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Water leaks and moisture infiltration may result in substantial defects on a building. Water permeating through masonry or concrete sections can be difficult to detect until it’s too late. Using a thermal imaging camera and under the right circumstances, it’s possible to find hidden water and moisture issues without resorting to destructive testing.
There are many sources of building moisture, including humidity (during any season), condensation, pipe leaks, rain, etc. Usually a low level of moisture is fine, but leaks or heavy condensation can cause substantial defects. A thermal imaging camera cannot “see” moisture in walls, but it can detect subtle temperature differences and patterns that reveal the existence of water. In this investigation, blue shades indicate a colder surface, signifying structural dampness. Green is roughly room temperature. Shades of red display areas of inflammations, higher temperature indicating areas not significantly affected by ingress of water. .

Ferro-scan surveys are primarily utilized in mapping reinforcement details to indicate re-bar location, size and spacing.
The Principle: - The process entails measuring the disturbances created by the presence of a metallic object placed in an electromagnetic field (sinusoidal alternating current or pulsed current). When the device (elcometer) is located above an armature, it analyses the signal received and calculates concrete cover and gives an estimate on diameter of the rebars.
These measurements also make it possible to visualize the distribution of the reinforcement.

Schmidt/Rebound Hammer Tests are primarily utilized in estimating the surface hardness of concrete structures. The surface hardness is one of the key indicators on compressive strength of hardened concrete.
Schmidt hammer tests are used to estimate the strength of concrete mix. As such, the estimation of strength of concrete by rebound hammer method cannot be held to be absolutely accurate. Various references indicate that the accuracy of Schmidt hammer tests is ±20 percent. Schmidt Hammer tests can also be utilized to;

• Estimate concrete strength,.
• Provide precast quality assurance
• Measure surface strength

Ultrasonic Pulse Velocity (UPV) is used to measure the transit time of a pulse between transducers placed on the surface of a concrete element. The pulse velocity is then calculated using the measured path length through the concrete. UPV is totally non-destructive, quick to use and reflects the interior properties of concrete element. It is particularly valuable in assessing uniformity of hardened concrete. This test’s output is an indicator on relative quality of concrete. High pulse velocity readings indicate good quality concrete, the converse is true. UPV tests can be conducted using varying approaches;
a) Direct Transmission method,
b) Semi – direct Transmission method,
c) Indirect/Surface Transmission method.

Carbon-dioxide (CO2) from the air penetrates into the concrete and reacts with calcium hydro-oxide (Ca(OH)2 to form calcium carbonates. Conversion of Ca(OH)2 into CaCO3 by action of CO2 by itself is not reactive. In the presence of moisture, CO2 changes into dilute carbonic acid which attacks the reinforcement bars and also reduces alkalinity of concrete.
Using Phenolphthalein Solution to establish Carbonation Depth;
This test entails spraying phenolphthalein solution (indicator) on freshly exposed surfaces of concrete that is extracted from a structural element under investigation. The indicator will appear colourless at pH levels below 9. This indicates that the concrete has experienced carbonation and that reinforced steel is exposed to corrosion. Photo below gives a visual perspective on carbonation depth using phenolphthalein as an indicator

Crack Width Gauges are made from plastic and are used for measuring the crack width in different positions; walls, corners, floors and difference of level. Crack gauges can be utilized as follows:

• Can be used internaly or externally
• Monitors the opening or closing of cracks to an accuracy of 1mm
• Crack record cards supplied with each gaugesimplifies monitoring.
• Capable of monitoring verticle as well as horizontal movements
If need be we can facilitate long term system to monitor concrete cracks