Technologie Ossature Acier Léger (LGSF)

Metallurgy & Durability

The Science of Structural Cold-Formed Steel

Light Gauge Steel Framing (LGSF) combines the unmatched tensile strength of structural steel with automated CNC precision, creating buildings that outlast conventional concrete and timber structures.

S350GD Grade Steel

350 MPa

High-tensile structural steel certified to EN 10346 with guaranteed yield strength exceeding 350 N/mm² for maximum structural load capacity.

Z275 Galvanization

275 g/m²

Continuous hot-dip zinc coating (20 microns per side) protecting steel framing against oxidation, rust, and salt air for 100+ years.

CNC Precision

±0.5 mm

Fully automated roll-forming lines produce profiles with sub-millimeter tolerances, pre-punched service holes, and dimpled screw locators.

Seismic Ductility

PGA ≥ 0.40g

Light structural mass combined with high ductility absorbs and dissipates ground energy, certified for high seismic zones (Eurocode 8).

Material Metallurgy

High-Tensile S350GD Galvanized Structural Coils

Unlike traditional wood framing that twists, rots, and swells with moisture, cold-formed steel is 100% dimensionally inert. Every profile is roll-formed from certified EN 10346 structural coil steel with S350GD yield performance.

The continuous hot-dip zinc coating (Z275 — 275 g/m² combined zinc layer) creates a self-healing cathodic protection barrier against coastal humidity, industrial atmosphere, and corrosive environmental exposure for well over a century.

100+ Year Durability EN 10346 Certified 100% Termite & Rot Proof

S350GD+Z275 Structural Steel Framing & Automated Precision

Envelope Engineering

Multi-Layer High-Performance Wall Anatomy

A cross-section breakdown of our exterior wall system engineered to eliminate thermal bridging, prevent moisture condensation, and deliver Passivhaus-level thermal efficiency.

1

Architectural Exterior Cladding

Composite wood (WPC), fiber cement siding, porcelain panels, standing seam zinc, or mineral acrylic render.

2

Ventilated Drainage Cavity & Timber/Steel Battens

25-38mm vertical ventilated air space for continuous drainage, vapor evacuation, and solar heat dissipation.

3

Continuous External Thermal Break (EIFS / ETICS)

50-100mm high-density external rockwool or graphite EPS layer wrapping all steel studs to eliminate thermal bridges.

4

Structural Sheathing (OSB-3 / BoardeX / Fiber Cement)

12mm engineered sheathing board screwed to studs, providing diaphragm shear resistance and racking strength.

5

140mm S350GD C-Studs + In-Stud Rockwool Insulation

Galvanized steel structural studs with 100-140mm non-combustible mineral rockwool (Euroclass A1) for acoustic and thermal barrier.

6

Vapor Control Membrane & 12.5mm Interior Gypsum Finish

Taped airtight vapor retarder membrane + 12.5mm interior plasterboard ready for painting or wallpaper.

High-Performance Wall Cross-Section Render

Multi-Layer High-Performance Wall Envelope

Thermal & Acoustic Ratings

Certified European Standard Metrics

Overall Wall Thermal Transmittance

U = 0.12 – 0.16 W/m²K

Exceeds German GEG 2024 & French RE2020 standards

Airborne Sound Insulation

Rw + Ctr ≥ 56 dB

Fire Resistance Rating

REI 60 / REI 90 / REI 120

Explore All Wall, Floor & Roof Cross-Sections

Structural Comparison

LGSF Steel vs. Reinforced Concrete vs. Timber Frame

An objective technical comparison of the three primary structural methods used in European residential villa construction.

Engineering Parameter	★ LGSF Light Gauge Steel (SerVilla)	Traditional Reinforced Concrete	Timber Frame (Wood)
Structural Dead Weight	35 – 50 kg/m² (Ultra-light, reduces foundation cost by up to 40%)	300 – 450 kg/m² (Heavy foundation loads)	70 – 95 kg/m²
Seismic Resistance (Eurocode 8)	Superior (PGA ≥ 0.40g, high ductility, non-brittle)	Moderate (Rigid & brittle, high inertia mass)	Good (Flexible, lightweight)
Termite, Fungi & Rot Immunity	100% Immune (Inorganic galvanized steel)	Immune to pests, susceptible to water ingress	High risk (Requires chemical treatments)
Dimensional Stability & Warping	0% Warping / Shrinkage (Permanent precision)	Settlement cracking risk over 2-5 years	2 – 5% seasonal expansion/contraction
On-Site Superstructure Assembly	5 to 12 Days (Dry assembly, zero curing wait)	6 to 12 Months (Formwork, wet curing delays)	3 to 6 Weeks
Manufacturing Tolerance	±0.5 mm CNC Controlled	±15 – 30 mm (High on-site manual variance)	±2 – 5 mm
Recyclability & Circular Economy	100% Infinitely Recyclable Steel	Demolition rubble (High environmental burden)	Biodegradable (Treated wood requires disposal)

Digital Fabrication

From 3D BIM Model Directly to CNC Roll-Forming

Every villa begins as a fully coordinated 3D Building Information Model (BIM) in Revit, Vertex BD, or Archicad. Our software calculates every load-bearing profile, connection gusset, hold-down anchor, and service penetration before a single coil of steel is unrolled.

