There are multiple reasons why moisture can enter a building structure, but for the purpose of this article we will look at how to detect moisture using electronic equipment.
But what is moisture?
Moisture can be found throughout the building structure in differing levels and can fluctuate throughout the year. For most of the time, this will be minor atmospheric moisture absorbed by the building material or covering (wall paper and flooring).
However, moisture is a hazard long before you see it and will not become visibly damp until it is too late. Degradation of the material will start before it can be detected with human senses like touch.
Building materials are like sponges, featuring a porous structure which absorbs water. If water enters a property, it can travel for the primary source to a secondary material. This ‘diffusion’ drives the mositure to dry areas and eventually the surface where you would normally encounter a problem.
Surface moisture can dry through evaporation caused by air movement. But in most cases the surface has a covering (wall paper, paint or wood flooring) which acts as a barrier stopping evaporation. Initially you will not encounter a problem until the moisture level reaches a point that causes the covering to lift, peel or crack.
When undertaking an inspection of a property, a good surveyor should check both the surface and sub-surface moisture levels. This will ensure that any potential problems are spotted before it’s too late.
How to detect moisture
When undertaking a moisture reading of a building structure, there are three test that can be performed; surface moisture reading, sub-surface moisture reading and humidity.
Protimeter Mini taking a reading with pins
1. Surface Moisture Readings
Measuring the surface moisture is a relatively simple process utilising a pin type electronic moisture reading device.
Both the Protimeter Mini and Protimeter Surveymaster incorporate two metal pins at the top of the instrument. By placing these pins on the surface, the instrument reads the moisture levels between the pins. Higher the water level will generate a higher moisture reading.
The readings are displayed through a simple coloured LEDs. Green for good, yellow for borderline and red for bad. So simply, if the reading is in the green the moisture level is at a 'no risk' level.
If the reading displays a yellow LED, the surveyor should determine if further inspection of the building structure should be undertaken. If the reading is in the red, the moisture level is too high and the surveyor should undertake a further assessment.
With the Protimeter Surveymaster, the readings are supported with a LCD display providing a digital reading of the moisture level.
2. Sub-surface Moisture Readings
Sub surface readings are an important indication of the moisture condition of the building structure. More moisture will be locked inside the building material than on the surface.
Protmeter Surveymaster using the search mode
Non-invasive
Protimeter has developed a non-invasive search mode which penetrates to a depth of 20mm. The return signal will be displayed digitally through a simple LCD display between 0 to 1000 REL. The REL stands for relative reading and is an indication of the moisture level.
Again a simple LED display employed to provide a quick determination of the reading. If the moisture level is too high, a further invasive test should be undertaken.
Both the Protimeter Aquant and Protimeter Surveymaster are equipment with this method of moisture detection.
Protimeter Mini using deep wall probes for electrical conductivity test
Electrical Conductivity
One further method for measuring sub-surface moisture is to drill two holes and pass a deep wall probe into the wall. The moisture readings are measured by the electrical conductivity through the material. Higher the reading the larger amount of water is present. This provides an important additional check to determine the extent of moisture in a material like a wall or concrete structure.
This can be undertaken with the Protimeter Mini, Protimeter Surveymaster and Protimeter MMS2 models.
Protimeter MMS undertaking a humidity and condensation test
Commonly within a property a high level of humidity will be generated through general living conditions. Either through cooking, taking a shower or even breathing, moisture will be released into the environment.
Without proper air circulation, the first thing you may see is condensation on windows or tiles. In server conditions, wall paper will start to peel off and mould will grow.
By utilising a Protimeter Hygromaster, Protimeter Pysclone or Protmeter MMS2, the surveyor will be able to take a digital reading of the humidity levels.
All readings are displayed as a %RH (Relative Humidity) supported with either a temperature reading or dew point reading.
If the reading is above 70%RH, the moisture levels within the environment are high enough for bacteria to grow. It’s the bacteria that breaks down the building materials and causes damage.
With the Protimeter MMS2, a condensation test can be performed. This runs through the relevant moisture and temperature readings to determine if there is a condensation issue.
Further Reading
If you would like more information on moisture
Dampness Measurement in Concrete Floors
How to Measure Moisture in Buildings
If you would like more information on the Protimeter range, please visit www.damp-meter-direct.co.uk
Protimeter Mini
Protimeter Aquant
Protimeter Surveymaster
Protimeter Hygomaster
Protimeter Pysclone
Protimeter MMS2
