Water Column
Eureka's Water column - less can be more!
Water column expresses the coating, which is being used for making the nylon and polyester tents waterproof. For example: 1000 mm, means that there can be 1000 mm water pressure per 1 cm² on the tent fabric, before it starts leaking through. From 800 mm on the material can really be called waterproof. It's better to have a higher value, because there is a possibility that the coating wears out and the value decreases. There is no standard for water colomn testing. Eureka! measures after production, however some brands mention a value “off the roll” or before production, which of course is much higher.
For most of Eureka! tents we use PU coating; this is the strongest and most resistant to abrasion kind of coating. However, higher value of the water column has a backside: the strength of the fabric will decrease because the chemical components of the coating are weakening the fabric fibres. Therefore the right combination of amount coating / strength fabric is very important for the best result.
Water column can not be used as a waterproof value for the fabric of Technical Cotton and 100% Nature Cotton, because these fabrics have a different way of sealing. Cotton fabrics are impregnated so that they are waterproof and breathable. Cotton swells if it gets wet and seals up in that way. Technical cotton needs little coating (1000 mm), because it contains 35% cotton and the swelling of the cotton helps to become waterproof.
All Eureka! tents have been studied carefully to get to the best waterproof / strength fabric ratio. Please note there are no general norms and checks for the water column value on the market. Eureka! gives honest information, on which you can rely.
