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Corner Psi-Value
Ψ <= 0.010 W/mK
Window Jamb Psi
Ψ <= 0.015 W/mK
Slab Edge Psi
Ψ <= 0.020 W/mK
Temp. Factor (fRsi)
fRsi >= 0.75 (>0.70 min)
Analysis Standard
ISO 10211 2D/3D FEM
Condensation Risk
%0 (Sıfır Riski)
ISO 10211 Compliant Thermal Decoupling (Psi <= 0.010 W/mK)

Thermal bridges in steel homes | SerVilla

Steel elements and discontinuities at envelope junctions can increase heat transfer.

Engineering Drawing & Physical Cross-Section
CAD/CAM Scale 1:1 Reference
THERMAL BRIDGE MODELLING: CONVENTIONAL CORNER VS SERVİLLA PASSIVE ENVELOPE ISO 10211 Finite Element Heat Flux Simulation • fRsi Temperature Factor Analysis CONVENTIONAL JUNCTION (THERMAL BRIDGES PRESENT) 11.2°C Condensation & Mold Risk! Ψ = 0.085 W/mK • fRsi = 0.61 (<0.70 Below Threshold) SERVİLLA PASSIVE ENVELOPE (ZERO THERMAL BRIDGES) 18.6°C Completely Dry & Homogeneous Ψ ≤ 0.010 W/mK • fRsi = 0.78 (Superior Comfort)
LIVE SIMULATOR

Thermal Bridge Penalty & Heat Loss Simulator

ISO / EN Compliant Math

Compare linear thermal transmission (Psi), annual kWh penalty, and internal surface temperature (fRsi) between conventional concrete slabs and SerVilla thermally-decoupled CFS assemblies.

Linear Transmission Loss
38 kWh/yr
Psi x Length x Degree-Hours
Interior Surface Temp (Tsi)
18.4 °C
Based on 20°C indoor air
Temperature Factor (fRsi)
fRsi = 0.78
ZERO MOLD RISK (fRsi >= 0.75)
Heat Leak Avoided
%98.2
vs Conventional Concrete
1:1 CAD/CAM Detail Eurocode 3 • Passivhaus • DIN 4108

Interactive Architectural Sections & Junction Details

Explore the layer-by-layer anatomy of walls, floors, foundations, roofs and precision window installation interfaces.

✓ 1 Systems • High-Precision Details

Junction 1: Floor-to-Exterior Wall Rim Track Junction

Interface where intermediate floor joists bear onto the exterior load-bearing wall. Continuous external rockwool eliminates thermal bridging at the rim joist; internal smart vapour membrane is taped continuously around the floor cassette, complemented by an intumescent fire-stop cavity barrier.

Ψ ≤ 0.010 W/mK • Continuous EWI • Compartment Fire Stop
Thermal Bridge (Ψ)
Ψ ≤ 0.010 W/mK
Temp Factor (fRsi)
fRsi ≥ 0.75 (Condensation-Free)
Fire Resistance
REI 60 Inter-Storey Fire Stop Barrier
Airtightness
Continuous Red Airtight Line Tie-In Tape
CAD/CAM PRECISION • CROSS SECTION 1:1 VECTOR SPEC ONLINE INTERACTIVE
INTERMEDIATE FLOOR & EXTERIOR WALL RIM TRACK JUNCTION Ψ ≤ 0.010 W/mK 1 2 3 4 5 6 FLOOR-WALL RIM TRACK SPECIFICATION: [1] Continuous 120 mm EWI (Zero Rim Joist Thermal Bridge) [2] BoardeX Structural Exterior Sheathing (Shear Load Transfer) [3] C200 Rim Track & Rockwool Compartment Fire Stop [4] Acoustic Vibration Decoupling Strip (EPDM Impact Underlay) [5] Floor Structural Slab & Screed / Underfloor Heating [6] Inter-Storey Airtight Red Line Sealing Tape RIM TRACK JUNCTION DETAIL Ψ ≤ 0.010 W/mK • REI 60 Compartment Fire Stop • n50 ≤ 0.60 Airtightness Loop