✓ Direct CNC Machine Code (NC / CSV): Profiles are punched, notched, dimpled, and cut to exact millimetric length automatically.

✓ Element-by-Element Inkjet Numbering: Every single stud and track is printed with a unique tracking code matching the 3D assembly blueprint.

✓ Pre-Punched MEP Service Holes: Electricians and plumbers run conduits through pre-aligned factory chaseways with zero site drilling.

Explore Engineering Hub Submit CAD Drawings

Automated CNC Roll Forming Line & 3D BIM

Direct BIM-to-CNC Roll Forming Integration

Deep Technical Chapters

Explore Specialized LGSF Material & Engineering Guides

In-depth technical dossiers covering cold-formed metallurgy, multi-layer wall physics, roof trusses, Passivhaus thermal envelopes, and Eurocode 8 seismic behavior.

Eurocode 3 & 8 · Passivhaus · RE2020 · GEG 2024

Building Assemblies, Technical Cross-Sections & U-Values

Explore complete layer-by-layer stratigraphies for exterior walls (U = 0.11–0.15 W/m²K), acoustic decoupled party walls (Rw up to 62 dB), L/500 stiff floor cassettes, and alpine roof assemblies with full specification comparison matrix.

Explore Technical Cross-Sections

S350GD+Z275 · EN 10346

Light Gauge Steel Framing & Metallurgy

Discover S350GD structural yield strength, continuous 275 g/m² hot-dip zinc cathodic barrier, and 50+ year corrosion resistance.

Read Metallurgy Guide

6 Layers · U ≤ 0.14

6-Layer Advanced Wall Anatomy

Breathable vapor-permeable membranes, exterior BoardeX sheathing, dense rockwool cavity cores, and exterior ETICS insulation.

Explore Wall Anatomy

12m Spans · L/500 Deflection

Roof Trusses & Structural Flooring

Clear-span triangulated lattice trusses up to 12+ meters without internal columns, alpine snow loads, and stiff acoustic floor joists.

Explore Roof & Floors

GEG 2024 · RE2020

Thermal Performance & Passivhaus

Elimination of thermal bridging, triple-glazed low-E argon windows, airtight building envelopes, and 60% lower HVAC bills.

Review Thermal Physics

Eurocode 8 · NTC 2018

Eurocode 8 Earthquake Resistance

Why lightweight structural physics (F=m*a) and high ductility factor (q ≥ 3.0) make LGSF the safest system in seismic zones.

Read Seismic Engineering

REI 120 · 56 dB Acoustic

Acoustic Soundproofing & Fire Safety

Mass-spring-mass sound isolation rating (Rw ≥ 56 dB), non-combustible A1 rockwool cores, and certified REI 60/90/120 fire barriers.

Read Acoustic & Fire Guide

Eurocode 2/7 · -40% Concrete

Foundation Systems & Ground Anchors

Up to 40% reduction in concrete slab volume, heavy-duty Simpson hold-downs, M16/M20 chemical anchors, and screw-piles for sloping terrain.

Explore Foundation Systems

Z275 Galvanization · C4/C5 Marine

Galvanic Corrosion Protection

Self-healing sacrificial zinc passivation, enclosed dry wall physics, and 100+ year durability in coastal marine environments.

Explore Durability Science

Pre-Punched MEP · Smart Home

Pre-Engineered MEP & Smart Home

Precision factory-punched service chaseways for electrical conduits, PEX plumbing, and MVHR ventilation without on-site cutting.

Review MEP Integration

Engineering Questions

Frequently Asked Questions: LGSF Technology

Technical answers regarding steel grades, thermal performance, acoustic decoupling, and fire safety ratings.

Quelle nuance d'acier et quelle galvanisation SerVilla utilise-t-elle pour les profilés LGSF ?

Nous utilisons exclusivement de l'acier de structure S350GD+Z275 certifié EN 10346 (limite d'élasticité 350 MPa) avec galvanisation à chaud de 275 g/m², garantissant plus de 100 ans de longévité même en bord de mer.

Comment les ponts thermiques sont-ils éliminés dans un mur à ossature acier ?

Les ponts thermiques sont neutralisés par une isolation thermique par l'extérieur (ITE) continue de 50 à 100 mm combinée à 100-140 mm de laine de roche entre montants, atteignant des coefficients U de 0,12 à 0,16 W/m²K (norme Passivhaus).

Quelles performances de résistance au feu (REI) les parois en acier atteignent-elles ?

Les parois standard atteignent la classification REI 60 grâce à la laine de roche incombustible (Euroclasse A1) et aux plaques coupe-feu. Des configurations renforcées permettent d'atteindre REI 90 et REI 120 certifiés.

Comment l'isolation phonique et acoustique est-elle assurée dans une villa en acier ?

Nos parois multicouches offrent un indice d'affaiblissement acoustique supérieur à Rw + Ctr ≥ 56 dB. Les planchers intermédiaires intègrent des bandes résilientes de désolidarisation acoustique absorbant les bruits d'impact.

Quelles tolérances de fabrication les profileuses industrielles CNC garantissent-elles ?

Tous les profilés en C et en U, les pré-perçages techniques et les emboutissages sont formés par profileuses CNC avec une tolérance de ±0,5 mm sur 6 mètres, garantissant un assemblage vissé sans aucune découpe ni soudure sur chantier.

Light Gauge Steel Framing (LGSF) Technology