Humiditect Condensation Indicators

Although condensation is probably the most common form of dampness in buildings, it is notoriously difficult to diagnose. One of the main reasons for this is the fact that levels of RH vary throughout the day. For example, RH may be low during the day when a surveyor takes an RH reading. However, the RH will rise in the evening when the occupants return to the house, due to vapour produced by breathing, washing, and cooking.

The Humiditect condensation indicator card gets round this problem by giving a visual signal that a level of RH high enough to present a potential condensation risk has been breached during a given period. The special single-use card is placed in a room where condensation is suspected for a period of at least a week. Special indicator spots on the card show the highest level of RH reached during this period, expressed as a “condensation risk”.

The cards are used as follows:

Identify the area where you suspect moisture contamination is occurring.
Open airtight sachet and remove the Humiditect card.
Fix the card to a wall using a pin or double-sided tape.
Leave the Humiditect card in position for as long as possible to allow several potential phases of condensation to occur. We recommend seven days, but indications can occur after two days.
In severe cases of condensation, water may run down the wall. To prevent water contamination of the Humiditect surface, the card’s top edge should be bent forwards to protect the indicator spots. After a period of 7 days some of the indicator spots will have started to ‘bleed’ or spread when a set RH has been reached. (Relative Humidity is the amount of water vapour in the air at a given time)