Getting the size right matters. An undersized heat pump struggles in cold weather, while an oversized one costs more to buy and can switch on and off frequently, which wastes energy and wears components. Sizing from a rule of thumb, or simply matching the old boiler's output, is a common cause of poorly performing systems. A measured, room-by-room design avoids both problems and shows the reasoning behind every figure.
A surveyor visits your home to measure each room, window and wall before any heat pump is sized. For Mid Glamorgan homes with extensions or loft conversions, each part of the house is assessed on its own construction. The survey in Mid Glamorgan includes a check of where the outdoor unit could sit and how its sound would reach neighbours.
Who it suits
- Anyone getting a heat pump quote, as the first step
- Homeowners planning insulation or building work who want to know the effect on heat demand
- Landlords comparing properties before deciding where to switch first
- Homes with an existing heat pump that seems undersized or expensive to run
Grants and rules for heat pumps in Wales
Homes in Mid Glamorgan can use the Boiler Upgrade Scheme, which applies in Wales as well as England: £7,500 towards an air source heat pump, or £9,000 when it replaces oil or LPG heating for installations from 21 July 2026 to 31 March 2027. The MCS-certified installer named in your quote applies and deducts the grant.
Installing heat pumps is zero-rated for VAT across the UK until 31 March 2027. Wales has its own permitted development rules for air source heat pumps, so we check what applies to your property, including listed building and conservation-area constraints, at the survey.
Heat loss survey prices in Mid Glamorgan
Here are typical prices for heat loss surveys in Mid Glamorgan, installed and including VAT. Use the guide price tool for a figure based on your home, then a survey confirms it in writing.
| Survey | Guide price |
|---|---|
| Home survey and heat loss calculation with an installation quote | Free |
| Stand-alone heat loss survey and report | £150–£400 |
Inc VAT. A stand-alone report is for homeowners who want the design without an installation quote.
Towns we cover in Mid Glamorgan
We cover 11 towns in Mid Glamorgan for heat loss surveys. Each links to local guide prices and the grant position for Wales.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Bridgend | CF31 | Porthcawl | 7 h 49 min |
| Merthyr Tydfil | CF47 | Aberdare | 7 h 47 min |
| Pontypridd | CF37 | Llantrisant | 7 h 49 min |
| Aberdare | CF44 | Mountain Ash | 7 h 47 min |
| Caerphilly | CF83 | Pontypridd | 7 h 49 min |
| Maesteg | CF34 | Port Talbot | 7 h 48 min |
| Porthcawl | CF36 | Bridgend | 7 h 50 min |
| Bargoed | CF81 | Blackwood | 7 h 48 min |
| Llantrisant | CF72 | Pontypridd | 7 h 49 min |
| Mountain Ash | CF45 | Aberdare | 7 h 48 min |
| Tonypandy | CF40 | Pontypridd | 7 h 48 min |
Heat loss surveys questions
Why can't you size the heat pump from my boiler?
Boilers are often much larger than a home's real heat loss, because they are sized for fast hot water and quick warm-ups. Matching a heat pump to the boiler's output usually means an oversized unit that costs more and switches on and off too often. A room-by-room calculation finds the actual heat demand, which is what the heat pump needs to meet.
Can I use the heat loss report to get other quotes?
Yes. A stand-alone heat loss report is yours to use, including sharing it with other installers so their quotes are based on the same figures. Comparing quotes like for like makes it easier to see differences in equipment, radiator upgrades and workmanship terms. The report states the assumptions used wherever construction could not be confirmed.
How long does a heat loss survey take?
A typical survey takes 1–3 hours on site, depending on the size and complexity of the home. Larger or older houses with mixed construction, extensions or many rooms take longer. The calculations and design are completed afterwards, and the results are included in your quote or stand-alone report.
Will the survey check noise from the outdoor unit?
Yes. The surveyor identifies possible positions for the outdoor unit and carries out the MCS noise assessment, which estimates the sound level at the nearest neighbouring window from the unit's sound power level, distance and any barriers. In England, meeting the MCS planning standards is one of the conditions for permitted development. Wales, Scotland and Northern Ireland have their own rules, which we check.