1. Modern Engineering Systems §

New residential buildings in Switzerland are increasingly defined by centralized, energy-efficient engineering systems rather than individual boilers or ad-hoc solutions. For buyers, understanding these systems matters not only for comfort and running costs, but also for long-term maintenance, resale value, and regulatory compliance.

This chapter provides a practical overview of the main technical systems you will encounter in modern new-build apartments and what they mean for you as an owner.

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Heating and Cooling §

Heat Pumps §

As of 2025, heat pumps are the standard heating solution in most new Swiss residential developments.

All heat pumps work on the same principle: they extract low-temperature heat from the environment and raise it to a usable temperature for space heating and hot water. The key difference lies in where the heat comes from.

Common types §

• Air–water heat pumps (same principle as normal AC)

  • Extract heat from outside air
  • Lower installation cost and simpler permitting
  • Slightly less efficient during very cold winter days

• Ground-source (geothermal) heat pumps

  • Use boreholes or ground loops in the ground
  • Higher upfront cost
  • Very stable efficiency year-round, independent of air temperature

• Hybrid systems

  • Combine a heat pump with district heating or a backup system
  • Often used where district heating is available but seasonal flexibility is desired
  • District heating itself is usually reliable and competitively priced, but hybrids add redundancy and peak-load security

Heat pumps typically supply:

• Underfloor heating
• Domestic hot water
• As of 2025, also passive cooling in summer

Heating systems §

In modern projects, underfloor heating often means more than pipes spread evenly across the slab. Designers frequently add extra loops in perimeter zones, along window fronts, or directly in the concrete ceilings.

Typical combinations include:

• Floor-heating loops at window fronts and outer edge zones
• TABS / thermally activated concrete slabs or other ceiling-embedded loops

These systems also run at low temperatures, which makes them a good match for geothermal and heat-pump installations.

In winter, loops along large window areas help keep the zone near the windows warmer. This reduces the cold feeling you often get beside them and helps limit downdraught from window fronts.

TABS / ceiling activation uses the same principle across a larger surface: the concrete slab itself becomes a thermally active mass. This delivers very even temperatures, but it reacts more slowly than point-source heating systems.

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Cooling systems §

Active air conditioning is uncommon in Swiss residential buildings. Instead, comfort in summer is achieved through a combination of passive measures:

• Passive cooling (free cooling) using ground loops
• Night ventilation via mechanical systems
• Solar shading (blinds, shutters)
• Thermal mass of concrete structures

In buildings with geothermal systems, free cooling works by circulating naturally cool ground temperatures through the low-temperature floor circuits or thermally activated ceiling slabs without running a compressor. This provides gentle cooling with minimal energy use.

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Ice Storage Systems §

Ice-storage systems are rare but technically advanced solutions found in some flagship developments.

How they work §

• A large underground water tank is installed
• Heat pump extracts heat from the water
• As the water freezes, it releases additional energy (latent heat)
• The tank is re-heated using:
  • Solar thermal energy
  • PVT panels
  • Ambient air

This allows the system to store energy seasonally and operate efficiently year-round.

Why developers use them §

Advantages

• High overall efficiency, measured via Seasonal Performance Factor (SPF)
• No deep geothermal drilling required
• Works well with renewable energy sources

Challenges

• Complex control logic and planning
• Higher upfront cost due to tank construction and integration
• Requires experienced designers and operators

Ice-storage systems can perform extremely well—but only if correctly sized and professionally managed.

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Hot-Water §

Centralized Hot-Water Production §

In modern apartment buildings, hot water is almost always produced centrally and distributed to individual units.

Typical setups §

• Heat-pump hot-water tanks
  Large insulated tanks heated by the central heat pump.
  → Efficient, but recovery time matters if many apartments draw hot water simultaneously.

• Combined heating + hot-water systems
  One integrated system serves both underfloor heating and hot water.
  → Efficient design, but requires good dimensioning.

• Solar thermal support
  Roof-mounted collectors assist hot-water production.
  → Less common than PV, but still used in some projects.

What buyers should know §

• Circulation systems mean hot water arrives quickly at the tap
  → Comfort benefit, but slightly higher energy losses (already accounted for in modern designs)

• Individual metering means you pay only for your consumption
  → Important in mixed-use or investor-heavy buildings

• Legionella protection is handled automatically
  → Systems periodically heat water to higher temperatures
  → This is a technical compliance issue, not something buyers must manage

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Renewable Energy §

Photovoltaics (PV) §

Solar panels are now standard in new residential buildings.

Electricity generated is typically used for:

• Common areas (lifts, lighting)
• Heat pumps
• Partial apartment consumption

Self-consumption models (ZEV) §

A self-consumption community (ZEV) allows multiple apartments to share locally produced solar electricity.

What this means for buyers:

• You consume solar power before buying from the grid
• Lower electricity costs
• Transparent allocation via smart meters

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PVT and Advanced Systems §

PVT panels combine:

• Electricity generation (PV)
• Heat extraction (thermal)

The thermal energy is used to support heat pumps, improving overall efficiency—especially in winter.

Other emerging concepts:

• Seasonal storage (thermal energy stored over months)
• Battery systems for peak-load smoothing (not full off-grid operation)
• Grid-friendly load management

These systems aim to reduce grid stress and operating costs, rather than provide full energy independence.

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Ventilation §

Mechanical Ventilation with Heat Recovery §

Modern apartments are airtight by design. To maintain air quality, they use mechanical ventilation with heat recovery.

