Answer first
Expect room measurements and construction assumptions for heat loss, a radiator or underfloor-heating record, hot-water demand, possible cylinder and outdoor-unit positions, pipe and cable routes, electrical-supply checks, drainage, sound and planning questions.
The survey should lead to an understandable proposal: calculated heat demand, selected equipment, emitter and cylinder changes, controls, installation scope, assumptions and exclusions. If important facts remain unknown, they should be stated rather than guessed.
Heat pumps installed in the government-funded demonstration project
View sourceHomes in that project needing at least one radiator replaced
View sourceHomes needing a new thermal store such as a hot-water tank
View sourceRequest a £0 home survey and written heat-pump quote
Share your property, current heating and priorities. FLO can arrange the checks needed to turn general heat-pump advice into a complete written proposal.
Before the visit: give the surveyor useful context
Share the postcode, property type, approximate age, extensions, present fuel, household size and why you are considering a heat pump. Mention cold rooms, limited hot water, renovation plans, a failing boiler or an existing quote you want to compare.
Have recent energy use available if practical. Historic bills do not replace a heat-loss calculation, but they help test whether its annual result is plausible. Tell the surveyor about fires, plug-in heaters or rooms normally left unheated.
- Twelve months of fuel or electricity use
- EPC, plans or renovation drawings if available
- Boiler, cylinder and consumer-unit access
- Any known planning, title or neighbour constraint
- Your comfort, hot-water and timing priorities
The building survey supports room-by-room heat loss
The surveyor records dimensions, exposed surfaces, windows, doors and the construction of walls, floors and roofs. Insulation must be evidenced or treated cautiously; appearance alone does not prove what is inside a wall or loft.
Each room has an intended temperature and design heat loss. This is how the designer avoids hiding a cold extension or exposed corner bedroom inside one whole-house total.
The heating system is recorded, not assumed
Radiator type and size, underfloor zones, pipework, pumps, valves and controls affect the water temperature and flow the new system can use. The survey should identify what can remain and where more emitter output or pipework investigation is needed.
The 742-home Electrification of Heat project found that 93% of installed homes needed at least one radiator replacement. That does not mean every radiator in every home must change. It shows why room-by-room checking is normal design work.
Hot water and equipment space can change the answer
The surveyor asks how many people use hot water, the number of baths and showers, simultaneous use and recovery expectations. Existing cylinders need their coil, insulation, condition and size checked—not just their external dimensions.
In the same demonstration project, 81% of homes needed a new thermal store because they previously had a combi boiler or the old cylinder coil was unsuitable. A small number of flats used heat batteries where a tank would not fit. These are design choices, not a universal rule.
Outdoor position, electricity and installability finish the picture
A candidate outdoor position needs free airflow, access, drainage and a route for pipes and cables. Sound, planning, listed-building, conservation-area, ownership and neighbour issues may need more detailed checks.
The electrical survey records the supply, main fuse, consumer unit, earthing and other large loads such as an EV charger. The installer then follows the network-operator process and identifies upgrades or approvals before they can delay the job.
What you should receive after the survey
A responsible survey should not disappear into an unexplained total. The proposal should make the system, changes and design basis clear enough to discuss before work starts.
Ask how revised findings are controlled. If a hidden pipe route, asbestos concern or planning condition appears later, the impact on price and design should be agreed in writing.
- 1
Heat demand
Room-by-room losses, design temperatures and the overall sizing basis.
- 2
Whole-system specification
Heat pump, cylinder, emitters, controls, electrical work and retained components.
- 3
Installation scope
Routes, positions, access, removals, making good, commissioning and waste.
- 4
Commercial terms
Price, assumptions, exclusions, payment stages, warranty and aftercare.
What to read next
Related answers and services
Questions people also ask
How long should a heat-pump survey take?+
There is no useful universal duration. A complex or larger home takes longer. Judge the coverage and outputs rather than accepting a speed target.
Can the survey be done remotely?+
Photos and calls can support an early conversation, but final design and price commonly need property measurements, equipment checks and installable routes verified on site.
Do I have to clear every room?+
Provide reasonable access to radiators, windows, loft hatches, the present heating equipment, consumer unit and likely routes. Ask the surveyor in advance if anything specific is required.
Evidence used for this answer
Figures are explained in context and links go to the independent source. Prices, tariffs, scheme rules and standards can change, so check the source again before making a financial or technical decision.
- Energy Systems Catapult: home surveys and installation reportEvidence from 742 installations, including radiators, cylinders, survey constraints and typical installation duration.
- MCS heat-pump design standardTechnical requirements for heat loss, equipment selection, domestic hot water and system design.
- MCS domestic heat-pump guideConsumer guidance covering design, installation, controls, handover and maintenance.
- Energy Networks Association: connecting heat pumpsThe national low-carbon-technology notification and network assessment process for domestic installations.