Check prefabricated house construction description: minimum specifications, gaps and checklist

The construction description is the decisive document when purchasing a prefabricated house – more important than any glossy brochure. It specifies which service is included in the price and anything that is missing there will be charged later. Anyone who wants to check a prefabricated house construction description should know the statutory minimum requirements according to Article 249 EGBGB, compare the scope of services of several providers and specifically search for the typical gaps. This guide provides a systematic checklist for this – and shows where an independent review can be obtained. Who to build turnkey wants to, should pay particular attention to the scope of the interior finishing trades in the construction description.

Minimum requirements according to Art. 249 EGBGB

Important: The legal requirement prescribes what must be described – not how high-quality it is built. A provider fulfills Art. 249 EGBGB even with a favorable standard as long as it describes it clearly. The construction description is thus primarily a transparency instrument, not a quality promise. This is exactly the most common fallacy when buying a prefabricated house: Many interested parties equate a detailed, professionally appearing construction description with high building quality. In fact the extent of the document initially only says something about the diligence of the description. Whether the described standard matches your requirements you must judge position for position yourself – or have it judged. These details must at least be included in 2026:

• General description of the building to be erected with floor plan, living area and room division.
• Type and scope of the offered services as well as explicitly excluded services.
• Building data, plans and information on building construction and building physics.
• Description of the interior finishing and the building services (heating, sanitary, electrical, ventilation).
• Information on the energy, fire protection and sound insulation standard.
• Binding information on the time of completion.

For the formal framework of the contract itself – revocation, payment plan, 90% limit – additionally read the guide Check prefabricated house contract as well as the general principles under Check building contract. Where the construction description stands in the entire purchase process is shown by the guide Buy prefabricated house.

A second aspect is often overlooked: The construction description becomes a contractual component. What is stated in it is what the company is obligated to provide – and only that. Brochures, show home impressions or verbal assurances from the seller are legally worthless as long as they are not incorporated into the construction description or the contract. Therefore insist that every verbally promised service is taken over in writing into the construction description. An older, generally worded construction description that shifts many details to the later "measurement" or to the "selection process" shifts the cost risk to you – with a transparently formulated description on the other hand quantities, qualities and brands are already fixed.

Compare scope of services: Why identical framework conditions count

A common error is the comparison of final prices without regard to the scope of services. The cheaper provider can become more expensive as soon as the missing positions are purchased subsequently. Therefore compare in a structured manner:

Prepare a simple table for the comparison: The trades are in the rows, the providers in the columns. This way you can see at a glance where one provider lists a position as included that another identifies as "by others" or "optional". Only this line-by-line comparison makes the final prices honestly comparable – and exposes seemingly cheap offers that are achieved through missing services. Pay particular attention to positions that do not appear in an offer at all: What is not mentioned is usually not calculated either.

Via our manufacturer comparison and the house catalogues you can request construction descriptions from several companies and lay them next to each other. We compare verifiable characteristics in doing so – without ranking, without test winner.

Typical gaps: earthworks, house connections, painting works

Scan the construction description specifically for the words “bauseits”, “not included”, “optional” and “nach Aufwand”. The later additional claims are hidden in these places. The most common gaps 2026:

Material selection: When the standard becomes a cost trap

Therefore require that the construction description contains an equipment performance specification with specific makes, price groups and quantities - sockets per room, tile area, sanitary objects, interior doors. We treat the contractual side of the material selection in depth in the guide Check prefabricated house contract. Pay attention to:

• Specific makes and price groups instead of “standard selection”.
• Quantities: sockets and switches per room, number of bathrooms, interior doors.
• Tile area and quality, floor covering per room type.
• Sanitary objects including fittings with manufacturer specification.
• Regulation whether unused material selection budget expires.

Read energy standard and house technology correctly

Especially for the prefabricated house in timber construction airtightness is a central quality feature. Check whether a blower door test is agreed and which target value should apply. For the heating system the construction description should not just name “heat pump” but specify make, output, storage size and whether a photovoltaic system is planned or only prepared. These details can hardly be renegotiated later without additional costs arising:

• U-values for external wall, roof, floor slab and windows - as specific numbers.
• Achieved efficiency house standard (e.g. EH 55/40) instead of only “GEG-compliant”.
• Heating system with make, output, storage and heating surfaces (underfloor heating).
• Ventilation: controlled living space ventilation with heat recovery - yes/no.
• Airtightness: blower door test agreed, target value specified.
• Photovoltaics and storage: included, only prepared or not planned.
• Electrical: number of sockets and circuits per room, pre-wiring for E-car.

How the execution of this technology is later controlled on the construction site is described in the guide Prefabricated house construction supervision. Because a good construction description is only useful if the company also implements the promised quality.

Have construction description checked independently

An independent review is particularly valuable for the construction description because laypersons often overlook the decisive omissions: A missing trade is less noticeable than a poorly formulated paragraph. An experienced expert reads the description against a reference list of complete trades and marks exactly the places where later supplements are threatened. Expect around 250 to 800 Euro for a construction description review in 2026 - a small investment measured against additional claims in the five-digit range.

A professional review uncovers gaps, unclear formulations and missing quantity specifications before you sign. Neutral contact points are the Verband Privater Bauherren, the Bauherren-Schutzbund and the IHK expert directory. We cover an accompanying control of the entire construction in the guide Prefabricated house construction support, the quality check in detail under Prefabricated house quality control.

Checklist: Check prefabricated house construction description point by point

• Mandatory contents according to Art. 249 EGBGB completely present.
• Expansion stage clearly named (turnkey, technikfertig, shell house for self-finishing).
• Wall structure, U-values, insulation thicknesses and energy standard specified.
• Heating, ventilation, sanitary and electrical with makes and quantities.
• Material selection budget per trade with price groups and quantities.
• All “bauseits” and “optional” positions listed and quantified.
• Binding information on the completion date included.
• Independent review by VPB, BSB or expert before signing.

Once the construction description is checked and the contract signed, control of the execution follows. How you recognize and document defects early you can read in the guide Prefabricated house defect inspection and - for a legally secure handover - under Prefabricated house final acceptance.