There is no universal inclusion list for "turnkey" or "shell" homes across Europe, so every manufacturer draws the lines differently. This guide pins the three finish levels down with component-by-component tables: shell (weathertight structure, no systems), semi-finished (complete envelope plus installed or roughed-in systems, unfinished interior surfaces), and turnkey (move-in ready). On the BIOBUILDS list, turnkey adds €20,000-€120,000 over semi-finished, depending on model.
Two houses can both be sold as "turnkey" and differ by a kitchen, all the flooring, and every light fixture. The finish level names are marketing labels; only the inclusion list behind them is a product. This guide answers one question: what does each finish level contain, so you can put any two offers side by side and compare the same thing.
The neighboring questions live in their own guides: what the house itself costs, what the site and permits add on top, and how the purchase process and contract work. BIOBUILDS, the European manufacturer publishing this guide, sells two of the three levels, semi-finished and turnkey, and publishes the full inclusion list for both; those lists anchor the tables below.
What do shell, semi-finished, and turnkey include?
European offers commonly fall into three broad tiers under different names. German manufacturers sell Rohbau, ausbaufertig, and schlüsselfertig; Romanian builders quote la roșu, la gri, and la cheie. The tiers translate, the inclusion lists do not, which is why the definitions below are stated as component lists rather than labels:
- Shell: the load-bearing structure, roof, and usually windows; weathertight and nothing more. No electrical, no plumbing, no interior surfaces. Whether insulation and cladding are included varies by offer, so a shell quote must be read line by line.
- Semi-finished: the fully finished exterior plus every technical system installed or roughed in. What remains is interior surface work: paint, wall panels, flooring, fixture covers.
- Turnkey: the finished home. Interior surfaces, bathroom, doors, and lighting complete; you receive keys and move in. Some manufacturers include kitchen cabinetry, while others leave it to the buyer, which is exactly why the inclusion list has to be read.
Here is the full comparison, component by component. The shell column describes the market category; the other two columns are the published BIOBUILDS inclusion lists:
| Component | Shell | Semi-finished | Turnkey |
|---|---|---|---|
| Structure (35 cm C24 timber-frame walls) | Yes | Yes | Yes |
| STEICO insulation + airtight membrane system | Varies by offer | Yes | Yes |
| Exterior cladding (Yakisugi or Lunawood) | Varies by offer | Yes | Yes |
| Low-slope EPDM roof, integrated gutters | Yes (weathertight) | Yes | Yes |
| Triple-glazed windows, Genesis 90 frames | Usually | Yes | Yes |
| Electrical (panel, wiring, outlet boxes) | No | Roughed-in | Finished, with switches and covers |
| Plumbing (in-wall, concealed cistern) | No | Roughed-in, bathroom waterproofed | Finished, all fixtures installed |
| Ventilation and heating (Zehnder MVHR + heat pump) | No | Ducting prepared; unit is a per-model upgrade (€4,800-€18,800) | Included |
| Interior walls and ceiling | No | Sanded OSB, ready to finish | Finished (wood slats, felt, or veneer) |
| Flooring | No | No | Triple-layer parquet |
| Bathroom fittings (shower, basin, WC) | No | No | Yes |
| Kitchen installations, ready for cabinetry and appliances | No | Yes | Yes |
| Interior doors and lighting | No | No | Yes |
Compare inclusion lists, never level names. A "turnkey" offer without a kitchen and an "ausbaufertig" offer with installed ventilation are both common; the label tells you nothing a table like the one above doesn't verify.
Semi-finished: the complete envelope, your surfaces
Semi-finished is not a shell with insulation. Everything that requires factory precision, certification, or a licensed trade arrives finished or roughed in:
- Complete structural system: 35 cm C24 FSC-certified timber-frame walls
- Full STEICO wood-fiber insulation and airtight membrane system, zero thermal bridges
- Exterior cladding: Yakisugi charred timber or Lunawood thermowood
- Triple-glazed windows (U-value 0.50) with Passivhaus-certified Genesis 90 frames, installed
- Low-slope EPDM roof with up to 300 kg/m² load capacity, vs around 80 kg/m² standard
- Ventilation ducting prepared for the Zehnder MVHR system (the MVHR + heat pump package itself is a per-model configurator upgrade, €4,800-€18,800)
- Electrical panel, wiring, and sealed outlet boxes to EU standards
- In-wall plumbing with Grohe concealed cistern; bathroom fully waterproofed
- Kitchen installations prepared in position, ready for your cabinetry and appliances
- Interior surfaces in Passive House-approved, formaldehyde-free sanded OSB, ready for direct finishing
The remaining work is surface finishing, and it is deliberately engineered to be simple. The OSB interior accepts finishes directly, so there is no drywall phase and no construction dust:
Together, these are hours of simple work rather than weeks of construction. You can do them yourself or hire installers. The full specification is on the semi-finished page.
