Building a Four-Family House: Costs, Floor Plan, Plot (2026)

Four apartments in a compact form: how to plan a four-family house as a prefabricated house, calculate the cost per residential unit, estimate the plot requirement and choose the right access type (Spänner).

Request a multi-family house project – free & non-binding

Four-family house as a prefabricated house: costs, floor plan and plot at a glance — Four-family house as a prefabricated house – cost per residential unit, plot requirement and floor plan at a glance.

Direct answer

How much does a four-family house cost and what plot does it need?

A four-family house with around 360 sqm of living area costs, at a market range of 2,400 to 3,800 euros per square metre, roughly 864,000 to 1,368,000 euros for the building portion — that is about 216,000 to 342,000 euros per residential unit. With a site occupancy index (GRZ) of around 0.4, the plot requirement is roughly 400 to 520 sqm. All multi-family house models in our database are costed per project and offered with price on request. As of 2026, reference values.

Typical Plot Size for a Four-Family House

The plot requirement results from the permitted site occupancy index and the building footprint. With a GRZ of around 0.4, 40 percent of the plot area may be built on. A four-family house occupies about 150 to 190 sqm per storey. This gives a calculated plot requirement of roughly 400 to 520 sqm, including parking spaces, driveway and outdoor works.

In denser locations with a higher GRZ or more permitted storeys, the project needs less area. The development plan and the state building code are decisive. Before buying, it is worth doing the plot check to assess buildability and the permissible number of residential units.

Costs by Living Area and per Residential Unit

The total range is derived from the market range of 2,400 to 3,800 euros per square metre of living area, multiplied by the typical living area. The value per residential unit divides the total range by four apartments. These are reference values for the building portion, excluding the plot.

Living area	Market range	Total (building)	Per residential unit
320 sqm (compact)	€2,400 – €3,800/sqm	€768,000 – €1,216,000	€192,000 – €304,000
360 sqm (standard)	€2,400 – €3,800/sqm	€864,000 – €1,368,000	€216,000 – €342,000
400 sqm (generous)	€2,400 – €3,800/sqm	€960,000 – €1,520,000	€240,000 – €380,000

As of 2026, reference values. Building portion excluding plot, site servicing and outdoor works. Specific prices are project-based. More in the guide Multi-family house prices.

Cost Blocks at a Glance

Besides the building itself, the total costs are spread across several blocks. The percentage shares are typical orders of magnitude and serve as an initial guide.

Cost block	Typical share	Note
Building / construction (turnkey)	approx. 70 – 78%	Shell, fit-out, building services
Site servicing (Erschließung)	approx. 3 – 6%	Water, sewage, electricity, connections
Outdoor works	approx. 5 – 9%	Parking spaces, driveway, garden
Ancillary construction costs	approx. 12 – 18%	Planning, structural design, permit, fees

As of 2026, reference values. Shares vary depending on the plot and fit-out. Calculate with the cost calculator.

Floor Plan Concept: Four-Family House as a 2-Unit-per-Landing Layout Over Two Floors

A four-family house is often planned as a 2-unit-per-landing layout (2-Spänner): two apartments each on the ground floor and upper floor share a central stairwell. Alternatively, the 4-unit-per-landing layout (4-Spänner) groups all units on one floor. The diagram is not to scale.

A central stairwell (yellow) serves four apartments over two floors. Schematic illustration, Prefabricated House.

Sample Quick Yield Calculation

Suppose a four-family house with 360 sqm of living area costs around 1,250,000 euros including the plot. At an achievable net cold rent (Kaltmiete) of 12 euros per square metre, rental income amounts to around 51,840 euros per year. This gives a gross rental yield of about 4.1 percent. After deducting operating costs, maintenance and a rental-default allowance, the net yield falls accordingly.

Simplified model calculation, not investment advice. Plot and rent levels vary greatly by location. Tax effects such as declining-balance depreciation (degressive AfA) or the special depreciation under Section 7b EStG are not taken into account here. As of 2026; binding advice: tax adviser.

