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Heat loss

Heat Loss Calculations for Air Source Heat Pumps (UK)

Produced to the scope agreed at booking, using inputs captured from the site pack.

We document inputs and assumptions so installers and homeowners can understand the basis of the result.

Pricing is POA and depends on scope. We confirm scope, timeline, and pricing before you book—nothing happens until you approve.

Survey professional using measurement tools during a site assessment

Measured inputs, documented assumptions

Heat loss outputs are only as useful as the inputs. We document what was measured and what was assumed—so the basis of the result is easy to understand.

What you can expect

We keep it evidence-led and explicit about what was used as an input.

Inputs

Inputs captured from the site pack

  • Measurements relevant to the booked scope
  • Notes and photos to support key assumptions
  • Room-by-room context where applicable
Assumptions

Assumptions documented

  • Assumptions shown clearly in the pack
  • Constraints made visible
  • Designed to reduce follow-up questions
Handoff

Installer-ready structure

  • Consistent layout
  • Evidence placed next to decisions
  • Built for design → install → sign-off workflows

Calculations you can stand behind

Truth-safe outputs: scope agreed at booking, inputs documented, assumptions visible.

Structure

Standardised, room-by-room outputs

  • Room-by-room context where applicable
  • Consistent presentation for installer handoff
  • Designed to reduce follow-up questions
Assumptions

Inputs and assumptions made visible

  • Inputs captured from the site pack
  • Constraints and uncertainties documented
  • So results are explainable to the homeowner
Integrations

Less re-typing

  • Integration options with heat loss software
  • Consistent field structure for reliable inputs
  • Built for installer workflows

Frequently asked questions

A heat loss calculation determines how much heat a property loses, which is essential for correctly sizing a heat pump system. It considers factors like room dimensions, insulation levels, window types, building age, and property characteristics to calculate the heating demand.

A heat loss calculation is essential for correctly sizing a heat pump system. Undersized systems won't heat the property adequately, while oversized systems are inefficient and costly. The calculation ensures the heat pump is matched to the property's actual heating requirements.

Heat loss calculation costs vary depending on property size and complexity. We confirm scope, timeline, and pricing before booking—nothing happens until you approve. Contact us for a quote.

The site visit for measurements typically takes 1-2 hours. Heat loss calculations are delivered the next day if required, with all assumptions and site inputs documented clearly.

Heat loss calculations are produced to industry standards including MIS3005-D and CIBSE guidelines. The calculation includes assumptions and site inputs documented clearly for installer use.

A heat loss calculation requires room-by-room measurements, insulation levels, window types, building age, property characteristics, and heating system details. We capture this information during the site visit and document all assumptions clearly.

Related guides for heat loss work

How inputs are captured, what assumptions matter, and where thermal imaging fits.

Heat Loss Calculations Across the UK

Based in Doncaster, we provide heat loss calculations across England, Scotland, and Wales. Select your area below:

Related Services

Heat loss calculations are often part of a complete heat pump survey. We also provide standalone calculations and related services.