Where Is Your Home Losing Heat?
Choose your property type and current insulation state below — we'll show you a breakdown of where heat is escaping and which measures fix each problem.
What to do about it
Get a free energy survey
EcoHome UK surveyor visits are completely free. We'll identify every heat-loss point and check whether you qualify for ECO4 or GBIS grant funding.
Book a free survey →Methodology & sources
Heat-loss percentage splits are based on guidance published by the Energy Saving Trust for a typical uninsulated UK home. The EST estimates that in a typical home: walls account for ~35% of heat loss, roof/loft ~25%, draughts and ventilation ~15%, floor ~10%, windows ~10%, and doors ~5%.
| Zone | Typical loss (uninsulated) | Fix | Reduction from fix |
|---|---|---|---|
| Walls | 35% | CWI / IWI / EWI | ~70% of zone |
| Roof/loft | 25% | Loft insulation | ~75% of zone (full), ~30% (partial top-up) |
| Draughts & ventilation | 15% | Draught-proofing | ~60% of zone |
| Floor | 10% | Floor insulation | — |
| Windows | 10% | Double / triple glazing | ~50% of zone |
| Doors | 5% | Door seals / replacement | — |
How adjustments work: When a user indicates an element is already insulated/sealed, that zone's heat loss is reduced by the percentage shown above, and the remaining heat-loss values are re-scaled so the total still adds to 100%. This shows where heat is currently being lost, not where it was lost before insulation.
Property type: The baseline split is the same across property types (it reflects physics, not floor area). Property type informs the qualitative advice and which insulation measures are most impactful.
Sources: Energy Saving Trust — Home Insulation · Energy Saving Trust — Draught-proofing · Energy Saving Trust — Double glazing
Percentages are illustrative and typical — actual heat loss varies by property age, construction, orientation, occupancy and local climate. This tool is for guidance only; a professional survey will give a precise picture.