Prefab House Glossary: the Most Important Terms from A to Z

Anyone getting to grips with prefab house (Fertighaus) construction quickly runs into a flood of technical terms: from the fit-out level to the specification of works to the interim financing. Many decisions depend on you understanding these terms correctly – especially when comparing offers and reading the construction contract. This glossary explains the most important terms around prefab houses, planning, financing and construction briefly and in plain language, sorted alphabetically by letter groups. That way you can quickly find the right definition and reach the in-depth guide directly via the cross-references.

Terms from A to E

Fit-out level (Ausbaustufe)

The fit-out level describes how far a prefab house is completed at handover – from the kit house through the shell-completion house to the turnkey house. It is the most important price lever: the more work you take on yourself, the cheaper the purchase price. An overview is provided by the fit-out levels guide.

Shell-completion house (Ausbauhaus)

A shell-completion house is only partly finished by the manufacturer – typically wind- and weatherproof, while you take on the interior fit-out yourself, such as screed, floor coverings or painting work. This lowers the price, but requires manual skill and time. More on this in the hub Shell-completion house.

Specification of works (Bauleistungsbeschreibung)

The construction or specification of works lists all the services and materials that are included in the house price. It is the most important document when comparing offers, because the provider only owes what is written here. What matters is shown by the guide on checking the construction contract.

Ancillary construction costs (Baunebenkosten)

Ancillary construction costs are all the costs incurred in addition to the pure house price – for example property transfer tax, notary, servicing, building permit (Baugenehmigung) and outdoor facilities. As a guide value for 2026 you should budget around 15 to 20 % of the total budget. Details are provided by the ancillary construction costs guide.

Selection meeting (Bemusterung)

At the selection meeting you choose the specific specification of your house – tiles, doors, floor coverings, sanitary fixtures and more. Anyone who goes beyond the standard pays surcharges that can noticeably raise the final price. How to prepare is explained by the selection-meeting checklist.

Floor slab (Bodenplatte)

The floor slab is the foundation on which the prefab house is erected. It is frequently not included in the house price and has to be commissioned separately. As a guide value for 2026, the costs, depending on the ground conditions, are around €15,000 to €30,000. Check in the offer whether the floor slab is included.

Servicing (Erschließung)

Servicing refers to the connection of the plot to electricity, water, sewage, gas and telecommunications, as well as the link to a public road. Without servicing a plot cannot be built on. What you should watch out for when buying is set out in the guide Finding & assessing a plot.

Terms from F to J

Fixed price (Festpreis)

A fixed price guarantees that the agreed house price will not change over a certain period. It protects against additional claims – but only for the services set out in the specification of works. Watch out for the price-binding period and for what is expressly not included.

Prefab house (Fertighaus)

A prefab house is prefabricated in individual components or modules in the factory and assembled on the building site. This considerably shortens the build time and allows weather-protected production. How this differs from solid construction is shown by the guide Prefab house vs. solid construction. A compact introduction to the topic is provided by the page Prefab house overview.

Subsidy (Förderung)

Subsidies include low-interest loans and grants, for example from the KfW, for energy-efficient or family-friendly building. The programmes change regularly and are tied to specific conditions. The current status is summarised by the guide KfW subsidy 2026.

GEG (Building Energy Act, Gebäudeenergiegesetz)

The Building Energy Act sets out the minimum energy requirements a new build must meet – for example on insulation and heating technology. Prefab houses usually meet these requirements as standard. The GEG therefore influences both the construction costs and the later energy costs.

Floor plan (Grundriss)

The floor plan is the scaled top-down view of the room layout of a storey. A well-thought-out floor plan determines everyday usability, the flow of light and later flexibility. Many prefab manufacturers offer adaptable floor plans – ask to be shown variants for different phases of life.

Timber-frame construction (Holzständerbauweise)

Timber-frame construction (also called timber-frame building, Holzrahmenbau) is the most common construction type for prefab houses: a load-bearing timber frame is boarded and insulated on both sides. It is considered fast, energy-efficient and durable. More on the construction methods in the guide Choosing a construction method.

