Home energy consumption: what should you renovate and when? | key4.ch

What kind of energy-saving measures make sense – and when?

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27.04.2023 | 3 minutes

Sooner or later, many owners of older properties are faced with the question of whether to invest in their home. It may need an update or refresh, or it could be that serious issues have made some comprehensive repairs or renovation necessary. But where should you start and how much money should you spend? Does it make financial sense to invest in your home in ecologically sustainable ways? And when is the right time to carry out which type of work?

Why regular renovation work is key to maintaining your home’s value

Whether it be minor repairs, the replacement of older appliances, or major investments such as insulating external walls and installing a new heating system to improve energy efficiency: as a property owner, you cannot avoid having to invest regularly in minor or major improvements or renovations. Regular investment is also key to maintaining the value of your house or apartment. The cost of maintaining your home will be roughly one percent of the purchase price of your property, as the following example shows:

  • Purchase price: CHF 1,5 million
  • Annual expenses for renovation: CHF 15,000

Sometimes there will be periods in which no investment is required, although this may mean you have to spend a lot of money a few years later.

An overview: when do which types of renovation work become necessary?

The following table illustrates when certain types of renovation work generally become necessary and can serve as a basis for planning sustainable renovations:

Item for renovation

Timing of renovation

Electronic equipment, electrical and water installations, interior walls, surfaces and floors (except tiled floors)

after 15–20 years

Kitchen worktops, bathrooms, windows, ventilation systems, plumbing, elevators, chimneys and flat roofs

after 20–30 years

Cellar and attic conversions

after 40 years

Pitched roofs, facades and heating systems

after 45–55 years

Complete remodeling or new construction

after 75–100 years

Houzy’s digital renovation calculator calculates costs and the ideal time to carry out the work

However, there is a smarter, more accurate way than the above overview to work out the right time to do the work. The Houzy digital renovation calculator will help you plan better and find out which investments will save you the most money. Houzy performs the following services for you:

  • Analyzes your real estate based on just a few details
  • Calculates the ideal time to invest
  • Calculates the approximate renovation costs

Even if individual items need to be renovated at different times, sometimes it makes sense to do certain types of work at the same time. Houzy will show you for which kinds of renovation work this would make sense, in order to achieve more cost-efficient results.

UBS Switzerland AG (“UBS”) has a stake in Houzy AG (“Houzy”). Through its strategic partnership with Houzy, UBS aims to expand its range in the Home & Living ecosystem. By clicking on this link, you will leave the UBS website. UBS has no influence on the data processing of the Houzy website and therefore does not assume any liability for it. UBS is generally not liable for services provided by Houzy.

How the different savings are calculated

The Houzy digital renovation calculator takes care of all the calculations central to your renovation work. It can still be helpful to know more about how these savings are calculated so that you can understand the recommendations better.

There are two different types of amortization:

  • Economic amortization: repayment of the purchase price using financial savings
  • Energetic amortization: the amortization of the energy used to manufacture an energy-generating installation

The economic amortization period shows how long it takes for the savings to offset the initial investment, such as the cost savings achieved by a new heating system. It is important to compare these against alternative investments. The following table shows the cost of acquiring an air-water heat pump compared to an oil-fired heating system and how high the annual heating costs are (source: energieheld.ch):

Type of heating

Costs of a new heating system

Annual heating costs

Air-to-water heat pump

CHF 32,000

CHF 1,000

Oil-fired heating system

CHF 27,000

CHF 2,200

So if you invest CHF 32,000 in a new heat pump and save CHF 1,200 annually, the amortization period is around 26 years. This is where the comparison with oil-fired heating comes into play. If you add up the costs of purchase and annual heating costs over several years, then after less than five years the total cost of the air-to-water heat pump is lower than that of the oil-fired heating system. The effective economic payback period for the air-to-water heat pump is therefore about five years. To keep things simple, fluctuating oil and electricity prices were not included in the calculation.

Manufacturing energy is also amortized in energy-efficient renovations

In addition to the economic savings, a climate-friendly renovation also pays off in energy terms. In order to make this saving apparent, energy amortization is often used. Energy amortization refers to the length of time it takes for a device to produce sufficient energy to balance out the energy required for its manufacture. For example, it takes around 1.5 to 3.5 years for thin-film solar panels to produce enough energy to compensate for the energy used in their manufacture.

Investing to make your home green will definitely pay off in the long term

Depending on your budget, there are several options for improvement or renovation work – from quick solutions to more comprehensive measures. Even if climate-friendly, energy-efficient renovation may seem expensive at first glance, it usually makes sense to make your home green. Not only are you making a significant contribution to the environment, you will also save money in the long term by increasing the quality of your home and because the cheaper operation of the installations and devices will pay off.

The UBS key4 mortgages Green Mortgage offers attractive mortgage conditions

There are several possible financial incentives for making a sustainable investment: in addition to subsidies at cantonal level, there are also attractive conditions for borrowing – the UBS key4 Green Mortgage really pays off. All you need to do is present your sustainability certificates to benefit from favorable mortgage conditions.

Does your property have a sustainability certificate?

Then please get in touch and we will check whether you are eligible for a Green Mortgage with a favorable interest rates.

Which renovation measures do the experts say are important?

Ecological building design is also an important factor in achieving the targets of the Federal Council’s Energy Strategy 2050. In order to assess the potential of various renovation measures, in 2019 the Urban Energy Systems research department at the Swiss Federal Laboratories for Materials Science and Technology Empa classified residential buildings according to year of construction, heating type and number of residents. The result shows that houses built between 1949 and 1994 have the most renovation potential. They represent the majority of all buildings in Switzerland and 77% of them are heated using electricity, oil or gas.

The researchers drew up a list of promising renovation measures accordingly. They concluded that in older housing stock, the renovation of roofs and windows should be tackled as a priority. This could reduce the demand for heating and cooling energy by between 20 and 30 percent. If all of the proposed measures – including those for businesses, schools, hospitals and offices – are implemented, greenhouse gas emissions could be reduced by as much as 60 to 80 percent throughout Switzerland.


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