Features

Comprehensive calculations, simple to use

A room-by-room heat loss engine following the CIBSE Domestic Heating Design Guide and an AI assistant do the heavy lifting — you review and decide.

Live room-by-room heat loss

Build a room-by-room heat loss model using property geometry, fabric performance and local design temperatures. Every edit recalculates the room load immediately, keeping the whole-home result traceable.

What it delivers

  • CIBSE DHDG method (BS EN 12831-1)
  • Live fabric and ventilation losses
  • Room-level calculation evidence

Building Heat Loss

CIBSE DHDG · live calc

7.54kW

total

Sitting Room1.54 kW
Kitchen / Dining Room1.17 kW
Principal Bedroom1.00 kW
Dining Room / Bedroom 50.77 kW

Fabric + ventilation losses per room, recalculated live.

Example home from our demo. Modelled estimates, not a quote or a guarantee.

AI EPC and document parsing

Bring EPCs, plans and supporting documents into one reviewable evidence trail. HeatLens extracts likely values, shows where they came from and leaves the assessor in control of every accepted update.

What it delivers

  • Source-linked field proposals
  • Confidence and page references
  • Accept or reject before applying

EPC Certificate.pdf

Floor areaProposed
Wall typeProposed
Build yearProposed
Accept or reject each value · evidence linked

Emitter suitability at low flow

Check every existing radiator at the proposed low flow temperature. Outputs are adjusted against each room’s design load so undersized emitters are visible before specification or installation.

What it delivers

  • Live output at target flow temperature
  • Pass, marginal and undersized flags
  • Room-by-room replacement evidence

Emitter Suitability

Demo home at its 45°C design flow

Sitting Room

K1 · 600×1000 + K1 · 600×1200

46%

Undersized

Kitchen / Dining Room

P+ · 600×1000

45%

Undersized

Principal Bedroom

K1 · 600×1200

46%

Undersized

HeatLens flags the rooms the existing radiators can't heat before you quote.

Example home from our demo. Modelled estimates, not a quote or a guarantee.

Auto-generated retrofit scenarios

Compare practical retrofit pathways against the current property. Fabric upgrades, airtightness and heat-pump assumptions flow through to heat loss, system size, energy use and estimated running cost.

What it delivers

  • Editable retrofit assumptions
  • Running-cost comparison
  • Whole-home impact shown side by side

Retrofit Comparison

Current home

Fabric first

Deep retrofit

Each scenario recalculates heat loss, system size and running cost against the current home.

Heat pump and tariff modelling

Model heat-pump running costs against flat and time-of-use electricity tariffs. Monthly demand shows when energy is used, not just the annual total.

What it delivers

  • Monthly weather-adjusted performance
  • Day and off-peak consumption splits
  • Tariff source and review tracking

Annual Running Cost

Flat
Time-of-use

Modelled running cost compared across tariffs, from your own project data.

Results and professional reports

Turn the completed assessment into a clear technical result and professional project evidence. Key assumptions, room loads, system sizing and cost outcomes remain connected to the underlying calculation.

What it delivers

  • Calculation summaries and project evidence
  • Client and installer report views
  • Versioned, reviewable project evidence

Heat Loss Report

Client report
Building summary
Room-by-room loads
Heat pump sizing
Emitter schedule
Tariff & running cost

7.54

kW heat loss

9.0

kW heat pump

Example home from our demo. Modelled estimates, not a quote or a guarantee.

Ember, your assistant in every project

Ember is the assistant inside HeatLens. Open it on any screen and ask about the job in your own words: it reads that project's rooms, emitters, scenarios, tariffs, documents and live heat loss result, so the answer is about this house. Tell it details such as the survey date or main fuse and it proposes the exact changes for you to approve. Attach a quote, EPC or bill and it reads the file and answers from it. Installers get short technical answers; homeowners get plain ones. Prefer to talk it through? Request a callback.

What it delivers

  • Answers from your own project data
  • Fills in job details only after you approve
  • Supports your design, not a certified design

Ember

Will the kitchen / dining room radiator keep up at 45°C flow?
At 45°C flow the P+ gives about 523 W against a 1,171 W room load, so it is undersized by 648 W. A P+ 600×2400 (about 1,254 W) would cover it.
Prefer to talk it through? Free callback

Example home from our demo. Modelled estimates, not a quote or a guarantee.

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