Precision
Profiles are roll-formed to controlled dimensions. Hole positions, lengths and labels come from the same manufacturing data as the drawings.
An open-book tiny house building system
One cabin. Fully engineered. Completely documented.
A precision-designed 6m building platform available as a trailer, structure, weatherproof shell or complete home. The physical product changes. The knowledge does not. Build it with us, or source every documented component through your regional catalogue.
- 6.0m
- core cabin
- 2.4m
- transport width
- 3,500kg
- trailer MAM
- 4
- delivery stages
Not a catalogue of houses.
A repeatable small-building platform that stays understandable for life.
01
The system
We do not design dozens of cabins. We keep improving one.
Every wall, fixing, service route and sheet cut is part of one controlled system. Repetition gives us something custom design rarely can: the time to test details, remove ambiguity, record decisions and improve the same product with every build.
Physical scope
Trailer → Structure → Shell → Home
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Knowledge supplied
The complete system at every stage
Buy the point where you want us to stop building. Receive the same permanent reference for construction, procurement, inspection, maintenance, repair, upgrades and future modification.
The decision filter
Every component has to earn its place.
- 01Structural strength
- 02Transportability
- 03Weight
- 04Longevity
- 05Serviceability
- 06Sustainability
- 07Cost
- 08Ease of construction
- 09Material availability
- 10Future maintenance
02
System anatomy
Nothing important is hidden behind the finished surface.
The cabin is organised as five coordinated layers. Each layer has its own drawing set, procurement schedule, installation sequence, inspection points and maintenance references.
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01
Transport base
Trailer, detachable platform, axle relationship, support points, floor cassette and road-spray protection.
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02
Primary structure
Numbered light steel floor, wall, roof, loft and structural partition members with controlled connections.
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03
Weather envelope
Sheathing, air and water control layers, insulation, thermal-bridge details, windows, doors and ventilated cladding.
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04
Services
Known electrical, plumbing, ventilation, heating, drainage and water routes kept accessible and recorded.
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05
Interior system
Repeatable wall lining, cabinetry, stairs, storage, seating and furniture built from documented parts.
Open specification
We publish the decision, not just the product name.
A specification is only useful when the owner understands why it exists. Each important component receives a decision record covering purpose, selected approach, alternatives, trade-offs, expected service conditions and maintenance.
System
Selected approach
Why
Trade-off and care
Primary frameStructure
Cold-formed galvanised light steel frame
Accurate, repeatable, lightweight, non-combustible and suitable for regional manufacture.
Higher thermal conductivity than timber. Requires deliberate thermal-break detailing and protection from persistent moisture.
External wallEnvelope
Screw-fixed thermally modified timber rainscreen over a vapour-open water-control layer
Renewable, dimensionally stable boards remain individually replaceable and can dry through the ventilated cavity.
Timber changes colour and needs planned inspection. Exposed boards can be left to weather evenly or refinished to the maintenance schedule.
InsulationThermal layer
High-recycled-content mineral wool within the frame and as a continuous external thermal-break layer
Non-combustible, vapour-open and durable; the continuous layer limits heat flow through the steel frame without relying on a foam-filled wall panel.
Heavier and thicker than some foams. Regional thickness is modelled for climate, condensation risk and the live mass budget.
RoofPrimary weather layer
Mechanically fixed, coated steel standing-seam roof over a ventilated build-up
Low mass, long service life and replaceable sheets suit transport vibration better than brittle or bonded finishes.
Rain noise and condensation need correct acoustic, ventilation and membrane details. Coating damage is inspected and repaired.
Floor undersideRoad exposure
Sealed, inspectable underside with protected junctions and documented penetrations
Road water and debris attack the floor differently from a conventional static building.
Damage cannot be ignored. The underside is checked after transport and during the annual inspection.
Interior joineryFit-out
FSC or PEFC plywood, screw-fixed modules and standard replaceable hardware with low-emission finishes
Efficient CNC cutting, durable exposed edges and repair without relying on a single cabinetmaker or bonded decorative system.
Sheet goods still carry embodied impacts. Product declarations, emissions, mass and wet-area protection remain part of approval.