Terms from K to O

Purchase ancillary costs (Kaufnebenkosten)

Purchase ancillary costs are incurred when acquiring a plot or a property in addition to the purchase price: property transfer tax, notary, land register entry and, where applicable, estate agent commission. As a guide value for 2026 this is around 10 to 12 % of the purchase price. As a rule they must be paid from equity.

KfW

The KfW (Kreditanstalt für Wiederaufbau) is the state development bank that grants low-interest loans and grants for home ownership and energy-efficient building. Applications usually run via your own bank. Current programmes are explained by the guide KfW subsidy 2026.

Solid house (Massivhaus)

A solid house is built stone by stone from brick, sand-lime brick or concrete. It is considered robust and is erected piece by piece on site, which lengthens the build time. The comparison with the prefab house is set out in the hub Solid house and in the guide Prefab house vs. solid construction.

Modular house (Modulhaus)

A modular house consists of prefabricated room modules that are fully fitted out, set in place by crane and connected to one another. This shortens the build time on site to a few days. Floor plans and providers can be found in the hub Modular house.

Show house (Musterhaus)

A show house is a walk-through exhibition house of a manufacturer, often in a show-house exhibition. It conveys a realistic impression of the sense of space, the workmanship and the specification. What you should watch out for during the visit is set out in the show-house checklist.

Terms from P to T

Photovoltaics (Photovoltaik)

A photovoltaic system converts sunlight into electricity and is increasingly planned in directly for new builds. It lowers energy costs and can be combined with storage. In many federal states there is now an obligation to install one for new builds – check the requirements of your federal state.

Shell (Rohbau)

The shell comprises the load-bearing structure of a house: foundation, walls, ceilings and roof truss, without the interior fit-out. It marks an important milestone in the construction process. How the shell fits into the overall sequence is shown by the guide on the house-building process.

Turnkey (Schlüsselfertig)

Turnkey means that the house is handed over ready to move into – however, the term is not legally defined. Exactly what is included follows solely from the specification of works. Details are clarified by the guide Building turnkey.

Repayment (Tilgung)

The repayment is the portion of your monthly instalment with which you pay back the loan. A higher initial repayment shortens the term and lowers the interest costs. The basics of this are explained by the guide Construction financing 2026.

Type house (Typenhaus)

A type house is a standardised series model from the manufacturer with a fixed floor plan, which usually can only be adapted to a limited extent. Because the planning already exists, it is often cheaper than a freely designed house – a route that the guide Building cheaply also takes up.

Terms from U to Z

Handover / construction acceptance (Bauabnahme)

The construction acceptance is the moment at which you officially take over the finished house and record any defects in the report. The warranty period begins with the acceptance. Take your time and, in case of doubt, bring in an expert.

Heat pump (Wärmepumpe)

A heat pump uses ambient heat from air, ground or groundwater for heating and is considered the standard solution for new builds. It is efficient and is often combined with underfloor heating and photovoltaics. The purchase raises the construction costs but lowers the ongoing energy costs.

Works contract (Werkvertrag)

The works contract is the legal basis on which a house-building company owes a specific work – your house. For consumers the specially protected consumer construction contract (Verbraucherbauvertrag) often applies. What belongs in it is explained by the guide Checking the construction contract.

Living space (Wohnfläche)

The living space is the countable usable area of a house, calculated according to the Living Space Ordinance (Wohnflächenverordnung). It differs from the base area because, for example, sloping ceilings only count proportionally. When comparing offers, make sure that all providers use the same basis of calculation.

Interim financing (Zwischenfinanzierung)

Interim financing bridges a gap in time, for example when equity only becomes available later or a property is still being sold. It is usually more expensive than a regular loan and should be well calculated. How much equity makes sense is shown by the guide Equity when building a house.

How to proceed after the glossary?

As next steps we recommend the overview of house-building costs, the cost calculator for a first estimate, as well as the overview of the house types. Anyone still unsure will find good orientation in our manufacturer overview 2026.