Filter casing around your drainage tubes increases the effectiveness of your drainage investment.
The envelope material improves discharge behaviour, limits the flushing needed for the drain and extends its lifespan. Filter wrap materials are available for any type of soil.
Horman Drainagefilter offers a complete range of filter materials for wrapping tubes from a number of tube manufacturers.
Horman Drainagefilter develops and manufactures drainage envelope materials. Our product range has products for any site and any application. We can also develop a custom filter for you. After all, every type of soil requires its own individual specifications.
Voluminous filters have been applied successfully for years. This type of material replaces a layer of soil around the tube. Since voluminous filters have larger water permeability than the soil around it, this will result in a much better water discharge. Because of their size voluminous filters may contain a certain amount of soil particles. This prevents soil particles from flushing into the tubes, with all its consequences. Voluminous filters will also substantially decrease the chance of blockages caused by sedimentation of iron.
Horman offers a wide range of voluminous and thin drainage filters (geotextiles). Every filter has its own specific field of application and characteristics. The three types of voluminous filters (polypropylene, polystyrene and coconut) are placed around the drainage tube fully automatically. We even have a production line that encases tubes with diameters of up to 400mm in lengths ranging from 5 to 12 metres.
PP450
Type PP450 consists of new and recycled polypropylene fibres. The universal character of the filter allows using it for may soil types and circumstances. The O90 value is 450µm and of course the KOMO quality mark applies here too.
PP700
The use of a polypropylene filter guarantees a long lifespan. There is minimal chance of damage caused by transport or during construction with this material. PP700 has a characteristic pore size or O90 value of 700µm. With PP700 loose fibres are placed directly around the tube. With this filter, manufactured under the KOMO quality mark, there is only a slight chance of clogging the filter material. The heaviest envelope material, called “PP700 heavy” is made of non-woven material. Because of the use of new fibres, this jacket type has a highly regular structure. This quality is especially used for encasing lengths of tubes.
PS 1000
The polystyrene filter holds polystyrene granules in a net made of HDPE. The casing is very lightweight (the filter jacket for 150 metres of tubes weighs just 10kg!). With an O90 value of 1000µm, this tube is available with a filter thickness of 10 and 20mm. The available tube diameter is 60mm. The most important advantage of this type of filter is its insensitivity to micro-organisms, acids and alkalis.
Kokos 700 & Kokos 1000
Coconut filters ('kokos') are made of natural fibres. As a result this environmentally friendly material is more sensitive to certain soil circumstances than synthetic filters. However, coconut filters have been successfully used on a large scale. And there's a good reason for that. The coconut envelope materials are virtually immune to transport damage. This filter is available with typical pore sizes (O90) of 700 and 1000µm.
Thin filter materials
TYPAR
Geotextiles are manufactured by a variety of manufacturers in many versions. If requested, Horman Drainagefilter can make a filter using any type of geotextile. One standard stock item is Typar SF20, which functions best with a pore size of 225µm, if used for draining. Since the O90 value of geotextiles is usually less than 300µm, using them in soil containing ochre is not recommended.
Click here to download datasheet SF20
DRAINAGE FILTER SOCK
A filter sock for drainage applications is a circularly knit fabric of PES fibres. Loose socks are also available per kilogram for use in small quantities, so that the filter material can be put in place manually. The sock can easily be damaged during transport and installation, which is why Horman places protective foil around the tube. For this reason drainage socks are only produced on request and then delivered immediately.
