Waterproofing liners: Firestone PondGard, PondEasy, GeoGard and GeoSmart EPDM

EPDM membranes

The best choice

Firestone PondGard™, PondEasy, GeoGard™ and GeoSmart EPDM are rubber panels with high performances,  the benefits are recognized by installers, professional landscapers and architects worldwide.

Ease in installation

The installation of these products is easy, considering that the material is lightweight, easy to position and available in a variety of measures without joint (widths up to 15.25 m and lengths up to 61 m).
For the construction of large water bassins, more than one Firestone PondGard™ EPDM panels can be installed on site joining them with the self vulcanizing double-sided adhesive Firestone Quick Seam ™ Tape. Are not required special tools or specialized personnel.

High flexibility

These liners are highly flexible at low temperatures (down to -45 ° C), allowing installation in any time of the year. Adapting perfectly to the different conformations of the banks, Firestone PondGard ™ EPDM liner allows great creativity and allows you to make even the most demanding installations.

High elasticity

The liner has an excellent elongation capability that allows it to adapt to the performance of the laying surfaces. This feature is important when of the pond is filled up, when the possible subsidence of the land, the hydraulic load or erosions could cause tensions of the membrane.


The Firestone EPDM rubber has been specially designed to be safe for the life of fish and aquatic plants. This guarantee is confirmed by a special marking on the membrane that certifies its non-toxicity.
Being a highly stable membrane, Firestone PondGard ™ EPDM liner resists to algae and microorganisms that are part of a healthy ecosystem of natural pond. Moreover, the Firestone Building Products facilities have received an ISO 14001 certification for their environmental management system.

Extreme durability

The Firestone EPDM rubber provides exceptional resistance to UV light, ozone, frost, snow, and extreme temperatures. Our liner does not contain plasticizers that migrating could cause cracks or breaks and thus has extraordinary durability: even after over two decades of service, the forms of water built with Firestone PondGard ™ EPDM liners are functional and beautiful as the first day of installation.

Firestone: more than a century of experience

The Firestone EPDM liner is developed by Firestone, a leader in the rubber industry. Since the beginning of 1900, Firestone has served its customers with rubber products designed for optimal performance and long life. This tradition of quality has extended to the market of the pond through the Firestone Building Products, a leading global manufacturer of waterproofing rubber membranes.

The quality of the pond begins from the bottom

Today everyone can passionate in water gardening; and to be able to enjoy this lifestyle, the choice of waterproofing material is of vital importance. This non-toxic membrane with exceptional durability has been successfully installed in thousands of applications around the world for various uses:
Decorative ponds Lakes for golf courses Watercourses Glass-like ponds
Koi carp ponds Lakes Wetland systems Waterfalls
Natural pools and swimming ponds Fountains Snowmaking tanks Water collection tanks
Sport fishing lakes Irrigation canals Landfills covers Rivers, streams and canals
We advise you to pay close attention to who sells liners for ponds with super promotions, because the liners too cheap are suspicious and often not suitable for applications related to the lakes. Also avoid buying EPDM liners for roofs, as they are often toxic (sometimes very toxic) to plants and aquatic animals.

Reduced maintenance

The Firestone EPDM rubber membrane, once installed, requires a minimal or null maintenance and remain functional for long time. In case of damage, the Firestone EPDM liner is easy to be fixed in place.

The pleasures of a water garden

Making a pond in your garden will undoubtedly have a beneficial effect on the quality of your life: watching fish and frogs, touching the surface of the water, smelling the scent of water lilies in bloom, relaxing thanks to the sound of the gurgling of water, and enjoying your natural pool with family and friends.
The pleasure of a water garden will improve your habitat and will increase the value of your home!

How to calculate the amount of liner

In order to calculate the amount of liner required to achieve your pond you can use the following formula:
Liner length = pond length + 2 x depth + 2 x 1 m (for anchoring the liner on the bank)
Liner width = pond width + 2 x depth + 2 x 1 m (for anchoring the liner on the bank)
Ex. 6 m long pond 4 m wide and 1.5 m deep.
Liner length = 6+(2 x 1,5)+2 = 11 m
Liner width = 4+(2 x 1,5)+2 = 9 m (for pond with rectangular plan)

Installation procedure

Make the excavation with the desired shape and with sloped edges inward.
Dig deeper areas (about 80 cm to 100 cm for small ponds and lakes deepest) and shallow areas (about 25 cm) for plants.
Eliminate each stone or root and spread a layer of sand on the bottom of the pond.
It is strongly recommended to pose a substrate of nonwoven geotextile as anti-puncturing for the membrane.
Spread into place the Firestone PondGard ™ EPDM membrane, unrolling it carefully into the pond without drag to avoid damages against pointed or sharp objects.
Hold in place the membrane stabilizing the edges, only in some places, with brick or stone with flat surface.
Gradually enter the water into the pond, bending and placing the membrane in order to give a neat appearance. With the increase of the water level, the membrane initially will stretch and then slide inwards, adapting to the shape of the excavation (if the ballast at the edges was too heavy, so as to prevent the sliding of the membrane, this must be lightened).
Cut with scissors the excess material, leaving around the perimeter of the pond a border of the membrane sufficient for its anchoring to the ground.
The membrane can be concealed, and at the same time anchored to the edges well leveled with the same heavy elements provided for finishing (rounded stones, bricks, etc.).