Physical Layer Breakdown & Material Specification

6 Layers
1 Render + Continuous 120 mm Rockwool EIFS
P3
130 mm λ: 0.035 W/mK μ: 1.0 A1
Continuous external thermal blanket
2 External Structural Sheathing Board
P2
12.5 mm λ: 0.25 W/mK μ: 15 A1
Shear diaphragm transfer
3 CFS C200 Rim Track + Fire-Stop Cavity Barrier
P1/P2
200 mm λ: 0.034 W/mK μ: 1.0 A1 / EI60
Load transfer and compartment fire-stop
4 Acoustic EPDM Resilient Strip
P4
10 mm λ: 0.12 W/mK μ: 8000 B2
Impact noise and flanking vibration break
5 Structural Floor Deck & Screed with UFH
P4
70 mm λ: 1.20 W/mK μ: 30 A1
Thermal mass and comfort layer
6 Inter-Storey Airtight Loop Seal
P2
0.5 mm λ: 0.20 W/mK μ: Sd=25m E
Continuous airtight envelope seal
Scroll horizontally to view all layer parameters 6 Layers
No Material & Layer Specification Thickness Conductivity (λ) Vapour / Sd Fire Class Delivery Package Building Physics Function
1 Render + Continuous 120 mm Rockwool EIFS 130 mm 0.035 W/mK 1.0 A1 P3 Continuous external thermal blanket
2 External Structural Sheathing Board 12.5 mm 0.25 W/mK 15 A1 P2 Shear diaphragm transfer
3 CFS C200 Rim Track + Fire-Stop Cavity Barrier 200 mm 0.034 W/mK 1.0 A1 / EI60 P1/P2 Load transfer and compartment fire-stop
4 Acoustic EPDM Resilient Strip 10 mm 0.12 W/mK 8000 B2 P4 Impact noise and flanking vibration break
5 Structural Floor Deck & Screed with UFH 70 mm 1.20 W/mK 30 A1 P4 Thermal mass and comfort layer
6 Inter-Storey Airtight Loop Seal 0.5 mm 0.20 W/mK Sd=25m E P2 Continuous airtight envelope seal
Delivery Package Demarcation Lines:
P1: P1: Structural Light Gauge Steel Frame & Anchors
P2: P2: Frame + Sheathing + Cavity Insulation + Vapour Control
P3: P3: Weather-Tight Shell (Continuous EWI + Windows + Roof Waterproofing)
P4: P4: Internal Service Zone + Screed + Double Lining / Finishes

All cross-sections are engineered to Passive House Institute (PHI) standards, Eurocode 3 cold-formed steel rules and DIN 4108 condensation criteria. Contact our engineering desk for project-specific calculations.

Discuss This Section With Our Engineers

Technical Specifications & International Standards

Design criteria verified against Eurocode, ISO and DIN standards.

Verified Assembly
Critical Junction Standard Practice Risk SerVilla Engineering Detail Target Thermal Metric
Exterior Steel Studs Thermal bypass along steel flange due to metal conductivity 100-160 mm continuous EWI fully wraps studs, isolating them from cold exterior air ΔU <= 0.01 W/m²K
Window & Door Sub-Frames Window anchored directly to metal framing causing perimeter frost Frames positioned in insulation zone with warm-edge pre-wall brackets Ψ <= 0.015 W/mK
Slab Foundation Interface Uninsulated concrete slab perimeter creating severe heat drain 100 mm perimeter XPS skirting joined directly to wall EWI insulation Ψ <= 0.020 W/mK
Roof Eaves & Gable Junctions Gap between attic insulation and wall insulation causing draft Continuous overlap of wall rockwool into roof rafters with taped air barrier Ψ <= 0.010 W/mK
Balconies & Cantilevers Structural beams protruding outside acting as thermal radiator fins Self-supporting exterior post-and-beam balconies; zero envelope penetration Ψ = 0.000 W/mK (Sıfır Köprü)
PHYSICS PROOF

ISO 10211 Temperature Factor (fRsi) & Zero-Mold Guarantee

$$ f_{Rsi} = \frac{\theta_{si} - \theta_e}{\theta_i - \theta_e} = \frac{18.6 - (-10)}{20.0 - (-10)} = \frac{28.6}{30.0} = 0.78 \ge 0.70 $$

To avoid mold and moisture accumulation to DIN 4108-2, the temperature factor fRsi must exceed 0.70. With SerVilla continuous exterior rockwool wrap, the internal corner surface temperature is maintained at θsi = 18.6°C even when outside is -10°C. The resulting fRsi = 0.78 completely eliminates surface condensation risks.