Heat recovery means:

• Warm exhaust air transfers its heat to incoming fresh air
• Fresh air enters already pre-warmed
• Energy losses are minimized (often 80–90% recovery)

Typical system characteristics §

• Fresh air supplied to living rooms and bedrooms
• Stale air extracted from kitchens and bathrooms
• Filters remove pollen and fine dust

System types §

• Centralized systems

  • One system for the entire building
  • Lower maintenance for individual owners
  • Less individual control

• Apartment-level units

  • Individual control per apartment
  • Easier fault isolation
  • Slightly higher maintenance responsibility

Some projects supply fresh air only to living rooms and bedrooms—this is acceptable if correctly designed.

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Ventilation Matters §

Modern, highly insulated buildings are nearly airtight. Without controlled ventilation, this can lead to:

• Elevated CO₂ levels
• Moisture buildup
• Mold growth
• Persistent odours

In this case, opening windows alone is not sufficient for air quality control. Ventilation systems are a core part of the building concept, not an optional extra.

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Facades and Building Envelope §

The façade is not only about appearance. In a new-build apartment, the exterior wall system directly affects:

• Moisture safety
• Summer comfort
• Acoustic performance
• Maintenance costs
• How the building ages visually over 20–50 years

In Swiss apartment constructions, the most common standard façade is the external thermal insulation composite system (ETICS, often called Kompaktfassade): mineral wool fixed to the exterior wall and finished with reinforced plaster/render. Ventilated façades exist as well, but they are usually the more premium and less common option.

ETICS (Kompaktfassade) §

Typical build-up:

• Structural wall in concrete or masonry
• Mineral wool insulation fixed directly to the wall
• Reinforcing layer with mesh
• Finish coat in plaster/render

Why it is so common:

• Cost-efficient and standardized

  • Cheaper than ventilated cladding.
  • Contractors and suppliers use it routinely across Switzerland.

• Good thermal performance

  • Mineral wool provides strong insulation and also helps with fire performance and acoustics.

• Slim wall build-up

  • No ventilated cavity or cladding substructure is needed.

• Clean visual appearance

  • Easy to achieve a uniform rendered look across a whole development.

What buyers should watch:

• More sensitive outer surface

  • Render can crack, chip, stain, or develop algae over time.

• Less forgiving if water gets behind the finish

  • Drying is slower than in a ventilated façade.
  • Window reveals, balcony connections, and penetrations must be detailed carefully.

• More visible maintenance cycle

  • Cleaning, repainting, and local render repairs may be needed sooner than with panel cladding.

• Impact damage

  • Ground-floor zones and balcony-adjacent walls can be more vulnerable to knocks and dents.

Masonry Cavity Wall / Double-Shell Wall §

Some buildings use a double-shell wall with an outer masonry leaf and cavity. This is more common in certain house types or region-specific construction traditions than in standard developer apartment blocks.

Typical strengths:

• Very robust outer layer
• Good acoustic mass
• Long service life

Typical weaknesses:

• Thick wall build-up
• Higher material and labor cost
• Less flexibility for modern panel-based façade design

Prefabricated Concrete or Sandwich Panels §

Larger projects sometimes use prefabricated façade elements with insulation integrated in the panel.

Typical strengths:

• Fast installation
• Good factory quality control
• Durable exterior surface

Typical weaknesses:

• Joints become critical
• Repairs and later modifications become more difficult
• Appearance feels more repetitive unless carefully designed

Ventilated Facade §

A ventilated façade (hinterlüftete Fassade, often called a rainscreen façade) has a physical air cavity between the insulation and the visible outer cladding.

Typical build-up:

• Structural wall in concrete or masonry
• Insulation fixed to the wall
• Ventilated air gap, usually around 20-40 mm
• Outer cladding in fiber cement, metal, ceramic, stone, HPL, or timber

The cavity is open at the bottom and top so air can circulate. This allows the system to dry more easily if wind-driven rain or condensation reaches the back of the cladding.

Advantages §

• Better moisture management

  • The cavity helps remove trapped humidity and incidental water.
  • This makes the system more forgiving than Kompaktfassade / ETICS.

• Better summer behavior

  • Sun heats the outer cladding first.
  • Part of that heat is carried away by rising air in the cavity before it reaches the insulated wall.

• Higher durability

  • Cladding panels expand and contract more freely than rendered surfaces.
  • This reduces the risk of visible hairline cracking.

• Lower maintenance over time

  • Individual panels can often be replaced locally.
  • The finish usually does not need repainting as often as rendered façades.

• Often better acoustics

  • The decoupled outer skin and mineral insulation can improve sound reduction, especially near busy roads.

The downside §

• Higher upfront cost

  • The cladding needs a substructure in aluminum, galvanized steel, or timber.
  • Installation is more complex than a standard rendered façade.

• More detailing risk

  • Fire barriers, cavity closures, corners, and window reveals must be designed and executed correctly.
  • A badly detailed ventilated façade can still leak or whistle in strong wind.

Comparison at a Glance §

Aspect	Kompaktfassade / ETICS	Ventilated façade
Upfront cost	Lower	Higher
Moisture robustness	Good if perfectly sealed, but less forgiving	Better drying and drainage reserve
Summer heat handling	Relies mainly on insulation and shading	Cavity helps vent away part of solar heat
Crack resistance	Render can show hairline cracks over time	Cladding usually handles movement better
Maintenance	Render cleaning and repainting may be needed sooner	Usually lower, with local panel replacement possible
Repairability	Local repairs can remain visible	Damaged panels can often be swapped individually
Typical market position	Standard	More premium

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Engineering systems directly influence:

• Energy costs
• Summer comfort
• Indoor air quality
• Maintenance effort
• Long-term value

You don’t need to master the technical details—but you should understand which systems are used and why.

In the following chapters, we explain how these systems relate to Minergie, SNBS, energy certificates, and what owners are responsible for once the building is in operation.