Turnkey: what the premium buys
A turnkey BIOBUILDS home contains everything in the semi-finished list, then completes the interior with the factory's own finish package:
- Ceiling: natural wood slats mounted on acoustic felt.
- Walls: sound-absorbing vegan felt or real-wood veneer in Oak, Walnut, or Ebony tones.
- Floor: triple-layer parquet with a real-wood top layer, in Cashmere or Hazelnut.
- Bathroom: floor-to-ceiling marble-composite panels, French-designed walk-in shower, German Grohe fixtures, Italian slim-profile composite basin, and a wall-hung Grohe WC with concealed tank (the 24 m² Nest uses a Geberit glass tank).
- Electrical and plumbing, finished: switches, covers, and outlets installed; every bathroom fixture connected.
- Ventilation and heating, installed: the Zehnder MVHR unit with Samsung WindFree heat pump, the same package that is a paid per-model upgrade on semi-finished.
- Interior doors and lighting throughout.
The kitchen arrives the same way at both levels: installations fully prepared in position, with cabinetry and appliances left as your own choice. Factory production takes about 3 weeks at either finish level; the difference is the interior work after installation. Turnkey arrives with its interior finish package complete, while semi-finished leaves the three surface steps above to you. The complete finish specification is on the turnkey page.
How big is the price difference between the levels?
The current list prices, net of VAT, DAP delivery with all-risks cargo insurance included:
| Model | Semi-finished | Turnkey | Turnkey premium |
|---|---|---|---|
| Nest, 24 m² | from €39,800 | from €59,800 | €20,000 (+50%) |
| Wanderlust, 48 m² | from €59,800 | from €109,800 | €50,000 (+84%) |
| Serenity, 95 m² | from €109,800 | from €189,800 | €80,000 (+73%) |
| Sanctuary, 142 m² | from €159,800 | from €279,800 | €120,000 (+75%) |
The premium is concentrated in the bathroom, the floor and wall finishes, and the ventilation and heating package. For a full price analysis by model and square meter, including a comparison with the wider market, see the prefab price guide.
Semi-finished fits you if: you can handle simple surface finishing, you want to choose your own colors, panels, and parquet, or you would rather put €20,000-€120,000 into land, furniture, or premium materials than into finishing labor.
Semi-finished works against you if: you need the interior complete when the home is installed, your lender requires a completed dwelling at handover, or the home must generate income from week one. In those cases, the turnkey premium pays for a completed interior.
BIOBUILDS stops at semi-finished
In the certified segment, the shell level stops making sense. The energy performance comes from the envelope working as one engineered system: insulation, membranes, airtight taping, windows, and ventilation, tested together to the Passivhaus airtightness limit of 0.6 air changes per hour, with an internal target of 0.4. That airtightness is built and verified in the factory. A shell handed over without its systems leaves critical parts to be completed on site and no longer matches the complete tested system.
Semi-finished is therefore the lowest level we sell: the complete Passivhaus-certified envelope arrives factory-built and sealed, and everything left to you (paint, panels, and parquet) bonds onto the OSB surface without penetrating the airtight layer. With the MVHR package in place, heating demand stays around 15 kWh/m² per year because the interior finishing does not alter the tested envelope. The package is included with turnkey and is available as a per-model configurator upgrade for semi-finished homes.
Both finish levels carry the same coverage: a 5-year structural warranty plus a 24-month legal warranty (12 months for commercial use), with component manufacturers' warranties on top. In a semi-finished home, the finishes you install yourself are covered by their own material warranties instead.
