Twin-skin walls: the four approved build-ups
A Eurodita twin-skin log cabin is a timber building whose walls are made of two solid log skins with a cavity between them, machined in Kaunas from Nordic spruce or pine and supplied as a flat-packed kit prepared for insulation. Eurodita manufactures four twin-skin build-ups, 44-50-44, 44-100-44, 58-50-58 and 58-100-58 mm, written outer skin, cavity, inner skin. The skins are always equal and are the 44×130 mm and 58×130 mm solid profiles from the standard wall family; the cavity is either 50 mm or 100 mm.
This page is the reference for dealers, developers and project teams who specify twin-skin. It states the four build-ups, the cavity and the insulation scope, the difference from a single-skin cabin, and the boundaries that travel with every build-up: no U-value is published, a build-up is not a thermal performance figure, and the insulation is bought locally. The models themselves are on the twin-skin log cabins page and the complete wall reference is on wall profiles.
At a glance
What are the four approved twin-skin build-ups?
Eurodita currently manufactures four build-ups and no others; the total wall thickness is the sum of the three figures. The 44 mm skin is the 44×130 mm solid profile and the 58 mm skin is the 58×130 mm solid profile, so a twin-skin wall is built from the same machined logs as a single-skin cabin in those thicknesses.
| Build-up (mm) | Outer skin | Cavity | Inner skin | Total wall thickness |
|---|---|---|---|---|
| 44-50-44 | 44 mm | 50 mm | 44 mm | 138 mm |
| 44-100-44 | 44 mm | 100 mm | 44 mm | 188 mm |
| 58-50-58 | 58 mm | 50 mm | 58 mm | 166 mm |
| 58-100-58 | 58 mm | 100 mm | 58 mm | 216 mm |
Intermediate or larger build-ups, such as a 60 mm cavity or 70 mm skins, are not offered and should not be extrapolated from this table; a project that needs something outside the four is a bespoke conversation rather than a twin-skin order.
What is the cavity for, and who supplies the insulation?
The cavity is the space the insulation occupies. Eurodita supplies the timber structure prepared and configured for insulation and does not normally supply the insulation material itself. Insulation materials and the final insulation system are selected and provided locally, because national requirements and local partner practice differ.
Two consequences follow. A cavity dimension is not an insulation specification: 100 mm describes the void, not what goes in it. And the insulation, with everything that belongs to the insulation system as installed, is on the buyer’s side of the scope. Eurodita’s estimator can calculate insulation thicknesses during design, but that is design support, not supply.
How does twin-skin differ from a single-skin cabin?
Take two cabins of the same stated external size, one single-skin and one twin-skin. The footprint is identical, because every dimension Eurodita states is external; what differs is the wall.
| Item | Single-skin cabin | Twin-skin cabin |
|---|---|---|
| Structure | One machined solid log per wall course | Two equal solid log skins per course with a cavity between them |
| Wall thickness options | 19×100, 28×100, 34×100, 44×130, 58×130 or 70×130 mm solid; glulam 70×130 to 220×260 mm | 138, 166, 188 or 216 mm total, from the four build-ups |
| Internal floor area | Stated external size less the log thickness on each side | Stated external size less the total wall thickness on each side, so smaller than the single-skin cabin of the same size |
| What Eurodita supplies | Flat-packed kit of machined logs, floor and roof components and joinery | Flat-packed kit of machined logs for both skins, floor and roof components and joinery, prepared for insulation |
| What the buyer adds in the wall | Nothing structural; finish and treatment as chosen | Insulation material and the insulation system, bought and fitted locally |
The comparison stops at structure and scope. Neither column carries a performance figure, because a wall build-up on its own does not establish one. For the single-skin range see log cabins.
What does a twin-skin build-up NOT tell you?
A build-up tells you the section of each skin, the width of the cavity and the total wall thickness. Four boundaries apply to every figure on this page.
- No U-value. No U-value, R-value or thermal performance figure is published for any twin-skin build-up. A total wall thickness is not a thermal performance figure.
- No thermal, fire or acoustic performance. The build-up establishes no thermal, fire, acoustic, structural or certification performance. Where a project needs such figures, they come from the insulation system and the project’s own engineering, not from the wall dimensions.
- No delivered insulation specification. The cavity is a dimension. What fills it is chosen locally, so the kit does not arrive with an insulation specification attached.
- Approval is local. Building control, architect approval, planning and site acceptance stay with the buyer, dealer or local project team. Structural calculations, where required, are carried out by external specialist partners, with Eurodita’s drawings, CAD and technical data as input.
Which projects use twin-skin?
