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Permeable Paving Systems

Natural Stone Permeable Paving System

Permeable paving systems are getting a lot of attention and are becoming a part of construction codes in many areas recognizing the need for innovative storm water management measures.

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Permeable Paving SystemsLow impact, sustainable permeable paving systems (SPPS) have been used throughout Europe for decades showing that it is a valuable solution, when done correctly, with the best materials and utilizing the right applications! Costly limitations have been addressed, creating strong values and lasting durability. Borrowing from the past and reaching into the future it is now possible to have exceptional and sustainable permeable paving offering high performance for light, medium and high traffic loads!

Three ingredients of a successful system are:

  1. A design that includes an engineered sub-straight allowing for proper drainage with an overflow outlet
  2. High density paving stones with low porosity and rough but straight edges to help with interlock. The most sought after stone pavers are a type of granite called Porphyry
  3. Permeable sanded epoxy jointing mortar designed specifically for different traffic densities and road conditions. The leader in this industry is the GftK line of vdw jointing mortars with manufacturing facilities in Germany.

The many projects in Norway, Sweden and Denmark and busy city streets in England, France and Germany and more are examples of this proven success in the toughest climates and high traffic roadways.

This system is:

  • Fast, durable & cost effective
  • Can be installed in wet conditions at low temperatures
  • Mechanical sweeper resistant
  • Excellent abrasion resistant
  • Frost and de-icing salt resistant
  • Environmentally friendly

The primary purpose in the design of a permeable paving system is to effectively reduce and manage the quantity of surface rain water runoff while accommodating pedestrians, vehicular parking and traffic. A full filtration system designed for permeable subsurface soils should allow the storm water to penetrate the surface and filter through the base course and the native soils back into the aquifers while promoting tree and plant survival by providing air and water to the roots.

Partial Filtration

If the capacity of the soil to filtrate the water is exceeded, the base may be designed to filter, partially treat and slowly release the water into a storm sewer.

The benefits include a more beautiful, user friendly environment that eliminates surface retention ponds and can reduce runoff up to 80% from storms drastically reducing pooling and flooding on parking lots. Aggressive permeability can also contribute to faster snow and ice melt drainage.

We found products that fit this equation both independently and in a combined system to create a sustainable solution for modern permeable paver applications.

Porphyry paving stones and GftK jointing mortars

Porphyry paving stones and GftK jointing mortars


Porphyry Pavers

Porphyry Pavers

Porphyry is chosen for its beauty, function, and durability.  Porphyry is an ideal paving material for residential, commercial, civic and hospitality applications such as streets, sidewalks, plazas, parks, patios, and driveways. Available in many sizes from cubes to pavers, Porphyry lends itself to an old world, hand-crafted look while meeting modern standards.

Porphyry is:

  • Denser and less porous than most granites
  • Unaffected by freezing and thawing
  • Highly resistant to chemicals
  • Extremely durable requiring little maintenance
  • In compliance with ADA requirements for smoothness and slip resistance when set correctly
  • Can be set on concrete for a rigid application or over an engineered base course of gravels and sand for a flexible, permeable application.
  • Proven over the millennia to be a superb, sustainable road surface material
Porphyry in public, heavy traffic spaces can be highly effective.

Porphyry Paving in public, heavy traffic spaces can be highly effective.

Jointing Mortar

Since the company’s formation in 1971 GftK GmbH Germany has been pioneering the development of innovative epoxy resin-based mortar systems (EP-mortar). They set a milestone in 1985 with the launch of their first EP pavement fixing mortar as a simple, fast, inexpensive, environmentally compatible and durable option for permeable unit paving projects.

GftK Jointing MortarGftK’s epoxy resin-based jointing mortars bring a proven record of bonding, strength and durability as the highest value for permeable paving solutions. The products are specifically designed for the type of natural stone or manufactured paving, for the format of the paver and the type of traffic and exposure anticipated.

When planning to use GftK sanded epoxy jointing mortars for a project design, consideration for which type to use should include the following:

  • Type of Paved Area – residential, commercial, urban sidewalks, streets, & parking areas
  • Paved Area’s Traffic Exposure – pedestrian use, light, medium or heavy vehicular use & heavy commercial traffic
  • Paved Area’s Environmental Exposure – Mechanical or street sweepers, water jets, ice melt & weed or insect prevention, requirements for permeability
  • Size and Type of Unit Pavers – Small Format Pavers including cubes & cobbles which are regarded as joint dependent or Large Format Paving slabs & flagstone which are considered bedding dependent along with the surface profile, mortar color and sensitivity to grout staining.
  • Installation Conditions – anticipated wet weather, residual moisture, high or low temperature variations & restrictions on dust or waste run-off.
  • Specific Joint Dimensions – Joint depth, joint width and the variations of these across the finished area.

GftK Logo

GftK vdw 800

  • High performance permeable grout
  • Light traffic loads
  • Water permeable (1.5 gallons / sf / min)
  • Low Temperature application: 44.6 degrees
  • Fast, durable and cost effective
  • Easily flow applied
  • Self-compacting
  • Can be applied on wet surfaces
  • Optimum strength correlation
  • Mechanical sweeper resistant
  • Abrasion resistant
  • Frost de-icing salt resistant
  • No weeds or boring insects
  • Environmentally friendly

GftK vdw 850

  • High performance permeable grout for small format paving
  • Medium to High traffic loads
  • Water permeable (5.6 fl oz / sf / min)
  • Low Temperature application: 37degrees
  • Fast, durable and cost effective
  • Easily flow applied
  • Self-compacting
  • Can be applied on wet surfaces
  • Optimum strength correlation
  • Mechanical sweeper resistant
  • Abrasion resistant
  • Frost de-icing salt resistant
  • No weeds or boring insects
  • Environmentally friendly


Drawing upon the knowledge and experience of Porphyry and permeable systems expert’s world wide, Milestone Imports has established guidelines, specifications and instructions for design, application and installation.

Milestone Imports
Quality, unique stone solutions
Creating excellent value

Permeable Paving Systems in commercial districts