Terms of Service & Engineering Disclaimer

Last Updated: November 2026

By accessing and utilizing BoilerSizeCalculator.com (the "Site"), you agree to be bound by these Terms of Service. If you do not accept these terms, you must discontinue using our calculation tools, reference charts, and editorial guides immediately.

1. Informational & Preliminary Planning Purposes Only

All calculations, equations, sizing recommendations, and technical reference data published on this Site are provided strictly for preliminary planning, sizing estimation, and educational comparison.

They do not constitute a formal on-site hydronic, structural, or mechanical survey. A web-based tool cannot assess physical pipework routing, hydraulic resistance, local water hardness, flue terminal clearances, ventilation adequacy, or appliance condition.

2. Mandatory Professional Verification & Statutory Safety Regulations

Prior to purchasing heating appliances, ordering cylinders, modifying pipework, or altering gas supplies, you must obtain a comprehensive on-site survey conducted by a licensed, certified professional:

• Gas Work (United Kingdom): In Great Britain and the Isle of Man, all gas work is legally restricted under the Gas Safety (Installation and Use) Regulations 1998 to operatives registered with the Gas Safe Register. Nothing on this website authorizes DIY gas work, meter modifications, or unlicensed appliance commissioning.
• Oil & Solid Fuel Installations: Oil boiler installations must be designed and certified by an accredited technician (such as OFTEC in the UK and Ireland). Solid fuel appliances must meet HETAS or equivalent statutory building control approvals.
• Electrical Connections: High-amperage electric boiler installations require dedicated circuit design under BS 7671 (IET Wiring Regulations), compliance with Part P of the Building Regulations, and mandatory pre-notification to your local Distribution Network Operator (DNO).
• Pressure & Commercial Systems: Commercial steam boilers and high-pressure sealed systems operate under high pressure and are subject to the Pressure Systems Safety Regulations 2000 (PSSR) or ASME Boiler and Pressure Vessel Code (BPVC), requiring certified written schemes of examination.

3. Calculation Accuracy, Standards & Inherent Limitations

Our calculation engines implement published methodologies including BS EN 12831-1, CIBSE Guide A/B/C, ACCA Manual J, BS 6891, and BS 5449 fabric heat-loss principles.

Because our tools run client-side without physical property inspection, outputs depend entirely upon the data you input — including floor area, ceiling heights, glazing type, insulation standards, regional design temperatures, simultaneous hot water demand, and system operating pressure. Small input discrepancies compound across whole-house thermal models. All results should be treated as an initial baseline range rather than an immutable design specification.

4. Commercial Independence & Trademark Disclaimers

BoilerSizeCalculator.com operates as an independent technical reference resource:

• We maintain zero commercial affiliations, exclusive distributor agreements, or sponsorship contracts with boiler manufacturers (including Worcester Bosch, Vaillant, Baxi, Viessmann, Ideal, Grant, Weil-McLain, or Slant/Fin).
• All product names, trademarks, logos, and brands referenced on this site belong to their respective owners. Brand names and model specifications are cited strictly for identification, consumer comparison, and nominative fair-use purposes.

5. Disclaimer of Warranties

This website, its calculation tools, and all associated content are provided on an "as is" and "as available" basis, without warranties of any kind, whether express, statutory, or implied, including but not limited to implied warranties of merchantability, fitness for a particular purpose, non-infringement, or mathematical precision for any specific building archetype.

6. Limitation of Liability

To the maximum extent permitted by applicable law, BoilerSizeCalculator.com, its contributors, editors, and hosting operators accept zero liability for any direct, indirect, incidental, consequential, special, or punitive damages — including but not limited to costs of oversized or undersized appliance purchases, unnecessary installation rework, increased fuel expenses, property damage, heating system freezing, or loss of comfort — arising out of or in connection with reliance upon the calculations, tables, or information published here.

Nothing in these terms excludes liability that cannot lawfully be excluded under the laws of England and Wales, including liability for death or personal injury caused by proven negligence.

7. Acceptable Use & Intellectual Property

You may access and utilize this website for personal, educational, and professional planning purposes. You agree not to:

• Engage in automated bulk data scraping, rate-limit bypassing, or unauthorized mirror republishing of our technical datasets.
• Reverse-engineer or package our client-side calculation code into a paid commercial application without attribution.
• Misrepresent outputs generated by this tool as an official, certified engineering survey issued under personal professional indemnity insurance.

Third-party web publishers are permitted to embed our calculation widgets provided the canonical attribution link to BoilerSizeCalculator.com remains intact and functional.

8. Governing Law & Jurisdiction

These Terms of Service are governed by and construed in accordance with the laws of England and Wales. Any disputes arising out of or relating to these terms or your use of the Site shall be subject to the exclusive jurisdiction of the courts of England and Wales.

9. Contact & Questions

Questions regarding these Terms of Service or engineering disclaimers can be directed to our technical team via our Contact Page or by emailing engineer@boilersizecalculator.com. For our data processing policies, please review our Privacy Policy.