There is no universal inclusion list for "turnkey" or "shell" homes across Europe, so every manufacturer draws the lines differently. This guide compares shell (structure and roof, with windows and weatherproofing defined by the offer), semi-finished (complete envelope, selected installations and unfinished interior surfaces), and turnkey (finished interior). BioBuilds offers Exterior Finished and Turnkey; the latter adds €55,930–€209,440, 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 use terms such as shell, semi-finished, and turnkey. German Rohbau and Romanian la roșu do not necessarily mean a weathertight shell; windows and roof coverings may be excluded. The definitions below identify what to check in each offer:
- Shell: the load-bearing structure and roof structure. Windows, roof coverings, insulation, and cladding vary by supplier. Interior installations and finishes should not be assumed.
- Semi-finished: the envelope is complete, while the extent of technical installations and interior work varies. Systems may be installed, roughed in, or optional. BioBuilds calls its version Exterior Finished; the table below separates standard scope from upgrades.
- 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:
Exterior Finished has a fully finished exterior. Electrical cables and conduits are factory-installed and included as standard. Plumbing and electrical panel installation are separately priced upgrades, preselected and included in the starting price; either can be removed. Ventilation equipment, ducts and installation form one optional upgrade. Turnkey includes all three installations. Bathroom waterproofing remains standard without plumbing.
| Component | Shell | Exterior Finished | Turnkey |
|---|---|---|---|
| Load-bearing structure | Yes | 35 cm C24 timber-frame walls | 35 cm C24 timber-frame walls |
| STEICO insulation + airtight membrane system | Varies by offer | Yes | Yes |
| Exterior cladding (Yakisugi or Lunawood) | Varies by offer | Yes | Yes |
| Roof | Scope varies by offer | Low-slope EPDM roof, integrated gutters | Low-slope EPDM roof, integrated gutters |
| Windows | Scope varies by offer | Triple glazing, Genesis 90 frames | Triple glazing, Genesis 90 frames |
| Electrical cables and conduits | No | Included as standard | Installed, with switches and covers |
| Electrical panel installation | No | Removable upgrade | Included |
| Plumbing (in-wall, concealed cistern) | No | Removable upgrade; waterproofing stays standard | Finished, all fixtures installed |
| Ventilation and heating (Zehnder MVHR + heat pump) | No | Ventilation equipment, ducts and installation: optional package, €9,520–€29,155 | Included |
| Interior walls and ceiling | No | Smooth 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 | With plumbing; electrical cables and conduits are standard | 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
Exterior Finished provides the complete exterior, with installations selected separately:
- 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 (glazing Ug = 0.50 W/m²K) 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 equipment, ducts and installation: optional package, €9,520–€29,155
- Electrical cables and conduits: factory-installed, included as standard
- Electrical panel installation: removable upgrade
- In-wall plumbing: removable upgrade; bathroom waterproofing stays standard
- Kitchen water connections prepared with plumbing; electrical cables and conduits are standard
- Interior surfaces in Passive House-approved smooth OSB made with formaldehyde-free adhesives, ready for direct finishing
Alongside the installations you choose, the remaining work includes surface finishing. 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.
- 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.
Turnkey includes prepared kitchen installations. Exterior Finished includes the electrical wiring as standard and requires the plumbing upgrade for kitchen water connections. Cabinetry and appliances remain 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. With BioBuilds Exterior Finished, the remaining work also includes bathroom fittings, interior doors, lighting, final sockets and switches, any unselected installations, and site connections. The complete finish specification is on the turnkey page.
How big is the price difference between the levels?
The table shows current list prices including an illustrative 19% German VAT. Transport is quoted separately by destination; Irish storefront prices include transport.
| Model | Exterior Finished | Turnkey | Turnkey premium |
|---|---|---|---|
| Wanderlust, 48 m² | from €78,540 | from €134,470 | €55,930 (+71%) |
| Serenity, 95 m² | from €138,040 | from €247,520 | €109,480 (+79%) |
| Sanctuary, 142 m² | from €198,730 | from €358,190 | €159,460 (+80%) |
| Bloom, 190 m² | from €248,710 | from €458,150 | €209,440 (+84%) |
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.
Exterior Finished fits you if: you want to choose your own colors, panels, and parquet and can do the surface work yourself or hire installers. Allow for materials, fixtures, labor and any upgrades outside the starting package when comparing the total with Turnkey.
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.
Why BioBuilds starts with Exterior Finished
BioBuilds sells Exterior Finished and Turnkey on the same Passivhaus-certified building system. The factory-built envelope includes the structure, insulation, airtight layers and windows. Passivhaus airtightness is assessed by a blower-door test at 50 Pa, with a limit of 0.6 air changes per hour; BioBuilds reports an average of around 0.4 on completed homes.
Interior surface finishes can be applied to the OSB without penetrating the airtight layer. Exterior Finished still requires the fixtures and installations identified above. The Zehnder MVHR and heat-pump package is included with Turnkey and optional with Exterior Finished. BioBuilds' building system is designed for the Passivhaus heating-demand limit of 15 kWh/m² per year; actual demand depends on climate, orientation, shading, configuration and use.
Both finish levels carry the same coverage: a 5-year structural guarantee, in addition to your statutory defect rights, with component manufacturers' warranties on top. In a semi-finished home, the finishes you install yourself are covered by their own material warranties instead.
