The question “underfloor heating or radiators?” is usually framed as a comfort choice. It is not. It is an operating cost decision — and, increasingly, a future-proofing one.

The technical difference is in operating temperature. A radiator system requires water heated to 50–75°C to deliver adequate heat output. An underfloor system distributes heat through a large surface area and operates effectively at 27–35°C. Lower temperature means less energy consumed to reach the same result. Romanian market data puts the average annual energy saving at around 20%; EU studies on hybrid systems place the range higher, at 25–40% depending on building insulation quality.

For a rental investment, that saving flows primarily to the tenant — which is the correct framing. Lower heating bills increase the unit’s attractiveness relative to comparable stock. Better-quality tenants, lower vacancy risk, more stable yield.

The future-proofing argument is separate, and in some ways more significant. The EU’s Energy Performance of Buildings Directive is pushing residential heating toward electrification — specifically heat pumps — by the 2030s. A heat pump paired with a radiator system requires water at 55–60°C to perform adequately, which erodes efficiency gains significantly. A heat pump paired with underfloor heating operates in its optimal range at 35°C. Buildings with underfloor systems are already compatible with the next generation of heating infrastructure. Buildings with radiators will require either system replacement or efficiency compromise.

The installation cost is higher. The question is what you are comparing it against.