Heat, air and moisture interact
Building physics explains how assemblies interact with indoor and outdoor conditions. Conduction, heat carried by air and radiation are different mechanisms. Moisture can arrive as rain, ground water, vapour diffusion or air leakage. The relevant assessment follows the mechanism; not every defect should automatically be described as a “dew-point problem”.
Move from material to junction
A material property applies under defined conditions. In an assembly, thickness, connections, fixings and inhomogeneity become relevant. Flat-layer resistance does not describe temperature at a corner or floor edge. Explaining a cold surface needs geometry and boundary conditions; evaluating drying needs the routes by which moisture enters and leaves.
Distinguish steady and changing conditions
One winter temperature does not describe annual behaviour. Sun, wind, occupation and heat storage vary over time. A massive assembly can delay temperature change, but does not create an unlimited reserve of cooling or heat. For a question governed by a daily cycle, static resistance is only part of the explanation. The method should match the time scale as well as the physical process.
Choose a practical check
Identify the symptom: energy demand, local cooling, a wet layer or overheating. Gather conditions and select the relevant R/U, junction, airtightness or moisture guide. Do not replace membranes or insulation on the basis of one reading without examining the cause. A professional model needs stated assumptions; a measurement needs location, date and method. Those details make it possible to compare evidence with the actual question instead of treating every available number as equally informative.
