What Happens During a Heat Pump Survey: 2026 Guide
Last Updated: October 23, 2026
Quick Summary
A heat pump survey is a two to four hour on-site assessment covering a room-by-room heat loss calculation, existing radiators and pipework, the plant room and loft, and outdoor unit siting. The surveyor uses these measurements to design a correctly sized system and produce a fixed quote.
The survey follows a fixed sequence: consultation, room-by-room heat loss assessment, plant room and loft checks, then outdoor unit siting.
Most homes need some radiator upgrades, though not necessarily a full replacement.
Ask for your heat loss figure in kW and the MCS certification number for grant eligibility.
Clear access to every room, the loft and the plant room is all the preparation you need.
After the survey you receive a heat loss calculation, radiator schedule and fixed price before the grant application.
Table of Contents
Why a Heat Pump Survey Comes Before Any Quote
What Happens During a Heat Pump Survey: Stage by Stage
The Room-by-Room Heat Loss Assessment
Plant Room, Loft and Outdoor Unit Checks
Your Heat Pump Survey Checklist: What the Surveyor Will Look For
Heat Pump Survey Questions to Ask on the Day
How Long Does a Heat Pump Survey Take?
What Happens After a Heat Pump Survey
Frequently Asked Questions
Why a Heat Pump Survey Comes Before Any Quote
A heat pump survey is a detailed on-site assessment of your home's heat loss, existing radiators, pipework and outdoor space, carried out before any installer can give you an accurate quote. Without it, any figure you're given is a guess dressed up as a price.
That's the part most homeowners get wrong. They ring three installers, collect three quotes, and assume the cheapest one is the best value. In reality, a quote produced without a survey tells you almost nothing about what your home actually needs.
At Heatgeek Wales, every design starts with a full room-by-room heat loss assessment. We don't price a job from a floor plan and a rough guess.
Here's what the survey actually involves, stage by stage, so you know exactly what to expect on the day.
What Happens During a Heat Pump Survey: Stage by Stage
A heat pump survey usually takes two to four hours and follows a fixed sequence: a conversation about your home and habits, a room-by-room heat loss assessment, then checks on the plant room, loft and outdoor unit position. Each stage feeds the next.
The surveyor isn't there to sell you anything. They're collecting the measurements needed to size a system correctly.
The Room-by-Room Heat Loss Assessment
This is the core of the visit. The surveyor measures every room's dimensions, window sizes and glazing type, wall construction and insulation levels.
Older properties with solid walls need particular attention. That's not a reason to walk away from a heat pump, but it does change the design.
Radiator output gets checked room by room too. Most homes need some radiator upgrades, though not necessarily a full replacement. We've covered the detail in our guide to whether you really need new radiators for a heat pump.
Watch Out A surveyor who quotes from a desktop assessment without visiting has no way of knowing your radiator sizes or pipework condition. That's how systems end up undersized and homeowners end up disappointed.
Plant Room, Loft and Outdoor Unit Checks
Next comes the practical side. The surveyor checks where the indoor unit and hot water cylinder will sit, and whether there's room.
Loft insulation depth, pipework routes and electrical supply get assessed at the same time. Outside, they'll look at candidate positions for the outdoor unit: clearance from walls, noise distance from neighbours, and ground conditions.
Planning rules matter here. Most air source installations fall under permitted development, but flats and listed buildings often need consent. Your surveyor should flag this early.
Your Heat Pump Survey Checklist: What the Surveyor Will Look For
Here's the heat pump survey checklist a thorough assessment covers. Use it to compare what different installers actually inspect.
Room dimensions and ceiling heights, every room
Window and door sizes, glazing type and draught-proofing
Wall construction: cavity, solid, or timber frame
Loft and floor insulation depth
Existing radiator sizes and output ratings
Pipework diameter and condition
Hot water cylinder location and size
Electrical consumer unit capacity
Outdoor unit position, clearances and noise
Insulation upgrades needed before installation
If an installer skips half of this list, their design is built on assumptions.
Heat Pump Survey Questions to Ask on the Day
Ask these questions while the surveyor is still in your home, not after they've left.
What heat loss figure have you calculated for my home? A proper design produces a figure in kW.
Which radiators need upgrading, and which can stay? Get specifics, room by room.