This is one controlled construction system, not a finish menu. Exact brands, grades and region-specific thicknesses are published in the specification. Approved alternatives exist for continuity of supply, but any substitution must preserve thermal, moisture, fire, mass and service-life performance.
03
Light steel frame
Designed once. Manufactured locally.
The frame is not a proprietary black box. It is an engineered digital manufacturing package that approved LSF producers can turn into precut members, labelled kits or complete wall panels close to the project.
Repeatability
Straight members do not arrive with the variable moisture, twist or shrinkage that must be managed in site-cut timber.
Lower mass
A lighter primary structure protects more of the 3,500kg mass budget for insulation, services, furniture and useful payload.
Fast assembly
Numbered components, screw-fixed junctions and panel drawings turn a complex frame into a controlled sequence of small tasks.
Low waste
Precut members reduce site offcuts. Steel scrap remains readily recyclable through established material streams.
Regional supply
Customers are not locked to one factory. Approved local manufacturers work from the same profile, coating, gauge and quality specification.
01Engineering modelGeometry and load paths controlled
→
02Manufacturing fileMembers, holes, labels and panels
→
03Approved local producerMachine and quality checks verified
→
04Numbered frame kitReady for transport and assembly
Why not pretend LSF has no disadvantages?
Steel conducts heat readily, can corrode if water is trapped against it, and requires an accurate fixing strategy. The system addresses those weaknesses through thermal separation, condensation control, coating specification, protected cut edges, drainage and inspectable details. Those requirements are part of the manual, not left to site intuition.
04
Mass engineering
Weight is a design input, not a final surprise.
Conventional houses rarely need a live mass budget. A road-transportable cabin does. Every selected component is recorded by quantity and unit mass, then assigned to a location so the total and distribution can be reviewed before it reaches the trailer.
- Declared, calculated or measured component mass
- Running total by build stage and cabin zone
- Left-right and fore-aft distribution review
- Centre-of-gravity and axle relationship checks
- Allowance for water, gas, batteries, belongings and future changes
- Final weighbridge record added to the owner manual
Live mass ledger≤ 3,500kg MAM
Trailer and detachable platformVerified supplier data
Floor and primary structureCalculated from member schedule
Envelope and openingsQuantity × declared unit mass
Services and equipmentActual configured products
Interior and furnitureCNC sheet and hardware schedule
Operational payload allowanceReserved, not accidentally consumed
Final permitted towing, licence, axle and registration conditions depend on country, vehicle and completed configuration.
05
The knowledge layer
Not a plan set. A permanent operating reference.
Think less like a folder of house drawings and more like the technical library supplied with industrial equipment: structured, indexed, revision-controlled and useful at every stage of the product's life.
Download the sample documentation index ↓Engineering drawings
Floor, wall, roof and loft framing; structural sections; connection details; penetrations; support points and exploded assemblies.
Manufacturing package
Member schedules, profiles, gauge, coating, hole locations, panel drawings, fixing schedules, labelling and production checks.
Regional component catalogue
Exact quantities, current supplier prices, direct product links, price-check dates, availability, declared mass and controlled alternatives for the customer's region.
Cut lists
Steel, battens, cladding, insulation, plywood, cabinetry, trims and sheet optimisation references.
Construction manual
Tools, preparation, time and skill guidance, sequence, safety notes, common mistakes, tolerances and inspection checkpoints.
Services manual
Electrical, plumbing, ventilation, heating, drainage and water routes with access and isolation information.
Interior system
Wall lining, CNC cabinetry sheets, hardware, loft, stairs, bed, seating and storage construction.
Lifetime maintenance
Inspection intervals, cleaning, resealing, refinishing, servicing, replacement procedures and part references.
OH-06-GA-204REV A
Wall-to-floor connection
One reference language
The same identifier follows a part through its whole life.
- 1Specified in the engineering model
- 2Purchased or manufactured from the schedule
- 3Located in the assembly sequence
- 4Checked at the inspection point
- 5Found again for service or replacement
Construction manual
Each stage is written as a controlled build operation.
A good manual does not merely show the desired result. It tells the builder how to prepare, what can go wrong, what to measure and when work is ready to proceed.