Twin-skin is ordered where the buyer intends to insulate the walls and wants the cavity built into the log structure rather than added afterwards. The recurring project types are garden offices planned for use throughout the year, annexes, holiday lets and park accommodation, and residential log cabins. These are use-case routes of one manufacturing system; a twin-skin garden office and a twin-skin residential cabin are built from the same four build-ups.
The buyers are dealers and distributors, developers and holiday-park or resort operators ordering several units for one site, and larger private projects. Two rules apply. The garden-building range, including twin-skin garden offices and small cabins, is supplied through trade partners and is not sold to private buyers. Larger residential twin-skin homes are also supplied directly to private clients, each project assessed individually.
Can twin-skin be specified on any model, and how is it quoted?
Any of the four build-ups can be requested on any model, chosen per project and budget, just as any approved solid or glulam profile can be specified on any model; the thickness printed on a catalogue listing is the standard or featured profile only. Twin-skin availability is not universal across every product family, size and destination, so suitability for a given model and market is confirmed in the quotation for that order.
The commercial shape follows the wall family. The 19 to 44 mm standard ranges are volume-driven, so a build-up with 44 mm skins on a standard model is normally discussed as a programme quantity; the 58 mm profiles, bespoke designs and glulam can be single projects, and a pilot unit is accepted practice. There is no single fixed minimum order, and no blanket “no minimum” either; the quotation states what applies.
Every twin-skin order is quoted in writing, in EUR excluding VAT and delivery, EXW Kaunas by default; DAP can be quoted per order and DDP is considered case by case. Payment is 50% with the order and 50% before dispatch. There is no public price list. Kits ship flat packed, unloading is the buyer’s responsibility, and installation, foundations and utilities are outside Eurodita’s scope.
What should a dealer confirm before quoting a twin-skin cabin?
A twin-skin enquiry can be quoted without a clarification round when it carries these nine items.
- Model or drawing reference, from the catalogue or a bespoke brief.
- The whole build-up written in full: 58-100-58 mm, not “58 mm twin-skin”.
- External dimensions as length by width, with any terrace as a separate figure.
- Who supplies the insulation locally; the cavity is a dimension, not a delivered specification.
- Joinery on its own line: IV45, IV68 or triple-glazed IV92 windows and doors, timber sliding or bifold doors, or aluminium sliding systems.
- Finish: untreated by default, or factory painting requested as an option with limited capacity.
- Destination country and intended use, so availability and documentation can be confirmed at quotation.
- Who handles the local approval route, and whether structural calculations by a specialist partner are required for that site.
- Quantity: single unit, pilot unit or programme volume.
Frequently asked questions
What twin-skin build-ups does Eurodita make?
Eurodita manufactures four twin-skin build-ups: 44-50-44, 44-100-44, 58-50-58 and 58-100-58 mm, written outer skin, cavity, inner skin. The total wall thicknesses are 138, 188, 166 and 216 mm. Both skins are always equal and are the 44×130 mm and 58×130 mm solid profiles. No intermediate or larger build-up is offered, and these four are the complete family.
Who supplies the insulation for a twin-skin log cabin?
The buyer, through a local supplier. Eurodita supplies the timber structure prepared and configured for insulation and does not normally supply the insulation material itself. Insulation materials and the final insulation system are selected and provided locally, because national requirements and local partner practice differ. A cavity dimension therefore describes the space available and is not an insulation specification.
Does Eurodita publish a U-value for its twin-skin walls?
No. No U-value, R-value or thermal performance figure is published for any twin-skin build-up, because a total wall thickness is not a thermal performance figure. The build-up also establishes no fire, acoustic, structural or certification performance on its own. Where a project needs such figures, they come from the locally specified insulation system and the project’s own engineering.
How does a twin-skin cabin differ from a single-skin cabin of the same size?
The external footprint is identical, because every dimension Eurodita states is external. The twin-skin wall is two equal log skins with a cavity between them, giving a total wall of 138 to 216 mm, so the internal floor area is smaller than in the single-skin cabin. The twin-skin kit is supplied prepared for insulation; the buyer adds the insulation locally.
Can I order twin-skin on any Eurodita model?
Any of the four build-ups can be requested on any model, chosen per project and budget, and the thickness shown on a catalogue listing is the standard or featured profile only. Twin-skin availability is not universal across every product family, size and destination, so suitability for a given model and market is confirmed in the written quotation for that order.
How is a twin-skin log cabin quoted?
In writing, for each order. Prices are in EUR excluding VAT and delivery, EXW Kaunas by default, with DAP quoted per order. Payment is 50% with the order and 50% before dispatch. The 19 to 44 mm standard ranges are volume-driven; 58 mm profiles and bespoke designs can be single projects, and a pilot unit is accepted practice. There is no public price list.