Before answering, let\u2019s review a few basic concepts.<\/p>\n\n\n\n
Relative humidity (RH)<\/strong>, expressed as a percentage and displayed on household sensors or weather stations, represents the amount of water vapor in the air relative to the maximum amount the air can contain at that temperature (100%). The term \u201crelative\u201d is no coincidence: the value depends on temperature<\/strong> (and also on pressure, although its effect is negligible for our purposes). During our training courses, we use the analogy of a sponge: air is like a sponge that becomes increasingly \u201csqueezed\u201d as it gets colder. If we pour water onto a dry sponge, it will absorb the water without dripping. The amount of water we pour in represents absolute humidity<\/strong>. There are two ways to make the sponge start dripping.<\/p>\n\n\n\n In this second case, the absolute humidity does not change; what changes is the air\u2019s capacity to hold water vapor, and therefore its relative humidity. We can go from, for example, 60% relative humidity to 100%. This explains a phenomenon that may seem strange at first: condensation can form on a radiant floor even when it is neither raining nor foggy outside.<\/strong><\/p>\n\n\n\n\n