By 2030, your class F property cannot be rented. Literally. The EU EPBD recast (2024) requires Portugal to ensure all properties rated F and G are renovated. How much will you lose in rent? And what does it cost to fix now versus later?

This is not a guide on how to obtain an energy certificate. It is an analysis of how a regulation with a fixed deadline rewrites the ROI of any residential property in Portugal — and where the opportunity lies for investors who run the numbers before the crowd does.

Summary: F and G rated properties face a 2030 rental deadline. Investors who buy now at a discount, renovate to B/C, and requalify the asset capture a value premium (5–15%), a rent premium (8–12%), and avoid the risk of regulatory obsolescence. Waiting costs money. Acting now creates spread.

The 2030 deadline that changes everything

Decree-Law 101-D/2020 already requires an energy certificate to be presented in every property listing for sale or rent. The fines are real: €250 to €3,740 for individuals, €2,500 to €45,000 for agencies. But that is the past. The present is the EPBD recast, approved by the European Union in 2024, which goes further: properties rated F and G must be renovated by 2030. Without a valid certificate showing a minimum E rating (and moving towards D in later phases), the property loses its legal capacity to generate rental income.

For an investor, this means three concrete things:

  • Zero rental income from 2030 if the property is not renovated and remains rated F or G.
  • Accelerated depreciation as 2030 approaches and the market prices in the regulatory risk.
  • Acquisition opportunity at a discount now, while sellers ignore or underestimate the impact.

Portugal's SCE (Energy Certification System for Buildings) confirms that most properties built before 1990 classify between D and G. In other words, the available stock trading at a discount is large — but the window to act is closing.

Most investors still treat the energy certificate as a €150 administrative cost. By 2027, those same investors will discover that the certificate is the thermometer of asset value. Anyone without a plan to exit F/G is buying a liability with an expiry date.

The numbers: cost, premium, and payback

Quantifying the works is the first step. A jump from F to B on a typical 2-bedroom flat (70–85 m²) normally involves three fronts: double-glazed windows, external wall/ceiling thermal insulation, and replacing the heating system with a heat pump. The estimated cost ranges from €8,000 to €25,000, depending on the building's condition, the scope of perimeter work, and material choices.

InterventionEstimated cost (2-bed)Rating impact
Double-glazed windows€2,500 – €5,000+0.5 to 1 class
External wall insulation (ETICS)€3,000 – €8,000+1 to 2 classes
Air-source heat pump€2,500 – €6,000+0.5 to 1 class
Roof/floor insulation€1,000 – €4,000+0.5 to 1 class
Full project (F→B)€8,000 – €25,0003–4 class jump

On the revenue side, the data is clear. There is a value premium of 5% to 15% between A/B and F/G properties in the same area, confirmed by European market studies and consistent with observations in Lisbon and Porto. For rentals, A/B properties command 8% to 12% more rent than equivalent F/G properties — tenants pay for thermal comfort and lower energy bills.

The payback calculation is where the decision reveals itself. For a 2-bed rented at €1,000/month, a 10% increase represents €100/month or €1,200/year. Against a €15,000 renovation, the payback from rent alone is roughly 12.5 years. But that ignores capital appreciation: if the property is worth €150,000 and gains an 8% rating premium (€12,000), the effective payback drops to 3–4 years when combining rent and value.

Strategic insight: The payback on energy works is not measured by rent alone. The value premium on resale is where the investor captures return. Buying F at a discount, renovating to B, and revaluing is the central thesis of renovation ROI applied to energy regulation.

The strategic decision: buy and renovate vs buy ready

The question that matters: buy a 2-bed rated F for €150,000 and invest €15,000 in works, or buy a 2-bed rated B for €180,000 ready to rent? Let us look at the numbers side by side.

ScenarioAcquisitionEnergy worksTotal investedPost-work valueMonthly rentCash-on-cash
Buy F + renovate€150,000€15,000€165,000€168,000 – €172,000€1,1006.5 – 7.5%
Buy B ready€180,000€0€180,000€180,000€1,1004.5 – 5.0%
Buy G + renovate€135,000€22,000€157,000€162,000 – €170,000€1,0807.0 – 8.5%

The buy-and-renovate scenario invests less total capital, generates immediate equity (post-work value above total invested), and produces a higher cash-on-cash return. The buy-ready scenario offers simpler execution and zero construction risk, but the investor pays the full premium without capturing spread.

The advantage is clear — but it comes with conditions. For the strategy to work, three factors must align:

  • Controlled renovation costs. With construction costs rising 5.9% year-on-year (INE, April 2026), the contingency budget should be 20–25%, not 10%. Use the renovation ROI calculator to stress-test.
  • Short execution timeline. If the works take 8 months instead of 4, you lose rent and costs escalate. Municipal licensing can add 60–90 days of delay.
  • Confirmed rating jump. Before buying, commission a pre-diagnostic energy assessment (€200–€400) to validate that F→B is achievable within the planned budget.

For investors who use break-even rent as a metric, remember: the post-renovation rent must cover not only the mortgage payment and operating costs, but also amortise the renovation investment within an acceptable timeframe. If the total payback (rent + value) exceeds 5 years, the regulatory and execution risk starts to erode the spread.

There is also a tax consideration. Energy efficiency works may qualify for benefits under the tax regime applicable to investors, including IRS or IRC deductions and, in some municipalities, IMI reductions for properties certified A or B. Always confirm with a certified accountant which conditions apply for the relevant tax year.

For a broader view of how energy rating interacts with rental yield across different Portuguese markets, the rating premium compounds with location choice — an A-rated flat in a high-yield secondary city outperforms on every metric simultaneously.

Frequently asked questions

What happens to class F and G properties in 2030?

The EU EPBD recast directive of 2024 requires Portugal to ensure all properties rated F and G are renovated by 2030. Without renovation, these properties cannot be legally rented, meaning zero rental income and accelerated depreciation.

How much does it cost to improve the energy rating of a 2-bed?

A jump from F to B on a 2-bed can cost between €8,000 and €25,000, depending on the building's condition, window replacement needs, thermal insulation, and heating system. Air-source heat pumps, wall insulation, and double glazing are the highest-impact interventions.

Are properties with better energy ratings worth more?

Yes. There is a 5% to 15% value premium between A/B and F/G properties in the same area. For rentals, A/B properties can command 8% to 12% more rent than equivalent F/G properties.

Is it better to buy a cheap F/G property and renovate or buy a ready A/B property?

It depends on the price spread, actual renovation costs, and execution timeline. Buying F/G at a discount and renovating can yield 6–9% cash-on-cash, versus 4–5% for a ready A/B property. But execution risk (cost overruns, delays, licensing) should be priced in with a 20–25% contingency.

Sources

  • Decree-Law 101-D/2020, Energy Certification and Air Conditioning System in Buildings, accessed via SCE Portal, 2026-07-11.
  • Directive (EU) 2024/1275 of the European Parliament and of the Council (EPBD recast), on the energy performance of buildings, accessed 2026-07-11.
  • SCE — Energy Certification System for Buildings, Portal das Finanças, accessed 2026-07-11.
  • INE, Index of New Housing Construction Costs, April 2026, accessed 2026-07-11.