Our systems are water permeable and contribute to environmental protection.

This is how it works

Grainsize is the deciding factor! A synthetic resin pavement fixing mortar is always made of two components. The first component is binding agent, which is responsible for hardening and stability.

The other component is the filler material, which is responsible for water permeability. The filler material component is a washed, firedried quartz sand with various grainsizes.

The quartz sands have no zero components, unlike cement (cement dust). These means that hollow areas can form, through which water can seep. The size of the hollow areas, which depends on the grainsize, determines the degree of water permeability. Especially during winter, the advantage of large hollow areas is evident. Water, that is still in the joints during ground frost, freezes and is able to expand into the hollow areas. This means cracks and breakage in the joints is avoided.

The capillary effect

Capillarity or the capillary effect is the way liquids react when they come into contact with capillaries i.e. tight pipes, cracks or hollow areas in hard materials. Example: if you dip a glass tube vertically into water, the water will rise slightly in the tube against gravity. This effect occurs due to surface tension of the liquids themselves and from the border surface tension of the liquids with the hard surface (in this example: glass).

In the construction industry, when synthetic resin bound paving joint mortar is used i.e. on paved stone surfaces that have been jointed with synthetic resin based paving joint mortar, the capillary effect can be seen in the joints, because depending on the jointing mortar used and the pore content or sand grainsize, varying amounts of moisture are able to rise against gravity. This means that even if a foundation is only slightly water permeable, water will not remain permanently in the joint.

Using ROMEX® systems, you can do your part to be environmentally friendly. Because the ROMEX® products strengthen surfaces, paths and squares, without sealing them!

Coefficient of permeability

In Geotechnology, permeability is used to quantify the permeability of ground and rock for liquids or gases (i.e. groundwater, crude oil, natural gas).

A calculated value that quantifies the permeability of water through ground or rock, is called the coefficent of permeability or hydraulic conductivity value.

Water permeabilty acc. to DIN 18130:

  • very highly permeable from 10-2 m/s
  • highly permeable 10-2 up to 10-4 m/s
  • permeable 10-4 up to 10-6 m/s
  • slightly permeable 10-6 up to 10-8 m/s
  • very slightly permeable below 10-8 m/s

Overview of ROMEX® paving joint mortars