Eristysmallin

Eristysmallin is a Finnish term that refers to an insulation model, a mathematical or empirical representation of how thermal insulation affects heat transfer in a building element. In building physics, eristysmallin describes a model used to estimate thermal performance such as U-values, R-values, and heat flux through walls, roofs, or windows. Models can be simple one-dimensional steady-state calculations using material thickness, thermal conductivity, and contact resistances, or more complex dynamic or multi-layer models that account for transient temperature variations, moisture effects, and thermal bridges.

Applications include informing design decisions, energy performance simulations, and compliance with building energy codes and standards. Eristysmallin is often employed in conjunction with material data sheets, lab measurements, and software tools used in building energy simulation (for example lumped-parameter or finite-volume models).

In Finnish technical literature, the term is used across contexts from product documentation to academic research. The exact scope of an eristysmallin can vary by project, ranging from a simple equivalent insulated layer to comprehensive models of multi-layer assemblies.

See also: Thermal insulation, U-value, Thermal conductivity, Building physics.