ASHP Heat Loss Assessment

I’m refurbishing a residential property that’s a little over 20,000 sq ft and will have comprehensive insulation—walls, roof and floor are all wrapped, so overall fabric heat losses should be modest. Before I lock-in to an air-source heat-pump order, I need a precise heat-loss calculation that tells me the capacity I actually require rather than what a brochure suggests.

Please base the figures on standard UK design temperatures and show every assumption you make (U-values, air-change rates, internal gains, etc.). I’m happy for you to use recognised tools such as Heat Engineer, MCS or similar software, as long as the final numbers can be traced back to accepted methodology.

Deliverables
• Whole-house heat-loss figure (kW at design temperature)
• Room-by-room breakdown so I can size emitters correctly
• Recommended ASHP output range with a brief rationale
• Summary sheet of key assumptions and any improvement notes

I’ll supply floor plans, build-up details and any other data you request as soon as we start. Accuracy is the priority; a clear, well-structured PDF and the raw spreadsheet or software export will be perfect for hand-off to my installer.