Free online tool to analyze condensation risk in multi-layer walls instantly. Identify interstitial condensation points in seconds to prevent mold. No sign-up required.
Condensation risk predicts if your windows or walls will sweat. It compares the surface temperature to the room's dew point.
1D steady-state heat transfer. Condensation occurs where layer temperature ≤ indoor dew point.
Rule of Thumb: Insulation should ideally be placed on the cold exterior side to keep inner wall layers warm and above the dew point.
Checklist: Add wall layers from inside out. Set R-values. Look for the ⚠ warning sign indicating interstitial condensation.
Quick Tip: Use a vapor retarder on the warm side of the assembly to block moisture from entering the cold cavity.
Condensation occurs when the temperature at any point within the wall layers drops below the dew point of the air migrating through it.
Adding a vapor barrier on the warm side of the insulation and ensuring adequate external ventilation are standard methods to prevent interstitial condensation.
It calculates the temperature gradient across the wall layers from inside to outside, allowing you to see exactly where the temperature crosses the dew point line.
This tool uses a 1D steady-state method which provides a good baseline estimate. For complex walls with thermal bridging or dynamic weather patterns, a 2D or 3D transient hygrothermal analysis is recommended.