Main takeaways

• Renovations to reach high energy standards are extremely costly. Even with loans and subsidies, total project costs for full-energy overhauls ranged here from about €31,000 to €275,000, and families still needed to draw on large personal savings or unpaid labour. Subsidies (premies) covered only a small fraction of total spend — typically under 10%.

• Access to favourable financing helps but is limited and conditional. Interest‑discounted or interest‑free renovation loans made projects feasible for these households, but such schemes often require timely completion to retain benefits, force prefinancing of works, and may no longer exist in the same form. Loan rules and timing add financial risk (repayment, penalties, or losing interest subsidies) if deadlines or technical targets aren’t met.

• Grants are helpful but unpredictable and administrative-heavy. Claiming Flemish premies required substantial paperwork, waiting times and prefinancing — meaning homeowners must front the full cost and only later recover part of it. Grants are means‑tested, so rising household income can reduce or eliminate eligibility even if the works were paid years earlier at a lower income level.

• Penalties for missing deadlines — though smaller than the remaining upgrade costs in some cases — create incentives where renovaters pay fines rather than complete unaffordable works.

• Savings on energy bills are real but modest. Homeowners reported month-to-month reductions (€10–15), but full payback on major investments like heat pumps or deep insulation can take decades and depends on future electricity prices and usage.

In conclusion, even motivated, financially prepared households may find it hard to comply with 2050-aligned standards.