How do I find out whether an old building is in need of renovation?

The 3-point checklist for remediation backlogs

Whether an old building is in need of renovation can be determined from three main indicators: firstly, the age of the building technology (heating systems over 20 years, electrical systems before 1990), secondly from the condition of the building envelope (cracks in the façade, damp basement walls, double-glazed windows) and thirdly from the energy classification (GEAK label E to G). If there are signs of moisture or if lead lines are still installed, there is a need for immediate action, which often drives renovation costs into the six-figure range.

The view from outside: The building envelope in focus

The building envelope is the first line of protection against the weather. In Switzerland, the temperature differences between summer and winter are a test for every material.

Roof and façade as cost drivers

A roof usually has a life cycle of 40 to 50 years. During the tour, check the attic:

• traces of moisture: Dark spots on the rafters indicate leaks.
• insulation: If there is no visible insulation between the rafters, the house no longer meets the energy standards of 2026.
• Facade cracks: Vertical cracks can indicate static problems, while mesh cracks are often just a sign of a need to repaint.

Windows: More than just glass

Pay attention to the spacers between the glass panes. If these are made of metal and the glass is “cold” to the touch, this is usually outdated double glazing. Modern windows (triple glazing) are standard to ensure the calorific value of the property and to minimize noise emissions (e.g. tram lines).

The inner values: technology, cables and electricity

What you don't see often costs the most. An old building can be visually perfectly renovated, while the pipes in the walls are on the verge of collapse.

Home technology and pipeline network

In Switzerland, galvanized steel pipes have a lifespan of around 30 to 40 years. This is followed by pitting and pipe bursts.

• The “rust test”: Turn on the water in an empty apartment. If it comes out of the tap brownish, the pipes are corroded.
• Elektrik: Check the fuse box. If old screw locks are still there instead of modern toggle switches (FI switches), the entire electrical system, including the cables in the walls, must be replaced for around 15,000 to 25,000 CHF.

Energy analysis: The GEAK as a gold standard

In 2026, the GEAK (cantonal building energy certificate) is already mandatory in many cantons such as Geneva or Vaud for changes of hands or is required by banks for mortgage lending (Saron or fixed interest rate).

Read the energy label

The GEAK rates the energy efficiency of the building envelope and overall energy efficiency on a scale from A (very efficient) to G (very inefficient).

• Category F/G: There is a massive need for renovation here. A heating replacement (e.g. heat pump) is often only useful if the shell is insulated at the same time.
• Category C/D: The property is in solid condition, but still offers potential for optimization for future funding.

Hidden hazards: pollutants and statics

Old buildings from the boom years (1950—1990) often contain an invisible legacy: pollutants. As part of your tenant due diligence or purchase review, you should mark these points in bold.

Asbestos and Radon

Until 1990, asbestos was used extensively in Switzerland — in tile adhesives, window putties or floor coverings.

• Restructuring obligation: Remediation under suspicion of asbestos requires specialized companies and increases costs by 20% to 30%.
• radon: In certain regions of Switzerland (foothills of the Alps, Jura), radon can diffuse from the soil into the cellar. Measurement is recommended for older cellars without a base plate.

Regional aspects: monument protection in cities

Zurich doesn't stop at Bellevue, and in cities such as Basel or Bern, entire districts are subject to townscape protection.

• building permit: An old building in need of renovation under monument protection means that you are not free to choose which windows or insulation you install. This can make the renovation more expensive by 30% to 50%.
• Utilization rate: Check whether the old building still has exploitation reserves. Renovation is often only profitable if an extension or extension can be completed at the same time.

Conclusion: System beats luck in an old building check

Finding out whether an old building is in need of renovation requires a combination of technical knowledge and digital data analysis. Don't rely on the “fresh paint” in the stairwell. A real renovation backlog is revealed in the basement, in the fuse box and in the GEAK report.

In summary, anyone who prepares their dossier for the purchase of real estate should definitely call in an expert for an inspection. The investment of around 1,500 CHF for a professional status analysis protects you against bad purchases in the millions. Use heyloft.ch's data power to find properties whose renovation history is transparent — your match for a historic but secure home is within reach with the right strategy.

glossary

• reference interest rate: The key indicator for your rent structure. Restructuring may result in rent increases based on this rate.
• Buying doesn't break rent: Your legal protection (Art. 261 OR). A buyer assumes the state of renovation and the existing rental agreements, but can register his own needs if renovation is required.
• Tenant due diligence: Your personal due diligence Analyze the GEAK report and the latest utility bills before moving in to assess the energy quality of the apartment.