In short: an efficient home needs less energy to stay at a comfortable temperature, so you spend less on heating and cooling and enjoy more comfort all year. Efficiency depends on insulation, windows, building services (such as aerothermal heat pumps) and design. To compare homes, always ask for the energy performance certificate, which is mandatory when selling or renting in Spain.
When searching for a property, it’s easy to be drawn in by the location, the views or the layout. But there is one factor that affects your daily life directly and constantly: energy efficiency. An efficient home uses less energy to stay comfortable, and you notice it both in your bills and in how the home feels.
What “energy efficiency” really means in a home
Energy efficiency is a home’s ability to maintain comfortable conditions (temperature, humidity, ventilation) while using as little energy as possible. It depends on three main factors:
- The thermal envelope: walls, roof, floor slab and window frames. The better they insulate, the less energy you need to heat or cool.
- The installations: heating, cooling, hot water and ventilation. Efficient equipment does more with less.
- Bioclimatic design: orientation, solar shading and natural ventilation. Good design reduces reliance on mechanical systems. We explain it in how a property’s orientation affects your daily life.
In a new build, these three factors can be worked on together from the design stage, which is much harder to achieve when renovating an older home.
The difference you notice every day
Energy efficiency translates into tangible experiences that shape your routine:
In winter
A well-insulated home keeps a more stable indoor temperature without constant heating. There are fewer cold walls and fewer draughts around the windows. Aerothermal heating with underfloor distribution, common in new builds, spreads warmth evenly and quietly.
In summer
Insulation works both ways. A home with a good envelope and solar protection stays cooler for much of the day, so you use the air conditioning less.
Year-round
Controlled ventilation renews the air without opening the windows, which is useful on windy or very hot days. Reducing thermal bridges helps prevent condensation and mould, and good window frames also keep outside noise out.
💡 Key fact: real savings depend on the home, its orientation and your habits. To compare properties, look at the primary energy consumption (kWh/m² per year) shown on the energy certificate: the lower it is, the less energy the home needs.
Energy certification: what the letters mean
In Spain, every home that is sold or rented must have an energy performance certificate, under Royal Decree 390/2021 (in Spanish). The scale runs from A (most efficient) to G (least efficient) and assesses primary energy consumption and CO₂ emissions.
Because of the current requirements of Spain’s Technical Building Code, new homes tend to achieve high ratings, while many older homes have lower letters. You can find more details on the certification system on the IDAE website.
What to look for in the certificate
- Overall rating: the general letter. A and B indicate high efficiency.
- Primary energy consumption: measured in kWh/m²·year. The lower, the better.
- CO₂ emissions: measured in kgCO₂/m²·year. Relevant if you care about environmental impact.
- Improvement recommendations: the certificate includes suggestions, useful if you buy resale.
The elements that make the difference
Thermal insulation
The component with the biggest impact on consumption. New builds use systems such as external continuous insulation (ETICS/SATE) or insulated cavities that reduce thermal bridges.
Window frames and glazing
Windows are the weakest point of the envelope. Thermal-break frames (RPT aluminium or PVC) with low-emissivity, solar-control double glazing let in less heat in summer, less cold in winter and less noise.
Aerothermal systems
Aerothermal technology is a heat pump that extracts energy from the outside air to heat or cool the home and produce hot water. For every unit of electricity it uses it can deliver several units of thermal energy; its performance (COP) is shown on each unit’s technical data sheet.
Underfloor heating and cooling
Combined with aerothermal heat pumps, underfloor systems spread heat (or cooling) evenly and at low temperature, improving the system’s efficiency and avoiding the hot and cold spots of radiators and split units.
The economic impact: beyond the monthly saving
Energy efficiency doesn’t just reduce your electricity bill:
- Fewer maintenance surprises: well-maintained modern systems tend to cause fewer problems than old installations.
- More appeal when selling or renting: a good energy rating is a point in your favour with any buyer or tenant.
- Less exposure to energy price rises: the less you consume, the less they affect you.
- Possible tax relief: Spanish law allows town councils to reduce property tax (IBI) for homes with solar energy installations; check your municipality’s tax bylaws.
If you are comparing new builds and resale homes, you may also want to read what guarantees a new-build property offers. And if you’d like to see homes built to these standards, take a look at our new-build developments in eastern Mallorca.
Frequently asked questions about energy efficiency in housing
Is it worth paying more for an efficient home?
It depends on the extra cost and how long you plan to live there. Compare the primary energy consumption on each home’s certificate and estimate what you would spend a year in each; then add the comfort and the better position if you ever sell or rent.
Are new-build properties in Mallorca genuinely efficient?
Those that comply with the current Technical Building Code start from much higher efficiency requirements than homes built a few decades ago. Even so, check each development’s specifications and expected energy rating.
Can I improve the efficiency of a resale property?
Yes. Replacing window frames and adding external insulation are the most effective measures, but the cost varies a lot depending on the size and condition of the home, so get quotes before deciding.
How can I tell whether a property is truly efficient before buying?
Ask for the energy performance certificate and review the specifications. Look for concrete data: type and thickness of insulation, frame type, climate control system and energy rating.