DAMAGE RESULTING FROM CONDENSATIONS £ Billions are lost each year through damage and litigation

Condensation the destroyer Condensation on some materials provides ideal conditions for mould growth.   Condensation wets insulation causing coldbridging and loss of thermal insulation.   Condensation induces metal corrosion in and outside cavities.   Condensation dripping damages machinery and products.   Condensation dripping from car park roofs, Railway platform canopies can freeze causing dangerous underfoot conditions.

Example Unheated building temperature + 12°C, 80% RH How much can the temperature decrease (e.g. during the night) before condensation occurs ? You proceed from the temperature scale (12°)until 80% humidity curve is reached and continue vertically down to the 100% curve and back to the curve indicating the temperature. Temperature +9°C is the dew point. In this case condensation starts when the temperature has decreased 3°

WHAT IS CONDENSATION ??
Air is a mixture of gasses. There is always vapour in the air, and there is more of it when the temperature is high. When the vapour meets a old surface it condenses into water. Condensation always occurs when the surface temperature is down to and below the so called dew point.
In uninsulated buildings condensation occurs during quick changes in weather. The surface temperature of a steel roof may due to rain or heat radiation during the night call to as much as 5°C below the inside temperature.
These circumstances do not usually last long. The problems caused by condensation can easily be prevented by Grafo-Therm anti-condensation coating.
WHEN DOES CONDENSATION OCCUR ??
Condensation is a problem especially in unheated buildings, uninsulated roofs, open roofs, etc. In insulated buildings condensation is usually prevented by a sufficient layer of insulation, so the surface temperature does not fall to or below Dewpoint.
However, it is possible for condensation to form in some insulated roof constructions, if an air gap exists between the top of the insulation and the bottom of the top sheet, as exists in many 'double skin' roof constructions. This air gap draws in moist air in certain climatic conditions and this air can condense on the underside of the top sheet, forming condensation droplets. Grafo-Therm anti-condensation coating applied to the underside of the top sheet prevents this.

The 'Grafo-Therm' treatment. How does it work. In the dry state Grafo-Therm is an efficient thermal insulant, albeit that a 1.5mm thickness would not be efficient against heat loss, it does put back the time before dewpoint occurs, considerably reducing the periods during which condensation forms. Thereby naturally reducing the amount of condensation formed during any one 24 period. Whenever dewpoint is reached on the surface coated, condensation will form and this will immediately be absorbed by the coating. A 1.5mm thickness can absorb and control against dripping up to 1.0 litre of moisture per M². Having absorbed moisture it is most important to effect rapid evaporation and removal from the cavity when conditions change to drying. For this Grafo-Therm is superb, for example, when sprayed onto a 1000M² corrugated roof the textured finish of the compound effectively increases the specific drying surface by at least 10 times = 10,000M², on most corrugated sheets this can increase by 20% to allow for the corrugations = 12,000M² of drying surface. Grafo-Therm having proven absorption and capillary capabilities assures maximum benefit from this large specific drying surface, enabling fast and efficient cyclic drying. The release properties of Grafo-Therm are faster per thickness and area than competitive materials which rely on greater thickness being applied.

For full Technical Specifications of Grafo-Therm see pages 1-6 below Page 1  This is Page 2  Page 3  Page 4  Page 5  Page 6
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Manufactured by Grafo Products Limited

Sales Office - Rosemount, Broadway, Upper Holton, Halesworth, Suffolk, IP19 8QN.
Tel: 01986 873127 Fax:01986 872850 Email:grafo@grafoproducts.fsnet.co.uk