Non-negotiable cost caps

These are stated openly and held by design. If a build exceeds these numbers, the system has been assembled incorrectly, or the component specification has been violated.

1 The structural shell never costs more than €20,000 in materials for a 70-84m² home.
2 The complete materials cost never exceeds €50,000.
3 If labour is hired, it never exceeds €25,000. In a self-build, labour is free.

Why these numbers are achievable. The conventional construction industry charges what the market will bear. A €150,000 house contains perhaps €35,000 in materials. The remainder is labour markup, contractor overhead, architect fees, project management, financing costs, and profit margin at every layer. Hestia removes every layer between the materials and the occupant. The family buys the materials directly, follows the protocol, and builds. The only remaining costs are the materials themselves, a short engagement with a structural engineer for stamp approval, and whatever professional services the owner chooses to hire rather than do themselves.

€18,100 - €25,400 in materials

This is the weathertight structure: walls, roof, floor, foundation, windows, and doors. Everything that keeps wind and rain out. Nothing that makes it comfortable to live in yet. No concrete. No rebar. The house is over-engineered, but the cost is minimal.

Item Quantity Unit € Total € Notes
EPAL Euro Pallets 90 €10 €900 Logistics depot, any EU country
OSB3 Sheets (2500x1250x15) 32 €14 €448 Builders merchant
I-Joists (240mm x 5m) 24 €21 €504 Timber merchant, cut to length
Helical Ground Screws 16 €40 €640 Specialist supplier, installed
Sill Beam Timber 30m €8/m €240 Treated softwood, builders merchant
Ring Shank Nails (3.1x90) 3,000 €0.04 €120 Hardware store
PU Adhesive (EN 204 D4) 15 tubes €8 €120 Builders merchant
Breather Membrane 2 rolls €55 €110 Builders merchant
Roofing Steel Sheets 45m² €12/m² €540 Metal merchant, cut to length
Roof Battens 60m €3/m €180 Treated softwood
Double Glazed Windows 4 €350 €1,400 Standard sizes, local supplier
External Door + Frame 1 €450 €450 Steel or timber, local supplier
M12 Bolts + Washers 100 €1.50 €150 Hardware store
Joist Hangers 48 €4 €192 Simpson or generic, hardware store
Timber Cladding (exterior) 65m² €15/m² €975 Treated softwood, local merchant
External Paint / Stain 20L €25/L €500 Breathable, timber merchant
Guttering + Downpipes 25m €12/m €300 Plastic or aluminium, hardware store
Floor Decking (OSB3) 12 sheets €14 €168 Same as wall OSB
Floor Insulation (below) 38m² €12/m² €456 Rock wool or EPS, builders merchant
Damp Proof Membrane 1 roll €180 €180 Under floor, builders merchant
Butyl Tape + Sealants assorted - €200 Hardware store
STRUCTURAL SHELL TOTAL - - €18,100 - €25,400 Range depends on window/door spec and cladding choice

€9,100 - €13,300

Everything that makes the home function without grid connection. These are optional in a grid-connected build, but they are included in the complete home price because the Hestia system is designed for genuine off-grid capability.

Item Spec Total €
Solar PV (3kW) + Battery (10kWh) Panels, inverter, lithium battery €4,000 - €5,500
Solar Hot Water Evacuated tube collector, 200L tank €1,500 - €1,800
Composting Toilets 2x separating dry toilets €1,700 - €1,900
Water System Rainwater collection OR mains connection €1,500 - €3,500
Smart Home Sensors Shelly modules, WiFi, open firmware €400
OFF-GRID TOTAL - €9,100 - €13,300

€1,300 - €3,950

Short, premium engagements with licensed professionals. Not a project manager for six months. A structural engineer for a week. An electrician for a day.

Service Scope Cost €
Structural Engineer Calculations + stamp for building permit up to €2,000
Blown Rock Wool Contractor Supply + install, 2-3 hours on site €800 - €1,200
Electrician Consult + sign-off on first-fix €300 - €450
Plumber Wet wall + connection sign-off €200 - €300
PROFESSIONAL TOTAL - €1,300 - €3,950

€600 - €3,800

Item Cost € Notes
Permit + Legal up to €3,000 Varies enormously by municipality
Tools (nail gun + saw, purchased) €200 - €400 Can be rented for ~€50
Transportation €400 One truck delivery, 50km average
ONE-OFF TOTAL €600 - €3,800 -

Contingency

15% of total materials cost = approximately €4,400 - €6,800. This covers waste, price variation, mistakes, and the inevitable item you forgot.

Shell materials€18,100 - €25,400
Off-grid package€9,100 - €13,300
Professional services€1,300 - €3,950
One-off costs€600 - €3,800
Contingency (15%)€4,400 - €6,800
TOTAL COMPLETE HOME~€50,000

The self-build labour advantage. In a conventional build, labour is 50-70% of total cost. In a Hestia self-build, labour is €0. The family, their friends, and their community do the work. The protocol is the skill transfer. One person who has built a Hestia home can teach ten people to build the next. The knowledge compounds.

If labour must be hired (elderly occupants, disability, time constraints), it is capped at €25,000. This is approximately 300 hours at €80/hour, roughly the time required for assembly and finishing by a small crew.

How Hestia compares to market prices

Build Type Cost per m² 84m² Total Time to Occupation
Typical EU new build (contractor) €2,500 - €4,000 €210,000 - €336,000 12-18 months
Prefab modular home (factory) €1,800 - €2,800 €151,000 - €235,000 6-12 months + lead time
Self-build timber frame (conventional) €1,200 - €1,800 €100,000 - €151,000 12-18 months
Hestia (self-build) €595/m² ~€50,000 3-6 months
€2,500-4,000
Typical EU cost/m²
€595
Hestia cost/m²
=
~10x
Roughly one-tenth of market price

A single parent on a median salary, with €15,000 saved and a €30,000 loan, can afford a three-bedroom home. The total materials cost for a complete 84 square metre family home stays under €50,000. It is our job to make that enough. It is our job to make the numbers work. This is not charity. This is not subsidy. This is structural affordability, achieved by removing the intermediation that inflates cost, and by publishing the knowledge that enclosure has kept expensive.