Guide
Steel frame guideSteel frame insulation thickness guide
Steel frame walls need a careful look at insulation thickness because steel can create strong thermal bridges.
Used for quick thermal checks of walls, roofs, and floors.
Guide page based on a 14 cm reference wall leaf.
The reference build-up uses a wall leaf, insulation, and finish layers.
The example U-value gives a quick orientation for the guide.
Steel frame insulation thickness guide worked example
This guide turns the general formula into a wall-specific thickness decision page.
| Layer | Material | Thickness | Lambda | R |
|---|---|---|---|---|
| Layer | Material | Thickness | Lambda | R |
|---|---|---|---|---|
| Interior finish |
Gypsum plaster
Interior finish
|
1.5 cm | 0.700 W/mK | 0.02 m²K/W |
| Structural steel |
Structural steel
Steel frame members
|
14 cm | 50.000 W/mK | 0.00 m²K/W |
| Mineral wool |
Mineral wool
General insulation
|
15 cm | 0.035 W/mK | 4.29 m²K/W |
| External finish |
Silicone render
Facade finish
|
1.5 cm | 0.870 W/mK | 0.02 m²K/W |
| Surface resistances | 0.17 m²K/W | |||
| Total resistance | 4.50 m²K/W | |||
How the guide estimate works
R = d / lambda
The guide starts with a base wall, adds insulation, and shows the remaining thermal resistance available for the target U-value.
U = 1 / (Rsi + sum(R layers) + Rse)
That makes the page useful for search, but the calculator remains the right tool for exact project work.
Related wall pages
How To Calculate U Value
Open how to calculate u value for the next step in this journey.
Open next stepInsulation Thickness Calculator
Open insulation thickness calculator for the next step in this journey.
Open supportOpen the calculator
Use the main calculator to edit layers, compare materials, and export a custom result.
Open calculatorR-value vs U-value
Compare the two thermal metrics before choosing a wall or roof build-up.
Open comparisonThis page is a reference estimate for search and comparison use.
The guide is deliberately practical and search-focused so it stays useful on first load.
A full project check should include thermal bridges and the actual framing layout.
The page supports the wider wall content cluster and leads users back to the main calculator.