations
• Rounding and simplification in formulas

Liability Limitation

HardHatCalc and its operator (Dan Dadovic) are not liable for any damages, losses, or injuries arising from the use of calculator results. You use the tools at your own risk. Always verify results with qualified professionals before purchasing materials or beginning construction work.

Cost Estimates

Cost figures shown on this site are based on US national averages at the time each page was last updated. Actual costs depend on your region, supplier, material grade, labour rates, and market conditions. Cost estimates should be used as a starting point for budgeting, not as quotes.

Intellectual Property

The content, calculators, code, and design of this site are the property of Dan Dadovic. You may use the calculators freely for personal and commercial project planning. You may not copy, reproduce, or redistribute the calculator code, content, or design without permission.

Changes to These Terms

We may update these terms as the site evolves. Continued use of the site after changes constitutes acceptance of the updated terms.