Failure Mode Analysis: Conventional Errors vs SerVilla Mitigation

Comparative building physics study showing failure points avoided by SerVilla design.

RISK MITIGATION
Direct Thermal Conduction Through Balconies and Parapets EN ISO 10211 / PHI Psi <= 0.010 W/mK
Conventional Failure Risk

Cold surface band on indoor floor (12°C), thermal shock cracking, and 30% added winter energy cost.

SerVilla Engineering Solution

SerVilla engineers self-supporting external balconies on separate steel posts or uses load-bearing structural thermal breaks.

Window Frames Fixed Directly to Bare Steel Substructure DIN 4108 Beiblatt 2
Conventional Failure Risk

Perimeter black mold colonization (fRsi < 0.70) and radiant cold discomfort around joinery.

SerVilla Engineering Solution

Windows are bracket-installed directly within the external insulation layer with expanding airtight tape; Psi_inst <= 0.02 W/mK.

BIM LEVEL 2 / OPENBIM SPECIFICATION

BIM Specification & Structural Data Sheet

IFC 4 / ISO 16739-1
IFC Data Schema
IFC 4 Thermal Bridge Attribute Set (Pset_ThermalBridgeType)
Fire Reaction Class
A1 Non-Combustible Thermal Spacers
Acoustic Sound Index
Decoupled Gasket Vibration Attenuation (-6 dB)
Durability & Lifetime
fRsi >= 0.75 Certified No Mold Risk (ISO 13788)
CE Declaration of Performance
FEM-2D-ISO10211 Verified Report SV-TB-01
Material Specification
EPDM Compression Gaskets + Continuous 120-160mm Rockwool Facade

Governing Standards & Eurocode Norms

Thermal-bridge free engineering with Psi <= 0.010 W/mK eliminates condensation and mold formation.

EN ISO 10211 EN ISO 10077 DIN 4108 Bbl 2 fRsi >= 0.75
Passive House / Passivhaus KfW / Effizienzhaus 40–55 Minergie, Minergie-P, Minergie-A and ECO CasaClima / KlimaHaus and Nature

Thermal Bridge Physics & Finite Element Modeling

01

2D/3D FEA Modeling (ISO 10211)

Critical connection details modeled in THERM/ANSYS software with 0.1°C resolution to verify isothermal lines.

02

fRsi Temperature Factor (>= 0.75)

Ensures internal surface temperature never drops below 12.6°C. fRsi >= 0.75 mathematically prevents mold growth.

03

Steel Stud Exterior Thermal Shield

Steel studs are shielded from ambient cold by minimum 100 mm continuous external insulation, keeping metal warm.

04

Self-Supporting Cantilever Philosophy

Canopies and balconies are thermally decoupled or self-supported on exterior pillars, avoiding envelope puncture.

5-Point On-Site Quality Assurance Checklist

1
Corner Thermal Wrapping: Exterior insulation panels interlocked at corners without through-gaps.
2
In-Insulation Window Positioning: Frames set within the thermal insulation zone and overlapped by 30 mm insulation.
3
Slab Perimeter Continuity: 100 mm XPS foundation insulation seamlessly abutted to wall EWI with zero gap.
4
Freestanding Cantilever Audit: Visual confirmation that balconies are self-supported without structural envelope penetration.
5
Preliminary Infrared Scan: Thermographic scan under differential temperature to detect anomalous thermal flux lines.

3. Thermal Bridge Elimination & ISO 10211 Finite Element Modeling

Because structural steel possesses higher thermal conductivity than timber or masonry, thermal bridge management is the core discipline of high-performance CFS engineering. SerVilla applies a strict "continuous thermal envelope" methodology, ensuring no metal component ever makes direct physical contact with ambient outdoor cold.