Why a black liner?

The black color of the EPDM Firestone liners depends from one of the components of the mixture optimized by Firestone for the realization of its products.
This component (carbon black), while having predominantly technical value, ensures aesthetic results superior to colored liners:
1.  protects the rubber from the UV rays and ensures extraordinary longevity even when directly exposed to the sun
2. properties of resistance to wear, traction, friction and abrasion are improved
3. the stability of the formulation ensures that no harmful substances are released for swimmers, fish or plants
4. the color of dark background creates the mirror effect of water and makes sure that the environment is reflected in the lake
5. the dark color turns out neutral during colonization by aquatic microorganisms ensuring an aesthetic effect always pleasant (the liner after a few months of installation assumes natural colors ranging from green to blue to gray).


Technical specifications

  • Colour: black (see footnote)
  • Thickness: 0,80 mm (PondEasy) - 1 mm (PondGard) - 1,1 mm (GeoGard) - 1,2 mm (GeoSmart) - 1,5 mm (GeoGard and GeoSmart)
  • Weight: 0,80 Kg/mq (PondEasy) - 1,25 Kg/mq (PondGard) - 1,41 Kg/mq (GeoGard) - 1,2 Kg/mq (GeoSmart 1,2)  - 1,9 Kg/mq (GeoGard 1,5) - 1,5 Kg/mq (GeoSmart 1,5)
  • Length: 30,50 m and 61 m
    (the closed coils are long at least 3,30 m)
  • High quality material
  • High extension: more than 300%
  • Flexibility at low temperature until -45° C
  • Great softness even at low temperatures
  • Resistant to thermal shocks up to 250 ° C
  • UV rays resistant
  • Ozone resistant
  • Exceptional life span
  • Ecologic
  • Non-toxic to fish and plants
  • Does not rot
  • Roots resistant (DIN 4062)
  • Contains no softeners

CE certifications obtained

N° EN13361:2004 - Construction of water reservoirs and dams.
N° EN13362:2005 - Construction of canals.
N° EN13492:2004 - Construction of liquid waste disposal sites, transfer stations or secondary containment.
N° EN13493:2005 - Construction of solid waste storage and disposal sites.
Quality Management Certification ISO 9001 (FM 32845)
Environmental Management Certification ISO 14001 (EMS 52644)

2D custom-made EPDM panels

It is possible to order 1 o 1,20 mm thick EPDM panels custom-made up to 2000 m2 in one piece.
Example: 60x30 m.

3D custom-made EPDM panels

It is possible to order 1 o 1,20 mm thick EPDM panels custom-made in one piece in 3D.
In this way, when there are formal and well-defined walls, it is possible to have a piece of membrane specially prepared so as to speed up the processing and installation on site.

EPDM: a record product

EPDM is an acronym for:

EPDM rubber is a terpolymer of the three monomers: ethylene, propylene and a diene-component.
EPDM rubber is the main material of the polymeric geomembranes of low permeability, manufactured by Firestone Building Inc. for over 40 years. 
A chemical structure to indicate so:  
Struttura chimica

The EPDM rubber, once released by the industrial production is an ELASTOMER, that is a thermosetting, a product that once vulcanized (cooked over 180 ° C) is ready to be used. (see below)

The final elasticity is due to the cross-links between different polymer chains that give a memory to the product. In practice, they promote the elastic deformation, "forcing" the chains to return to the state before deformation.

From Wikipedia (italian site)

The generic term of elastomer indicates the natural or synthetic substances which have the chemical and physical properties typical of the caucciù (or natural rubber); its most distinctive feature is the ability to endure large elastic deformations: for example, it can be stretched different times taking its size again once recreated a situation of rest. 
The elastomers are molded into the desired shape by extrusion or hot forging.

The elastomers are part of the polymers and are divided into two main classes: 
    •    thermoplastic elastomers
    •    thermoset elastomers

The thermoset elastomers are produced by linking to each other the polymer chains through the use of chemical reagents, temperature and pressure in a process generally called vulcanization. This change in structure imply the appearance of the thermosetting properties: it is impossible to remodel them once the vulcanization has occurred.

Deformation process of an elastomer. (A) is an unstressed polymer; (B) is the same polymer under stress. When the stress is removed, it will return to the A configuration. (The dots represent cross-links).
Initially, it is a product that comes from the chemical industry in the form of white little balls; thanks to the contribution of other products (each of which introduces the characteristics of the final product), it becomes a waterproof sheet. 
Here a semplification of the production process, with the additives useful to create the final product with its qualifying characteristics:

il make-up chimico
The final characteristics of the product are:
Superior physical properties 
Resistance to aging and UV rays 
High flexibility at low temperatures 
Dimensional stability 
Easy to install.

The final sizes of EPDM membranes are determined by the dimensions of industrial machineries.
The biggest membrane is 15,25 x 61 mt, otherwise, the smallest one has dimensions of 4,27 x 30,50 mt.
The Firestone EPDM membranes are commercialized with two different thikness: 
- 1,02 mm (1,25 Kg/mq)
- 1,14 mm (1,41 Kg/mq)

The membrane can be jointed thanks to double-side tapes, and it can be installed in very extreme conditions of temperature: ranging from -30° C (like Siberia) to 40° C (Arab countries). 

Details for the correct installation of the membrane are present in the documentary section.