An independent sizing study and grant navigation service for air-source and ground-source heat pumps — sized correctly for your property, optimised for the highest available MaPrimeRénov' grant, and specified independently before you approach any installer.
The most common heat pump failure in French rural properties is not the equipment — it is the sizing. An oversized unit short-cycles, degrades efficiency, and wears out faster. An undersized unit runs continuously at peak load and cannot maintain comfort on the coldest days. In old stone properties with mixed insulation, neither problem is immediately obvious until the first full winter.
A proper heat load study uses EN 12831 methodology to calculate exactly how many kilowatts your building loses per degree of temperature differential — room by room, wall by wall. That figure determines the output capacity required. From there, flow temperature analysis tells you whether your existing radiators or underfloor circuits can work with a heat pump at all, or whether they need upgrading first. Getting that wrong before you buy is expensive. Getting it right before you commit costs a fraction of the consequence.
This assessment is also the prerequisite document for a valid MaPrimeRénov' application. Submitting without a compliant heat load study is one of the most common reasons dossiers are rejected or queried.
Dordogne stone properties have high thermal mass and highly variable wall U-values. Standard online calculators built around modern construction significantly underestimate heat demand. A room-by-room study with actual wall construction is the only reliable basis for sizing in these buildings.
Heat pump replacement of an oil or gas boiler qualifies for MaPrimeRénov' par geste in 2026. Grant values range from €3,000 to €5,000+ depending on income band, with top-up CEE credits available. A compliant heat load study is required documentation for every application.
Air-source units are cheaper to install and maintain but less efficient in very cold conditions. Ground-source delivers higher SCOP but carries significant groundworks cost. This assessment helps you understand which is appropriate for your property before any supplier engagement.
A written specification document that belongs to you — not to any installer. You can take it to any RGE-certified heat pump contractor for a like-for-like tender.
Free 30-minute conversation to confirm scope and suitability
Floor plans, wall construction, existing heating circuit details, DPE if available
Room-by-room EN 12831 calculation using PAC'Réno methodology and DJU climate data
Type, output capacity, flow temperature assessment, grant eligibility confirmation
Written specification with installer briefing document — typically within 7 working days
The most common mistake is approaching a heat pump installer without knowing what size of system your property actually needs. Here's how to sequence this correctly.
It can — but it depends heavily on the flow temperature your radiator or underfloor circuit requires. Heat pumps are most efficient when running at low flow temperatures (35–45°C). Old stone properties with large original radiators often work well precisely because those radiators were oversized for a boiler — they can deliver adequate heat at lower temperatures. But undersized radiators, or properties that have had radiators removed, may need upgrading. This is one of the core questions the assessment answers before any money is committed.
An air-source heat pump (ASHP) extracts heat from outdoor air. It is simpler to install, lower capital cost, and works well in the Dordogne H1c climate where winter temperatures rarely drop below −5°C for extended periods. A ground-source heat pump (GSHP) extracts heat from the ground via buried loops — it is more efficient in cold conditions but requires significant groundworks and higher upfront cost. For most rural properties in the Dordogne, ASHP is the practical and economically sound choice. The assessment will give you a clear rationale either way.
MaPrimeRénov' 2026 covers heat pump installation replacing a fossil-fuel boiler (oil, gas, or LPG). Grant amounts vary by income band: intermédiaires and supérieurs receive €3,000–€4,000; modestes receive up to €5,000; très modestes can receive significantly more. CEE (Certificats d'Économies d'Énergie) top-up credits are also available and can add a further €1,000–€2,500 depending on the installer's CEE programme. The assessment includes a grant estimate based on your household income band and confirms the documentation requirements. Use the grant eligibility checker for a preliminary indication before booking.
Yes. MaPrimeRénov' requires that installation work is carried out by an RGE (Reconnu Garant de l'Environnement) certified contractor — specifically QualiPAC or equivalent qualification for heat pump installation. This is not optional. The assessment provides a vendor-neutral installer briefing that any RGE contractor can price against — it is not tied to any specific supplier or installer.
The core inputs are: approximate floor area by room (or a floor plan), wall and roof construction type, window areas and glazing specification if known, existing heating system (boiler type, radiator sizing where available), and a recent electricity or fuel bill if possible. A DPE (Diagnostic de Performance Énergétique) is useful but not mandatory. Everything can be gathered during the initial conversation — you don't need to prepare a technical dossier before calling.
Yes — and in many cases this makes strong sense. An MVHR system reduces the heat load by recovering warmth from extracted air, which can reduce the required heat pump output capacity. A combined MVHR and heat pump study costs less than two separate studies and ensures the two systems are sized consistently. If you're also considering solar and storage, the Home Energy Autonomy Assessment covers all of these technology pathways in a single whole-home review — which is usually the most efficient starting point for properties undergoing significant renovation.
The initial conversation is free and without commitment. If this service is right for your situation, a fixed fee is agreed before work begins.