How did you size the outdoor unit? It should match the calculated heat loss, not your old boiler's rating.
What's your MCS certification number? You need this for grant eligibility.
What flow temperature are you designing for? Lower flow temperatures mean better efficiency.
What happens if the system underperforms? Ask about monitoring and aftercare.
Can I speak to a recent customer with a similar property?
That last one matters more than any brochure. For a wider view of vetting installers, see our guide to choosing between heat pump installers.
Pro Tip Ask the surveyor to show you the heat loss calculation on screen before they leave. A design built on real measurements can be explained in plain terms, room by room. Vague answers are a warning sign.
How Long Does a Heat Pump Survey Take?
A typical heat pump survey takes between two and four hours for an average home. Larger properties, or those needing extensive pipework checks, can run longer.
Here's roughly how the time breaks down:
Stage | Typical Duration | What's Happening |
Initial consultation | 20-30 minutes | Your home, habits and goals |
Room-by-room assessment | 60-90 minutes | Measurements, radiators, heat loss |
Plant room and loft | 30-45 minutes | Cylinder, pipework, insulation |
Outdoor unit siting | 20-30 minutes | Position, clearances, noise |
Design discussion | 20-30 minutes | Findings and next steps |
You don't need to prepare much. Clear access to every room, the loft, and the boiler or plant room is enough. Have any recent energy bills or EPC to hand if you can.
Key Takeaway The survey is the cheapest part of the whole project and the one that determines everything after it. Skipping it to save time is a false economy.
What Happens After a Heat Pump Survey
Once the survey is complete, the installer produces a full system design and a fixed quote based on actual measurements. That's the sequence: survey, design, quote, then grant application.
Expect to receive:
A room-by-room heat loss calculation
A radiator schedule showing what stays and what changes
The proposed outdoor and indoor unit positions
A fixed price for the full installation
From there, the Boiler Upgrade Scheme application is submitted by the installer on your behalf (Boiler Upgrade Scheme (BUS) - Property owners). Our guide to claiming the Boiler Upgrade Scheme grant walks through that process. If you want to see how survey findings turn into a final figure, read our breakdown of heat pump installation cost for a four-bedroom house.
For the installation itself, our step-by-step timeline shows what happens week by week.
Frequently Asked Questions
Is a heat pump survey free?
Many installers charge for a heat pump survey, with fees around £250 being common. However, if you contact Heatgeek Wales directly, they will carry out the survey for free, saving you £250. Always confirm the cost before booking, as some companies deduct the survey fee from your installation quote if you proceed. A free survey still includes the full room-by-room heat loss assessment and system design, so you get the same level of detail without the upfront cost.
Do I need to prepare my home for a heat pump survey?
You do not need to do anything major, but a few small steps help. Clear access to your boiler, hot water cylinder, loft hatch and radiators so the surveyor can measure and photograph them. Have your EPC, recent energy bills and any boiler service records to hand. If you have a loft conversion or extension, mention it, as this affects the heat loss calculation. Also note down any questions you want to ask, using a heat pump survey checklist to make sure nothing is missed.
Will the installer check my radiators during the survey?
Yes, radiator checks are a core part of the survey. The surveyor measures every radiator's dimensions and notes its type and location, then compares this against the room-by-room heat loss figures. Many properties need larger radiators or additional units to run efficiently at lower flow temperatures. The survey report will list which radiators can stay, which need upgrading and any that should be moved, so you have a clear picture before installation begins.
What happens after a heat pump survey?
After the survey, you receive a detailed report and a fixed quotation. The report includes the calculated heat loss for your home, the recommended heat pump size, a radiator schedule and the proposed location for the outdoor unit. If you accept the quote, the installer books the installation date and may help you apply for the Boiler Upgrade Scheme grant. Heatgeek Wales also sets up remote monitoring after commissioning, so system performance is checked and optimised continuously.
The gap between a heat pump that performs and one that disappoints usually comes down to the quality of the survey behind it. If you'd like that survey carried out properly, contact Heatgeek Wales directly and we'll do it free of charge, saving you £250. Our MCS-certified engineers build every design from real measurements, install Vaillant aroTHERM systems, and monitor performance remotely around the clock. Get started with Heatgeek Wales and a design built on your home's actual numbers.
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