What an online quote can't tell you
An EPC is a rating for a building. It is not a measurement of your rooms.
It doesn't know which wall the wind hits. It doesn't know that the back bedroom was an extension. It doesn't know the state of the insulation you can't see. Which is exactly where the sizing goes wrong.
The gap between a heat pump you forget about and one you resent is the survey.
"The heat pump is set and forget… haven't touched or adjusted it for 2 years."
"Just bought a house with an ashp… the house is warmish if the ashp is set to 15 but not toasty warm. It does however use £12 of electricity a day!"
Two heat pumps. Same technology. One of them was sized to the house.
One homeowner's heat pump uses £12 of electricity a day. Another hasn't touched theirs in two years.
Same technology. The difference was decided before anyone ordered the kit.
Nobody sets out to be the first one. And nobody can tell, from a certificate or a phone call, which one they're about to become. That's what the survey settles, for your address, specifically.
You're not stuck because you don't want it. You're stuck because you can't tell a good install from a bad one.
You've read the threads, the ones where it worked and the ones where it didn't, written by people who sound equally sure.
"I'm anxious about choosing the wrong system." · "I'm terrified of choosing wrong." · "I'd be worried about getting the wrong people in for the right job."
That's not indecision. It's a reasonable response to a market where the person quoting knows more than you do, and the money doesn't come back.
The market's own verdict on cheap quotes
There's a line about installers that gets repeated on every forum this subject touches. Put politely: a cheap quote, from whoever will cut the most corners, is a recipe for disaster. We won't argue with it, it's the most useful sentence in this whole subject.
A badly specified heat pump doesn't always announce itself. Some fail outright. The quieter version is worse: it heats the house to warmish and runs hard doing it, and you find that out in January, by which time the kit is already on the wall.
What another year of doing nothing actually costs
The old system still works. That's the honest reason nothing has happened yet. Sensible people run things until they stop, nobody replaces a working boiler for fun. But "nothing" is not free, and you're already paying for it in instalments:
"We lived in a fridge during winter because we couldn't justify spending £500+ a month to keep the place warm."
"Stuck with a fire in the living room to take the edge off the cold, in combination with electric heaters, for years."
The thing that changes the calculation isn't a sales argument. It's the moment the old system ends, it fails, or you move, or someone finally says out loud that it's finished. If you're mid-purchase, that moment is exchange; after it, the heating in that house is your problem. Knowing what it costs is worth doing before then, not after.
The Cold Spot Map
The old way of sizing a heat pump, and what we do instead.
The old way. Someone looks at your EPC, or the size of your current boiler, or the house from the pavement, and prices a heat pump off that. Quick. Cheap to produce. It's why the quotes vary so wildly, and why some are wrong before a spanner comes out.
The Cold Spot Map. An engineer comes to the house and works room by room. Where the heat leaves. Where the insulation isn't what the certificate says. Which rooms run cold and why. Every room, recorded, on one map of your house. The heat pump is then sized from that map, and you get a written build spec off the back of it.
We measure the heat loss room by room, then size the kit to the map.
Backed by the Heat Geek performance guarantee: if the finished system doesn't meet the efficiency it was designed to, it gets put right at no cost to you for two years. Our own workmanship is guaranteed for two years, on top of the manufacturer's warranty.
What you get for the survey fee
- An engineer at the house, working room by room: the sizing comes from measurements of your rooms, not a rating on a certificate.
- The Cold Spot Map for your property: where the heat goes, room by room, so you can see for yourself why the recommended size is the size it is.
- A written build spec: the kit, the sizing, and what needs doing to the house to make it work. Something in writing to hold anyone to, including us.
- A price for the work, given to you in person on the day: the engineer who measured the house is the one who prices it, so you can ask "why that number" while they're still standing there.
The part we'd rather not have to tell you
The survey is paid for, and the fee does not come off the installation. Not "free with no obligation," not credited later, not refunded if you go ahead. You pay for the engineer's time and the map, and if you never speak to us again, we've still been paid for the work we did. We'd rather say that on this page than at your kitchen table.
And we won't be the cheapest quote you get. If the lowest number is the only thing that matters to you, this market's own advice above tells you what usually happens next. But it's your money and your call. We confirm the fee for your property on a quick call before you book anything, it depends on the size of the house, so we won't pretend there's one number.
Don't take our word for it. Don't take our reviews either.
This market's position on reviews is already settled, so here's what to check instead of star ratings. This is the list the market gives itself:
"Make sure you get a reputable company, who are part of the RECC and MCS, and check reviews on the companies."
- Your installation is MCS certified through the Heat Geek platform, which is what makes it eligible for the grant.
- Heat Geek verified, listed on the Heat Geek installer register, which vets and monitors every engineer on it.
- Heatpumps Specialists Ltd, company number 15547644, registered at 32 Wickham Road, Grays, Essex, RM16 4TU. All checkable on Companies House.
- £5 million public liability cover and £250,000 professional indemnity, insured with Jensten Underwriting.
Straight Answers
The things you're actually wondering
The questions this market asks, answered plainly, without pretending heat pumps work everywhere.
If you're not sure, don't book
This isn't for everyone. Don't book if you're renting or the property isn't yours to change; if you want the cheapest number available and nothing else matters; if you're outside Essex, Kent, Hertfordshire, London or Middlesex; or if you need somebody there this week, our current survey lead time is usually two to four weeks.
What happens if you book
You book a call, and we confirm the fee for your property before you pay a penny. If you're happy, we arrange the survey. An engineer comes out, maps the heat loss room by room, and you finish the visit knowing the size, the spec and the price for your house.
P.S. Every quote you get is a number somebody worked out somehow. The only question worth asking is from what. Ours comes from a room-by-room map of your house, made by the person who then prices the job in front of you. If a cheaper quote came from a look at the front of the house and a glance at your EPC, you're not comparing two prices. You're comparing a measurement and a guess.
The people who do the work
Jamie measures it, sizes it, and installs it, not a subcontractor.
The engineer who maps your heat loss is the one who prices the job and fits the system. One person accountable from the first measurement to the last radiator, and the one you ring afterwards.
Book a Call
Book a call about your heat loss survey.
A quick call with an engineer, we confirm the fee for your property, answer anything you want to ask, and book the survey only if you're happy to. No obligation.