A Suitable Prefabricated-House Model with 4 Residential Units

This model from our database represents a four-family house. Because the plot, apartment mix and fit-out shape the price, it is costed per project and offered with price on request. This listing is not a ranking.

Model	Provider	Residential units	Living area	Storeys	Price
Multi — 4 residential units with flat roof	WeberHaus	4 residential units	approx. 360 sqm	3	Price on request

Living area as a rounded reference value of the example configuration according to the provider. Price is project-based, therefore on request. As of 2026.

Other Sizes in the Multi-Family House Cluster

Three-family houseThree apartments, a compact entry point Six-family houseSix apartments for investment properties Eight-family houseEight apartments for urban densification

An overview of type, construction method and providers is offered on the page Multi-family house. Example layouts and access types (Spänner) are shown by the multi-family house floor plans.

Building a Four-Family House: Frequently Asked Questions

Answers on costs, plot, access type (Spänner) and subsidies for the four-family house.

How much does it cost to build a four-family house?

For a four-family house (Vierfamilienhaus), a market range of roughly 2,400 to 3,800 euros per square metre of living area serves as a guide (as of 2026). For about 360 sqm of living area, this gives a rough total range of around 864,000 to 1,368,000 euros for the building portion, i.e. roughly 216,000 to 342,000 euros per residential unit. The plot, site servicing, outdoor works and ancillary construction costs come on top. Because the mix of apartments and the fit-out strongly influence the price, the prefabricated-house models are costed per project and offered with price on request.

How large does the plot for a four-family house need to be?

With a site occupancy index (Grundflächenzahl, GRZ) of around 0.4 and a building footprint of about 150 to 190 sqm per storey, the calculated plot requirement is roughly 400 to 520 sqm. Parking spaces, driveway and outdoor works are included. In denser locations with a higher GRZ or more storeys, less area is needed. The development plan (Bebauungsplan) and the state building code (Landesbauordnung) are decisive. The figures are reference values and do not replace an assessment of the specific plot.

What access type (Spänner) is a four-family house planned as?

A four-family house is often planned as a 2-unit-per-landing layout (2-Spänner) over two full storeys, with two apartments per floor served by a central stairwell. Alternatively, the 4-unit-per-landing layout (4-Spänner) groups all four apartments on one floor around a single stairwell, which reduces circulation area per unit but places higher demands on daylighting the inner apartments. The suitable type depends on the plot shape and the desired mix of apartments.

Is building a four-family house worthwhile as an investment?

A four-family house spreads the rental-default risk across four units and, thanks to its compact form, achieves good space efficiency. Whether the project pays off depends on the plot price, construction costs, achievable rent and financing. Tax instruments such as declining-balance depreciation (degressive AfA) or the special depreciation for new rental housing under Section 7b of the Income Tax Act (EStG) can improve the calculation. The conditions must be checked case by case. As of 2026; binding advice is provided by a tax adviser.

Does a four-family house need a lift?

A lift is required under building law in many federal states from three above-ground storeys. A four-family house over two full storeys usually manages without a lift. If the fourth apartment is placed on a third storey, the lift requirement may apply. A lift improves accessibility and the rentability of upper apartments but takes up space and incurs maintenance costs. The specific requirement follows from the respective state building code.

What subsidies are available for a newly built four-family house?

For newly built rental residential buildings, the main options are declining-balance depreciation, the special depreciation for new rental housing under Section 7b EStG, and subsidised loans under the KfW's climate-friendly new-build programme. The subsidies are tied to energy standards and deadlines and change regularly. Check specific interest rates and programme details individually. As of 2026; binding advice is provided by a tax adviser and the KfW.

Start Your Four-Family House Project

Get advice on the plot, floor plan and calculation, and receive suitable quotes from vetted manufacturers.