The Difference between Shotcrete and Fiberglass Artificial Rock

Artificial rock can be created from several different types of materials, including fiberglass and shotcrete. While both are durable and lightweight, there are some differences between the two which should be taken into consideration when choosing artificial rocks for your yard.

Advantages of Fiberglass Artificial Rock

Fiberglass is a very light and durable material, which are two advantages for artificial rocks. It is resistant to water and the elements, making it a good choice for water features such as waterfalls and ponds. Fiberglass artificial rocks are available in either molded for hand-sculpted models, and they can either be solid or hollow, which will allow them to be used to hide unsightly yard elements such as pipes, electrical boxes and pumps. Hollow fiberglass rocks are quite light, but even solid molded fiberglass rocks are light in weight.

Disadvantages of Fiberglass Artificial Rock

For those who wish to make their own artificial rock, fiberglass can be messy and difficult to work with. The very light weight of fiberglass, although often a benefit for artificial rocks, can be a little too light in some applications, especially when using hollow rocks in areas that are prone to high winds. Although realistic looking fiberglass rocks are available, some people feel that concrete makes a more realistic finish, due to the inherent shininess of fiberglass, which isn't a natural look for rock.

Advantages of Shotcrete Artificial Rock

Concrete artificial rocks, especially those which are of high quality, can often be difficult to distinguish from real rocks. The surface can be textured and painted to closely resemble the surface of genuine rock, especially when there are little crannies and nooks created in the surface. Moss and lichen will readily grow on shotcrete rocks, adding to the realism of the artificial rocks. Shotcrete can be applied over other surfaces, producing solid artificial rocks, or over molds to produce hollow models. Artificial rocks and rock surfaces created using shotcrete are lighter than real rocks, with hollow models being useful for hiding objects such as pipes, pumps and electrical boxes. The materials used to create these types of rocks are quite durable, and pigments and colorants are often added to the concrete mixture, allowing a solid color throughout in addition to pigments and stains that are added to the surface. When used to create artificial rock walls, shotcrete can also be combined with other materials such as polystyrene insulation to provide a surface that is not only durable but also insulated. Other types of materials can also be added to provide a more realistic finish. An applied layer of shotcrete can also be textured with a trowel or other tools to create a rock-like finish.

Disadvantages of Shotcrete Artificial Rock

Shotcrete is usually applied as a somewhat thin layer over other types of surfaces, so the strength of shotcrete artificial rocks is usually somewhat dependent on the structure it is applied to. Just as with any type of concrete product, artificial rocks made with shotcrete need to have their surface sealed to prevent water absorption and damage from the elements. Applying shotcrete is a skill generally reserved for professionals, so those who wish to make their own artificial rocks would probably be better off using ordinary concrete over molds and support structures.

Mr. Peter Heiss and Mr. Mark MacIsaac - are the preeminent designers in the Pacific Northwest and have spent a lifetime studying and emulating all of nature's beauty. We can create pools, hot tubs, waterfalls and every other feature out of any rock you choose. At Raincity Rock & Waterscapes