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              DAMP SURVEYS

                Thermal Imaging Damp Surveys                                 NDT LISTED BUILDINGS     Damp, Condensation, Water Leaks, basements, floors, roofs      Horton Levi damp detection surveys include in-depth physical      inspections, endoscopic intrusive investigations, where required,      and infra-red scanning of walls and roofs as appropriate.      Comprehensive investigations are also available and can include      some or all of the following services: Infrared Thermography to identify moisture / heat loss Insulation Integrity Data Logging - Relative Humidity, Temerature, Co2 Radio Frequency metering for sub-surface moisture detection Electromagnetic inspections to ‘map’ and trace damp. Endoscopic Video inspections
Thermal image over photograph. The thermal data provides a visualisation of the extent of the damp and spread via the ceiling.
   Black, Mauve and dark Blue areas are moisture densities    respectively
Damp corner and floor / wall junction
Damp, Relative Humidity and Mould
Relative Humidity is usually measured as a percentage of water vapour in the air. The amount of vapour contained in the air can vary with air temperature and pressure. Comfort Level, Effect of Humidity The effective ‘comfort level’ in a home or office can vary with temperature and humidity. Below about 14° C, humidity has little effect on temperature feel but at normal house / office heated temperatures of about 22°C, there can be a significant difference in ‘comfort level’. When humidity is low, a normally warm temperature can feel cool owing to faster evaporation of body perspiration. Conversely, in higher humidity situations, perspiration is slowed providing a warmer feel at the same temperature. Many materials (wood, plaster, decorative / paintings etc) absorb water vapour from the air. Materials will therefore absorb more moisture in high humidity situations and release moisture as the humidity lowers. Moisture soaked plaster or plasterboard can in some cases damage paintings, clocks, musical instruments, building components etc.Further effects and consequences of high humidity is condensation behind plasterboard walls that can result in structural damage and can provide perfect conditions for the growth of mould and mildew. Ideally during the winter months an office should be about 22°C with a relative humidity between 30 and 60 percent. During the summer months, an indoor temperature of about 20°C with a relative humidity (UK) between 40 to 60 percent is considered normal.
High density damp either side of the window. Moisture is at ceiling level and is clearly travelling down from the above floor or the parapet wall.
Light Blue is showing a water saturated parapet wall. The moisture can be seen spreading down the wall past the DPC and has saturated the inner wall of the flat below.
Exhausting air from rooms like toilets, cafeterias and other areas without replacing it, creates a negative pressure that can draw unconditioned air through exterior walls, windows and doors. As the outside air is drawn into a building by the negative pressure that is created by air movement or exhausts, the moisture in the air may condense when it comes in contact with the cooler surfaces. The condensation provides the moisture fungi required for growth. The image to the left shows an example of this. The Black and Mauve is dense moisture in the ceiling and wall.
Damp Surveys