Building a house with separate apartment: funding from the state

The most important requirement for saving costs is that your granny flat is actually a real granny flat. Different requirements apply here compared to, for example, condominiums. They are, by definition separate rentable apartments in a building where otherwise only you as the owner live.

A granny flat always has a separate entrance and is clearly separated from the rest of the house. It includes its own kitchen, toilet and its own connection to the heating system. Also note: it must be at least 23 square meters! Furthermore, increased noise and fire protection is required.

Energy efficient granny flat – double financing

A granny flat is especially useful if you are planning an energy-efficient new build. The “Energy Efficient Building” program. KfW Bank supports efficient homes with a low-interest loan of up to 50,000 euros per housing unit. Because the Granny Flat is a separate living unit in your condominium, you will receive double the financing.

In addition to meeting the requirements for granny flats, you must ensure that you comply with the KfW financing guidelines: Depending on the financing program, a certain energy efficiency must be achieved. As of KfW 70, the requirements of the Energy Savings Ordinance (Enev) are no longer met. This is beneficial in two respects: it makes it easier for you to finance the building and it saves you on energy costs in the long term.

Tax relief through separate living spaces

Unlike an apartment that only you use, your own house with a separate apartment also saves you on taxes: just compare your income and expenses on your tax return. THE Losses must be claimed for tax purposes.

For example, costs for:

Apartment financing
Repairs or maintenance and maintenance work
Heating and electricity
Waste disposal

and much more. It is important that these can be clearly assigned to the tax office a separate account for the grandmother’s apartment drive. Contracts and invoices, such as those for electricity and heating costs, are also best presented separately.

Of course there are also tax breaks if you rent the apartment to close relatives. All you need to do is make sure you sign a proper contract and that the rent isn’t too low! If this is less than 66% of the local comparative rent, you can only deduct part of the costs from your taxes.

Perfect insurance for different life situations

In addition to the economic benefits separate living space in your own home But there is another great advantage: it offers perfect protection in different life situations. If your house is to become a generational home or if you need an apartment for elderly nursing staff, the granny flat facilitates changes in your life.

Conclusion

Creating a separate living space within your own home provides far more than just economic advantages—it adds flexibility, security, and long-term peace of mind. A well-designed granny flat or secondary suite can easily adapt to the changing stages of life, offering a practical solution for evolving family needs. Whether you plan to accommodate aging parents, provide space for a caregiver, or offer independence to grown children, this additional unit ensures that your home remains functional and inclusive for everyone.

From a financial perspective, a separate living area can generate extra income through rental opportunities or increase the property’s market value. However, its greatest benefit lies in the comfort and support it offers in various life situations. For example, when used as a space for elderly care, it allows loved ones to stay close while maintaining privacy and autonomy. Alternatively, if the home transitions into a multigenerational residence, the design encourages connection while still providing each member their own personal retreat.

Furthermore, integrating a granny flat promotes sustainable living by making efficient use of existing land and resources. Instead of building separate homes, families can share infrastructure and reduce overall energy consumption. With proper planning, sound insulation, and independent access, this space can deliver both comfort and functionality without compromising the main home’s design or flow.

In conclusion, a separate living unit within a home represents a forward-thinking approach to modern housing. It provides not only financial benefits but also adaptability and emotional support throughout the different stages of life. By planning such a space thoughtfully, homeowners can create a versatile environment that meets current needs while remaining prepared for whatever the future may bring.