Why are my heating bills so high?
High heating bills mean one of two things: you are using a lot of energy, or your home is wasting a lot of it — and usually it is the latter. Energy prices are outside your control, but how much heat your home loses is not. If you are paying a great deal and still feeling cold, the money is literally leaking out of the building, through air leakage, poor insulation and thermal bridges. A home energy investigation finds out where, so you can stop paying to heat the outdoors.
The key insight is that not all improvements are equal. Spending on the wrong measure — new windows when the real loss is the floor, or a bigger boiler when the problem is air leakage — wastes money. Measurement tells you which improvements will actually move your bills.
Why an EPC won't cut your bills
An Energy Performance Certificate is a modelled estimate from standard assumptions about your property type. It does not measure your actual building, does not test your airtightness, and locates no real defects. It can suggest generic measures, but it cannot tell you that half your heat is leaking through an unsealed floor or a specific thermal bridge. To cut real bills you need a measured investigation of your real home.
Where your home wastes energy
Energy is wasted through several routes at once, and the balance is different in every home. Uncontrolled air leakage carries warm air straight out; missing or poor insulation lets heat conduct away through walls, roof and floor; thermal bridges create concentrated cold spots; and an unbalanced ventilation strategy can dump warm air outside faster than needed. A home energy investigation measures each so we can rank them.
Planning a heat pump or major upgrade?
A home energy investigation is especially valuable before installing a heat pump or undertaking a major refurbishment. Heat pumps run most efficiently in homes with low, well-understood heat loss. By measuring your losses and air leakage first, we can tell you which fabric improvements to prioritise so a future system is correctly sized and cheap to run — avoiding the costly mistake of an oversized system on an untreated building.
How Retrofit IQ investigates home energy waste
We use a measured, whole-building approach. Thermal imaging maps heat loss and thermal bridges; blower door testing quantifies air leakage; smoke tracing locates it; and we assess insulation, windows, floors and ventilation. The findings are interpreted through building physics and ranked by impact. You receive a clear picture of where your energy — and money — is going, and a prioritised, sequenced plan to cut it.
This is a Building Performance Investigation
A home energy investigation is, in effect, a Building Performance Investigation with the emphasis on running costs. It ties air leakage, insulation, thermal bridging and ventilation into one prioritised, fabric-first plan — the most reliable route to a warmer home and lower bills.
The hidden cost most homeowners miss
When people picture heat loss, they think of walls and windows. Yet in a great many London homes the single largest — and most overlooked — cost is uncontrolled air leakage. Warm air you have paid to heat is continuously replaced by cold air pulled in through gaps, and your heating simply runs harder to keep up. Because it is invisible, it is rarely on anyone's list of improvements, which is exactly why measuring it so often changes the priorities. A blower door test turns this hidden cost into a number you can act on.
This matters for your budget because it reorders what is worth doing. A homeowner who was about to spend heavily on new windows may discover that sealing the floor, loft hatch and service penetrations would deliver more comfort for a fraction of the cost. Measurement is what reveals that, and it is why we never recommend works before we have investigated.
Why comfort and cost improve together
Cutting energy waste is not only about the bill at the end of the month. A home that loses heat quickly feels draughty and cold, with rooms that never quite warm up and heat that vanishes the moment the boiler switches off. The same measures that reduce your running costs — sealing leaks, correcting insulation, addressing thermal bridges — also make the home genuinely more comfortable and more stable in temperature. You are buying comfort and lower bills with the same investment, which is why fabric improvements tend to be so satisfying once the right ones are identified.
A realistic plan and sensible payback
Not every improvement pays back at the same rate, and an honest investigation says so. Some measures — draught sealing, loft top-ups, hatch and downlight sealing — are relatively inexpensive and repay quickly. Others, such as external wall insulation, cost more and are best timed alongside other works like re-rendering or a refurbishment. Our report sequences your improvements by impact and cost, so you can spread the work sensibly over time and always know that the next step is the right one. This avoids the twin traps of doing nothing because it all feels overwhelming, and doing the wrong thing because it was the most obvious.
Common misconceptions about saving energy
A few beliefs cost homeowners dearly. The first is that a bigger boiler or a new heating system will fix a cold, expensive home — when the real answer is to lose less heat first. The second is that an EPC recommendation is a survey — it is a modelled estimate that inspects nothing. The third is that insulation alone is the answer, when air leakage and thermal bridging are frequently the bigger culprits. A home energy investigation replaces all three assumptions with measured facts about your specific building.
What the investigation covers on the day
A home energy investigation is a thorough, hands-on visit rather than a quick walk-round. We carry out thermal imaging throughout the property in valid conditions, set up and run the blower door test to measure your air-leakage rate, and use smoke tracing to locate the leaks the test exposes. We inspect the loft, windows, doors and, where accessible, floors and walls, noting insulation, construction and any defects. Throughout, we explain what we are finding, so by the time we leave you already understand the headline story of how your home is performing.
The written report that follows turns those findings into a ranked, costed plan. It sets out the measures in order of impact and value, so you can see at a glance where to start and how to phase the work over months or years if you prefer. Nothing is recommended that we have not seen a reason for on site.
Reading your bills alongside the fabric
Your energy bills are a valuable clue, and we are happy to consider them alongside the physical findings. Unusually high consumption for the size and type of property, or bills that rise sharply in cold spells, help confirm where the losses are greatest and how much scope there is to improve. Combining what the meter says with what the building shows produces a fuller picture than either alone — the measured fabric explains the bill, and the bill validates the priorities in the plan.
Funding, grants and doing it in stages
Improving a home's efficiency does not have to happen all at once. Because our report sequences measures by impact and cost, you can start with the quick, inexpensive wins and phase the larger works as budget allows, always knowing the next step is the right one. Where grants or funding schemes are relevant to your property, a clear, measured understanding of your home's needs puts you in a far stronger position to use them well — spending support on the measures that genuinely help rather than generic ones.
The long-term value of an efficient home
Beyond the monthly saving, a warmer, more efficient home is more comfortable to live in, healthier, and more resilient to rising and volatile energy prices. As standards and buyer expectations shift towards low-energy homes, a property with a documented, measured improvement history is an increasingly attractive one. A home energy investigation is the foundation of all of this: it replaces guesswork with evidence, so every pound you invest in your home works as hard as it can.
What you receive
- A measured picture of where your home wastes energy
- Thermal images and a measured air-leakage result
- Heat losses ranked by impact on comfort and cost
- A prioritised, sequenced improvement plan — fabric first
- Heat-pump readiness guidance where relevant
A real-world investigation example
A homeowner facing steep energy bills, and paying a lot to feel only just comfortable, wanted to know where to spend to cut costs. Rather than guess, we measured: the blower door revealed a high air-leakage rate — warm air was effectively being reheated and thrown away all winter — while thermal imaging found missing insulation above a bay window and a cold, uninsulated extension roof. The heating system was fine; the fabric was the drain. A prioritised, fabric-first plan tackling the biggest leaks and the worst-insulated areas first was set to reduce the wasted energy far more cost-effectively than the new boiler the owner had been considering.
Common homeowner mistakes
A frequent mistake is chasing lower bills by replacing the boiler or heating controls while ignoring the fabric that is wasting the heat in the first place. Another is making improvements in the wrong order — for example new windows before cheaper, higher-impact air sealing — so the money returns less than it should. Trusting an EPC's generic recommendations, rather than measuring the specific home, sends spending in the wrong direction. And installing renewable heating onto a leaky, poorly insulated home locks in the high running costs the technology was supposed to lower.