Home Energy Efficiency: Classes, Costs & Incentives

Index

• What Energy Performance Means
• Energy Classes: from G to A4
• How to Improve Energy Efficiency
• Costs of Retrofit Measures
• 2025 Incentives & Tax Breaks
• EPC (APE): When It’s Mandatory & How to Obtain It
• Energy Performance: Timber vs Traditional

What Energy Performance Means

Energy performance is the set of metrics that show how much energy a building needs to heat, cool, provide hot water and light itself. The key figure is EPgl,nren (global non-renewable primary energy), expressed in kWh/m² per year: the lower it is, the more efficient the building. Knowing a home’s performance lets you:

• Estimate annual running costs.
• Plan targeted retrofit works.
• Raise the property’s market value.

Energy Classes: from G to A4

Italy uses an energy scale from G (worst) to A4 (best). Every class jump can cut consumption by 15 – 25 %.

• Class G: pre-1980 buildings, no insulation (EPgl > 200 kWh/m²).
• D – E – F: partially upgraded homes (110 – 200 kWh/m²).
• Class C: basic external insulation & double glazing (71 – 110 kWh/m²).
• Class B: efficient systems, some renewables (41 – 70 kWh/m²).
• Class A1 – A3: high-performance envelope, heat pump, MVHR (≤ 40 kWh/m²).
• Class A4: NZEB or passive house, near-zero load (≤ 15 kWh/m²).

How to Improve Energy Efficiency

Upgrading means acting on both envelope and systems. These are the five pillars:

Thermal insulation & external render

Adding an external or internal “cappotto” cuts heat loss by up to 40 %. Common materials: EPS, wood-fibre board, rockwool—chosen for climate, breathability and thermal mass.

High-performance windows

Replacing old frames with low-e triple-glazed units (Uw ≤ 1.0 W/m²K) eliminates draughts and thermal bridges, while boosting acoustic comfort and daylight.

Modern heating systems

Air-to-water heat pumps with underfloor heating reach COP > 4. Where renewables aren’t viable, condensing boilers remain an option.

Solar panels & photovoltaics

A correctly sized PV array can cover up to 70 % of electrical demand. Solar-thermal is ideal for DHW and heating support.

Mechanical ventilation with heat recovery

Double-flow MVHR (η > 85 %) supplies fresh air without opening windows, preventing mould and heat loss.

Costs of Retrofit Measures

• External insulation: € 90 – 140 /m².
• Triple-glazed windows: € 500 – 800 per m² of frame.
• Heat pump + UFH: € 130 – 180 /m² of floor area.
• 6 kWp PV system: € 8 000 – 10 000 (battery excluded).
• Central MVHR: € 3 000 – 6 000.

A full package ranges from € 250 – 400 /m²; typical pay-back is 7-12 years thanks to energy savings and incentives.

2025 Incentives & Tax Breaks

From 1 January 2025 the 50 % Ecobonus remains for energy retrofits, spread over 10 annual claims. For apartment blocks the rate rises to 65 %. Further measures:

• 50 % Window Bonus (cap € 60 000).
• Conto Termico 2.0 grants for heat pumps & solar-thermal (up-front rebate via GSE).
• 10 % VAT on materials & labour for renovations.

EPC (APE): When It’s Mandatory & How to Obtain It

The Attestato di Prestazione Energetica is required for:

• Selling or renting property.
• New builds or major renovations affecting > 25 % of the envelope.
• Accessing state incentives (Ecobonus, Conto Termico).

A licensed assessor surveys the building, calculates EPgl and registers the certificate with the regional database.

Energy Performance: Timber vs Traditional

Timber structures have lower thermal mass but achieve wall U-values ≤ 0.20 W/m²K with slim profiles. Masonry walls need extra insulation to match this. Timber also minimises thermal bridges through structural continuity, while masonry’s mass better dampens summer peaks. Optimum solution: hybrid climate-timber walls plus external shading and MVHR.

In short, combining a high-performance envelope with next-generation systems lets you climb the energy ladder, cut consumption and tap 2025 incentives—while boosting property value.