Matériaux Database
Matériaux Database
Searchable catalog of building materials with lambda values, categories, and practical notes.
Search for a material, choose a category, and sort by lambda or name.
A practical reference for lambda values
Compare materials quickly
Use the table to shortlist insulation, structure, and finishing materials by thermal conductivity before you build the assembly.
Check realistic values
Lambda values vary by product type, density, and manufacturer. The catalog is a fast reference, not a substitute for technical data sheets.
Feed the calculator
Once you have a likely material, move back to the calculator and test the full wall, roof, or floor build-up with the chosen thickness.
How lambda becomes resistance
Lower lambda means better insulation
A lower lambda value usually means the material resists heat flow better. That is useful when insulation thickness is limited.
Category helps you find the right use case
Not every low-lambda material belongs in every place. Some are meant for walls, some for roofs, some for floors, and some for finishing layers.
If you need the best result for a specific assembly, compare the material table with the wall, roof, or floor guide first, then check the final U-value in the calculator.
How lambda becomes resistance
R = d / lambda
Once thickness is known, the material table lets you estimate the resistance of the layer.
U = 1 / (Rsi + sum(R layers) + Rse)
That is the link between a single material and the final performance of the full assembly.