Critical Building Physics Details

  • Stud Flange Decoupling: Continuous exterior insulation (100-160 mm EWI] encapsulates all outer steel flanges. The linear thermal bridge effect across studs is reduced to near-zero (ΔU <= 0.01 W/m²K].
  • Window Reveal & Sill Detailing (Ψ <= 0.015 W/mK]: Windows are mounted in the plane of the continuous insulation using thermal brackets. The frame is overlapped by 30 mm of exterior insulation, eliminating perimeter thermal leaks.
  • Slab-to-Wall Foundation Interface (Ψ <= 0.020 W/mK]: High-density XPS perimeter skirting wraps the exposed concrete slab edge, meeting the wall insulation without a thermal gap.
  • Balconies and Cantilevers (Ψ = 0.000 W/mK]: Structural penetrations for balconies act as enormous cooling fins. SerVilla designs exterior balconies as freestanding, thermally decoupled post-and-beam assemblies that never pierce the conditioned envelope.

EN ISO 10211 FEA Modeling & fRsi Verification

All architectural junctions are modeled in compliance with EN ISO 10211 using 2D/3D finite element heat flux software. The internal surface temperature factor is certified at fRsi >= 0.75 (comfortably exceeding the 0.70 statutory mold threshold], guaranteeing that surface temperatures stay above 18°C even at -10°C external winter temperatures.

SerVilla Engineering Note: Details documented in this specification are engineered project-specifically based on local soil conditions, statutory climate data, wind/snow loads and chosen energy targets (PHI, KfW 40, Minergie). Certified execution drawings govern contracts.

Explore Other Building Physics Modules

Structural Steel Frame Wall Build-Ups & Cavity Airtightness & Membranes Triple Glazing & Shading Roof & Foundation Interface MVHR Ventilation & Heat Pumps PHPP & Blower Door Testing

Consult Our Engineering Desk on This Technical Assembly

Receive preliminary thermal bridging calculations and structural CFS advice directly from our senior engineering team.

Consult via WhatsApp

Explore Other Model Concepts

Compare alternative footprints, storey options and spatial arrangements.

Important Note: Veranda, garage, terrace, pool, BASEMENT FLOOR, etc. are NOT included in areas & PRICES. Semi-detached / twin models: 1 unit basis.
Model 25-1003 — 99 m², 1 storey
Model 25-1003 Farmhouse & Ranch

Model 25-1003 • 99 m²

Model 25-1003 — 99 m², 1 storey

1 Storey
2 Bedrooms
1 Garage
Explore Design
Model 25-1004 — 114 m², 1 storey
Model 25-1004 American Style

Model 25-1004 • 114 m²

Model 25-1004 — 114 m², 1 storey

1 Storey
3 Bedrooms
1 Garage
Explore Design
Model 25-1005 — 135 m², 1 storey

Model 25-1005 • 135 m²

Model 25-1005 — 135 m², 1 storey

1 Storey
3 Bedrooms
0 Garage
Explore Design

Frequently Asked Questions

Essential answers regarding steel construction, energy targets and project delivery.

While steel has higher thermal conductivity than timber or masonry, the physics solution is straightforward: absolute decoupling. SerVilla wraps the entire steel framing with 100-160 mm of continuous exterior rockwool or graphite EPS insulation. The steel skeleton remains entirely inside the warm conditioned space, reducing linear thermal bridge values to Psi <= 0.010 W/mK.

In standard buildings, thermal bridges cause cold wall corners and draft sensations through radiant cooling. In a SerVilla home, all internal surface temperatures remain within 1-2°C of the indoor ambient temperature (at least 18.5°C when the room is 20°C). Cold drafts and floor chills are eliminated.

Our building physicists perform numerical 2D/3D thermal simulations strictly adhering to EN ISO 10211. Detailed calculation sheets showing fRsi temperature factors and heat flux profiles are provided for local building control and energy rating assessors (KfW, PHI, SEAI).

Windows are not fastened directly against cold steel. They are set into the continuous thermal insulation layer using thermal pre-wall brackets and sealed with multi-functional expanding foam tapes (RAL/DIN standard), achieving junction Psi values below 0.015 W/mK.

Cantilevered slabs that penetrate the envelope act as giant heat sinks and are prohibited in certified passive builds. SerVilla specifies self-supporting balconies mounted on independent exterior pillars, completely decoupled from the conditioned thermal boundary.

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