Prepare
Required tools, parts confirmation, safe handling, substrate checks, weather limits and estimated team/time.
Assemble
Numbered order, fixing type, torque or spacing, tolerances, photographs and details at the point they are needed.
Inspect
Dimensions, level, plumb, sealing, continuity and concealed work checked before the next layer closes access.
Record
Actual products, substitutions, photographs, test results and sign-off added to the owner record.
Common mistakes are documented too.
Wrong fixingReversed membraneBlocked drainageUnsealed cut edgeMissing service access
Engineered interior
The fit-out is part of the product, not decoration added at the end.
Furniture, services and circulation compete for the same small volume and mass allowance. Designing them together produces a repeatable construction language that a local joiner, CNC workshop or capable owner can reproduce.
Wall systemsProfiles, service cavity, fixing centres, corners, trims and finish schedule.
CabinetrySheet layouts, cut lists, edge treatment, hinges, runners, handles and assembly order.
FurnitureLoft, bed, seating, storage and stairs coordinated with structure and services.
Healthy materialsFSC or PEFC timber, low-emission finishes and moisture-appropriate products selected within performance, longevity and weight limits.
Lifetime support
A cabin designed to be maintained for decades.
The owner's record changes with the building. Completed inspections, repairs, substitutions and upgrades are added to the same system so a future owner or technician can understand what was built and what changed.
After transportInspect
Chassis, underside, fixings, seals, openings and service connections.
AnnualMaintain
Cladding, drainage paths, sealants, ventilation, plumbing and electrical checks.
As requiredRepair
Find the part reference, approved replacement and documented removal sequence.
FutureUpgrade
Review structure, services and mass before changing equipment or interior modules.
Build your own
We price every component. We do not invent a misleading DIY total.
Customers receive a complete regional catalogue for the same cabin we supply. It turns every drawing reference into a sourceable item, using suppliers and current pricing relevant to the build location.
You buy components directly from the listed suppliers and control the timing, delivery and labour. Your build cost is the sum of the products you select, regional taxes and delivery, plus the labour and tools you arrange. OpenHouse does not publish a fixed build-your-own package price because those variables are not ours to guarantee.
RegionPortugal or United KingdomLocal currency, VAT basis, delivery area and stock context
Exact productSpecification and direct linkManufacturer code, dimensions, quantity and declared mass
Current priceSupplier price and check datePack price, unit rate, estimated stage cost and availability
ContinuityApproved alternativeOnly where performance and weight remain within the engineering rules
Part
Specified component
Qty / mass
Regional supplier
Price record
ENV-214Thermal layer
Rigid mineral wool, specified density and thickness
m² schedule
kg total shown
kg total shown
Direct product link ↗Stock and delivery area
Live customer priceChecked date shown
ENV-326Rainscreen
Thermally modified timber, profile and grade fixed
Linear-metre schedule
Waste factor shown
Waste factor shown
Direct product link ↗Approved local merchant
Live customer pricePack and unit rate
FIX-118Cladding fixing
A4 stainless screw, head and length specified
Box count
Installed mass shown
Installed mass shown
Direct product link ↗Second source recorded
Live customer priceAvailability shown
Catalogue access is included for customers at every delivery stage. Prices are supplier snapshots, not OpenHouse quotations; the supplier's checkout price, tax, stock and delivery terms apply.
06
Four delivery stages
Choose how much building work you want us to complete.
These are not four different houses. They are four stopping points in the same cabin system. Every stage includes the complete documentation library, owner record structure and regional component catalogue. The prices below are for OpenHouse-supplied packages, not build-your-own material totals.
Indicative premium package pricing in euros, excluding VAT, delivery, jacks, site works and country-specific registration or approval costs. Build-your-own customers see item-level regional supplier pricing in their catalogue instead.
01
Delivery stage
Trailer
The road-conscious starting point: a Vlemmix 3,500kg trailer, detachable 6m platform and a waterproof insulated floor cassette engineered around transport exposure and the cabin's live mass budget.
