What is a Calcium Carbide Test?

29 August 2014

At Timberwise our team of damp proofing specialists have a variety of tools at their disposal to identify dampness in properties. One such tool is the Speedy Carbide Test. In this blog post we look at the Speedy Carbide Test and how it helps in the identification of dampness in properties.

A speedy carbide test is an item of apparatus used by damp specialists to determine the moisture content within a damp wall. The test aids our surveyors when investigating a property for damp and helps to determine an accurate diagnosis of the dampness within the property. A speedy carbide test has a greater degree of accuracy when compared to a Protimeter that also determines the moisture levels within a damp wall. Unlike the Protimeter the speedy carbide test is a destructive test and requires a sample from the wall or floor. As a result a Speedy Carbide Test tends to be only carried out if it is specifically requested by the owner of the property.

How does the test work?

The apparatus itself contains a sealed vessel that is thoroughly cleaned before each test is carried out; this prevents any discrepancies with the results and provides an accurate reading. The surveyor will then drill a hole in the affected wall to get a sample of the masonry to test the moisture content.

Ensuring the container is cleaned

The sample is then weighed using the scales on the apparatus and poured into the flask standing vertically. Once the sample is placed carefully within the flask, 2 measurements of calcium carbide are measured out and placed into the lid of the flask, ensuring the two substances do not mix. The lid is then securely placed on the flask, still being held vertically and then shaken vigorously to mix the substances together.

Measuring the sample of affected wall

Pouring the sample carefully

Adding the calcium carbine reagent

By mixing the sample and the calcium carbide together, any moisture within the sample reacts with the calcium carbide and releases an acetylene gas. This gas builds up within the flask turning the dial at the bottom of the flask, allowing the surveyor to calculate the percentage of moisture within the sample. If the reading is above 4% the moisture levels within the affected walls, this is a high moisture content. In the example shown below the reading is showing a reading of almost 0% indicating no moisture is present in the sample.

Sealing the cylinder securely

Mixing the substances together

Results shown on the dial

If you suspect that you may have a damp issue that needs a damp survey don’t hesitate to get in touch with our damp proofing specialists. Call your local office on 0800 288 8660 or request a damp survey using our on-line survey request form.