Therightheatpumpstartswiththeright numbers

It depends on your home's heat loss — which is exactly what we calculate. A typical 100 m² (1,000 sq ft) home might need 5–12 kW depending on insulation, windows, climate, and building age. Oversizing is the most expensive mistake — an oversized heat pump costs more to buy, short-cycles, and wears out faster. Our room-by-room calculation gives you the precise number so you can choose with confidence.

Your home's heat loss (in kW or BTU/h) is the single most important number for choosing a heat pump. It tells you exactly how much heating power your home needs on the coldest day. A heat pump rated at or slightly above your total heat loss will keep every room comfortable without wasting energy. That's why a proper heat loss calculation — not a rule-of-thumb or square-footage estimate — is essential before buying.

For heating: EN 12831 (EU) and ASHRAE/Manual J (US) with age-based thermal bridging, room-specific ventilation rates, and reheat capacity. For cooling: ASHRAE CLTD/CLF method accounting for thermal mass, solar orientation, and time-lag effects. These are the same industry-standard methods used by licensed HVAC engineers — your installer will recognize the calculations immediately.

You'll need basic room dimensions (length, width) and to know which walls face outside. Wall thickness, insulation type, and window specs are selected from presets based on your building age — no tape measure needed for those. Most users complete the wizard in under 10 minutes.

Most free calculators use simplified formulas that ignore thermal mass, ventilation rates, solar gains, and building orientation. We perform a full room-by-room analysis using the same engineering standards a professional would use — giving you results you can actually rely on when choosing equipment.

Yes. An oversized heat pump is one of the most common — and expensive — mistakes homeowners make. It costs more to buy, short-cycles (turning on and off too frequently), runs less efficiently, and wears out faster. Our report gives you the exact kW your home needs, so you can pick a heat pump that matches — not one that's 50% bigger than necessary. Most homeowners save far more than the cost of the report.

Absolutely — that's one of the best ways to use it. When you bring a professional heat loss report to the conversation, your installer can recommend the right heat pump based on precise data instead of rough estimates. It makes the process smoother for both sides — you get confidence in the sizing, and your installer can focus on finding the best heat pump for your actual needs.

A detailed professional PDF with: heat loss analysis (total + per-room), cooling load analysis, room-by-room breakdown tables, heat loss intensity comparisons, complete input data documentation, and all calculation parameters. The report scales with your building — more rooms, more detail. Ready to share with your HVAC installer or contractor.

Yes — we offer a 30-day money-back guarantee on all paid services, no questions asked. If you're not satisfied for any reason, contact us and we'll issue a full refund. You can also try our free single-room analysis first to verify the quality before purchasing.

No. Your building data stays in your browser and is never stored on our servers. When you run a calculation, data is sent to our calculation server, processed in memory, and the results are returned — nothing is permanently saved. We never sell or share your data for marketing purposes.