For installation enquiries the survey is free, and the results go straight into your written quote. If you want the calculation on its own, for example to plan building work or to compare quotes, a stand-alone heat loss survey and report has a guide price of £150–£400, including VAT.
Houses in County Londonderry built in different eras can need very different heat pump sizes, which is why each is calculated room by room. A surveyor visits your home to measure each room, window and wall before any heat pump is sized. For County Londonderry homes with extensions or loft conversions, each part of the house is assessed on its own construction.
Who it suits
- Self-builders and architects who need emitter and system sizes early
- Homeowners planning insulation or building work who want to know the effect on heat demand
- Homes with an existing heat pump that seems undersized or expensive to run
- Anyone getting a heat pump quote, as the first step
Grants and rules for heat pumps in Northern Ireland
Northern Ireland does not have a dedicated heat pump grant for homeowners at present, and the Boiler Upgrade Scheme does not apply here. Heat pumps have sometimes been funded through the Northern Ireland Sustainable Energy Programme, so it is worth checking what is open when you enquire about a home in County Londonderry.
There is no VAT on installing a heat pump in Northern Ireland until 31 March 2027, the same as in Great Britain. Planning and building control here follow Northern Ireland's own rules, so the survey checks the unit position against them.
Heat loss survey prices in County Londonderry
The ranges below are typical installed prices for homes in County Londonderry, including VAT. A survey sets the exact figure, because two similar-looking houses in County Londonderry can need quite different radiators and pipework.
| Survey | Guide price |
|---|---|
| Home survey and heat loss calculation with an installation quote | Free |
| Stand-alone heat loss survey and report | £150–£390 |
Inc VAT. A stand-alone report is for homeowners who want the design without an installation quote.
Towns we cover in County Londonderry
We cover 7 towns in County Londonderry for heat loss surveys. Each links to local guide prices and the grant position for Northern Ireland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Derry/Londonderry | BT48 | Limavady | 7 h 10 min |
| Coleraine | BT52 | Portstewart | 7 h 08 min |
| Dungiven | BT47 | Limavady | 7 h 11 min |
| Limavady | BT49 | Dungiven | 7 h 09 min |
| Maghera | BT46 | Magherafelt | 7 h 12 min |
| Magherafelt | BT45 | Maghera | 7 h 13 min |
| Portstewart | BT55 | Coleraine | 7 h 08 min |
Heat loss surveys questions
What is a design flow temperature?
The design flow temperature is the temperature of the water sent to your radiators or underfloor heating on the coldest design day. Heat pumps are more efficient at lower flow temperatures, typically around 35–50°C. Choosing it is a balance: a lower figure improves efficiency but can mean larger radiators in some rooms, so the design shows both.
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.
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.
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.