- 2.4m transport width and 6m core platform
- Durable sealed underside with inspectable penetrations
- Detachable supports, fixing plan and weight ledger
- Documentation and regional component catalogue included
Starting from€10,950Trailer and detachable platform. Platform-only supply from €3,500.
02
Delivery stage
Structure
Add the complete galvanised light steel floor, wall, roof, loft and partition structure, locally roll-formed from OpenHouse manufacturing data for accurate dry assembly.
- Precut, pre-punched and labelled structural members
- Regional manufacture with controlled profile, gauge and coating
- Screw-fixed assembly sequence, tolerances and hold points
- Low site waste, recyclable steel and no timber shrinkage
Starting from€17,500Trailer stage plus locally manufactured, numbered LSF structure.
03
Delivery stage
Shell
Add one durable, vapour-open envelope system: structural sheathing, mineral insulation, continuous thermal separation, membranes, ventilated cladding, coated steel roof and high-performance openings.
- High-recycled-content mineral insulation
- Replaceable thermally modified timber rainscreen
- Mechanically fixed coated steel roof
- Documented first-fix electrical and plumbing routes
Starting from€31,500Structure stage plus the complete high-performance shell, openings and service routes.
04
Delivery stage
Complete Home
Add the coordinated interior, services, equipment, testing and handover record. The fit-out uses low-emission timber products, repairable modules and standard hardware rather than bonded decorative systems.
- FSC or PEFC plywood cabinetry and furniture
- Bathroom, kitchen, efficient lighting and appliances
- Accessible services, ventilation and commissioning
- Replacement references and lifetime maintenance record
Starting from€49,500Shell stage plus fitted premium interior, equipment, commissioning and handover.
Scope comparison
The build scope grows. The knowledge stays complete.
Included
Trailer
Structure
Shell
Home
Trailer + detachable platform
✓
✓
✓
✓
LSF primary structure
—
✓
✓
✓
Weather envelope + openings
—
—
✓
✓
First-fix services
—
—
✓
✓
Interior, equipment + commissioning
—
—
—
✓
Complete engineering + manufacturing library
✓
✓
✓
✓
Regional component prices + direct supplier links
✓
✓
✓
✓
Procurement, cut lists + construction manual
✓
✓
✓
✓
Services, interior + lifetime maintenance manuals
✓
✓
✓
✓
Complete Home · One configuration
A finished interior built from reproducible parts.
These images show one proposed fit-out. Window positions, finishes and equipment can be configured only where the engineering, services and mass budget allow.
Full-height glazing brings daylight deep into the 6m plan and creates a direct relationship with the site.
Seating, storage, stairs, loft and desk share one coordinated joinery and hardware language.
Cabinet parts, hardware, service penetrations and worktop cuts are defined before fitting begins.
Wet-area surfaces and accessible service routes are selected for cleaning, inspection and future repair.
Structure, rooflight, ventilation, lighting and low storage are resolved as one compact assembly.
Configure a supplied package
Choose the base. Then choose where our physical supply stops.
This calculator covers OpenHouse-supplied packages. Changing stage replaces your previous selection; it never adds a second cabin. For a build-your-own project, your customer catalogue provides component-level supplier pricing instead of a fixed total.
The longer view
This cabin is version one of a shared building platform.
Future cabins can change in size and use while retaining the same component logic, documentation style, hardware families, manufacturing controls and maintenance philosophy. The objective is not a series of unrelated houses. It is a housing platform that becomes more useful with every version.
Construction languageComponent standardsDocumentation systemHardware familiesMaintenance philosophyManufacturing process
Regional launch
One engineering standard. Local supply and support.
Portugal
Regional specification, euro component catalogue, direct local supplier links, approved LSF manufacture and partner assembly beginning in Central Portugal.
United Kingdom
Region-appropriate envelope specification, sterling component catalogue and direct supplier links for owners, workshops and approved installers.
Use and registration
This is a road-transportable building system. Planning, site use, towing and road registration depend on country, site, vehicle and intended use. Guidance is not legal approval.
Technical enquiry
Tell us what you want to build and where.
We will respond with the relevant regional specification, catalogue access route, current supplied-package lead time and next technical questions.
Download documentation sample ↓