Pond construction - advantages & disadvantages of various systems
Pond liner, hard shells/prefabricated pools or tiles are often used for pool and pond constructions. An alternative to these conventional materials for pond, pool and roof coatings is offered by the "GRP coating" with glass fabric in combination with epoxy resin and/or polyurethane top coat. Such a GRP coating is not only easy to apply, but is also convincing due to its long-term advantageous properties for pond and pool construction as well as roof coatings! Below you will find detailed information on the individual materials used for a GRP coating:
What are the advantages of our PU topcoat?
The 2-component polyurethane topcoat HP-PUR-PLUS was specially developed for permanent water loads in pond and pool construction. It has a long-lasting colour stability and an excellent fullness of the paint film.
What are the advantages of GRP (glass reinforced plastic)?
"GRP" stands for "glass reinforced plastic" - a composite material made of a plastic matrix (epoxy resin) and glass fabric. The properties of GRP are particularly advantageous when building ponds and pools.
What advantages does epoxy resin offer?
Our 2-component epoxy resins are very suitable for pool, pond and roof coatings due to their properties. We have the right epoxy resin in our range for every application, both for the primer and for the GRP laminate and top coat.¬¬
You can download instructions for working with epoxy resins here:
Working with epoxy resin [PDF]
disadvantages of alternative materials:

- In retrospect, pond liners are often more expensive and more complex than initially assumed!
Pond liners with low thickness are quite inexpensive, but in the end liners with significantly higher layer thickness are usually recommended for building a pond yourself. Further costs arise from the additional reinforcement, the protective fleece/swimming pool fleece as well as root barriers and bank mats, which are not necessary with a GRP coating. Other disadvantages are the formation of wrinkles and the extremely difficult handling due to the bulky rolls of film and the time-consuming welding. In addition, flanges must be purchased to seal the connections. - Limited design possibilities in pond construction!
An ideal basis for building a pond yourself with pond liner is a simple and straight substrate that does not have any complicated geometries. The design options for the pond are therefore severely limited. In addition, wrinkles can quickly form or problems can arise when welding the pond liner. With a pond liner made of GRP, on the other hand, individual shapes and geometries can be implemented without forming wrinkles! - Pond liners are temperamental to mechanical stress!
Simple pond liners are very temperamental to external influences such as claws, beaks, stones, garden tools or toys and can therefore be damaged quickly. Necessary costly repairs are spared with a pond liner made of GRP, as it has a high level of strength and stability! - The choice of colours for pond liners is limited!
Standard PVC pond liners are only available in black, so the design options are very limited not only in terms of shape but also in terms of colour. For this reason, we recommend a GRP coating for building your own pond, where the final top layer can be designed in almost all RAL colours. In this way, individual wishes and colour ideas for the pond can be implemented without any problems!

- Transporting large hard-shell pools/prefabricated pools is difficult and cost-intensive!
Because hard-shell pools/prefabricated pools are manufactured in one piece, cost-intensive special transports are often necessary. In addition, placement in the garden is sometimes only possible with the help of a crane. The materials for a pond or pool coating with GRP, on the other hand, can be conveniently delivered by parcel service or freight forwards! - The shape of hard-shell pools/prefabricated pools is limited!
While individual wishes for the shape of the pond or pool can be taken into account when building a pond or pool yourself with a GRP coating, the choice for hard-shell pools is often limited.

- A pond coating with liquid liner often leads to leaks!
Due to the low strength, even slight stress cracks transfer to extensive coating surfaces of the pond or pool. As a result, leaks quickly form on the surface, the repair of which does not only cost nerves, but also time and money! - Liquid liner is not suitable as a simple solution for private users!
For a pond or pool coating with liquid foil, it is best to call in an expert, as experience in the field is necessary for proper waterproofing. Meanwhile, a GRP coating in the area of pool and pond construction proves to be an ideal "do-it-yourself" solution for the private user. Our GRP instructions on the subject of "How do I build a garden pond?", videos on how to build a pond yourself and the personal consulting service of our application technicians serve as assistance here.

- A pure concrete waterproofing is coarse-pored and therefore susceptible to deposits!
The deposition of microorganisms, bacteria and algae in the pores of the concrete increases the maintenance effort of the pond or pool enormously. In contrast, the pond or pool coating with GRP is characterised by its particularly smooth surface, which is less susceptible to deposits in this way! - Concrete pools are not 100% waterproof!
Especially in pond and pool construction, the materials are exposed to a high continuous water load. Since concrete is not 100% waterproof after intensive processing, water can penetrate in small amounts over time. This causes stress cracks to form in the concrete or in the applied tiles. A GRP coating, on the other hand, meets the requirements for high exposure to water and is therefore ideal for long-lasting pond and pool projects.

- Polyester resins may not be shipped to private customers!
Due to an amendment in the Chemicals Prohibition Order, the shipment of polyester resins to private customers is prohibited due to certain chemical substances. - Polyester resins must not be processed under sunlight!
For larger projects in pond and pool construction, elaborate sun protection constructions must be built in order to process polyester resins without problems. With polyester resins, the sunbeams or UV rays interfere with the curing process on the surface. Epoxy resins, on the other hand, can be processed under sunlight without any problems and are therefore more suitable for building pools and ponds yourself than polyester resins. - The processing of glass mats is very time-consuming and a lot of resin is used!
Glass mats are not only difficult to process, but also have a very high resin consumption, so that additional costs are incurred for the pool or pond coating. In addition, this structure must be treated further (sanding, sealing), as individual fibres stand up during processing. If this is done incorrectly, damage such as osmosis can occur, which does not occur with a coating of epoxy resin and glass fabric.