Over a period of more than 20 years in the GRP roofing and architectural features industry, there have been many advances in the manufacturing process and use of GRP within the construction sector.
An abbreviation for ‘glass reinforced polyester’, GRP is a light, durable and astonishingly tough constructional material which can be molded and fabricated into all manner of products. GRP is a composite of a resilient durable resin with an immensely strong fibrous glass. Polyester resin is the main component and just as concrete may be reinforced with steel rods polyester resins may be reinforced with glass fibers to form GRP. The benefits of a very strong and light weight construction material are particularly relevant when designing and manufacturing structures and roofing features.
GRP has opened up many new avenues for Architects and creative designers, its unique physical properties allow it to be easily tooled, molded and manufactured to meet almost any specification. The final finish can be made to emulate any number of naturally occurring surfaces, such as timber, tile, stone or lead and because there are few constraints on size, shape, colour or finish, this can deliver great design and appearance whilst being cost effective.
One example of this is the traditional clock tower. When manufactured in GRP one side is first hand crafted in Ash timber from which a mold tool is produced. The mold is coated with a release agent before a very durable polyester gel coat is applied and allowed to cure before reinforcing with layers of glass mat impregnated with polyester resin to achieve the required thickness. When cured the laminate is extracted from the mold and the process is then repeated. The components are then joined together to complete the body of the clock tower.
Ash timber is used for the original pattern to ensure the finished product has a beautiful realistic wood grain. Likewise one side of a roof is first dressed in lead over a timber pattern, a mold produced and four sides manufactured to give the finished product an authentic traditional appearance of a genuine lead roof but without the high cost and weight of the real materials. Another benefit of using GRP over traditional materials is that the molds can then be cleaned and reused many times over enabling identical units to be produced and in a very short space of time.
GRP is also very strong and has almost seven times the flexible strength of steel but is extremely lightweight, which makes installation much simpler than its traditional material counterparts, saving costs and helping to reduce Health and Safety issues on site. GRP structures also have an exceedingly long life span with low maintenance requirements and in a half-century of composite development, well designed GRP structures have yet to wear out.
GRP is non-corrosive and has a much longer life expectancy when compared to a variety of other construction materials. In highly corrosive environments it is the perfect choice over metal, wood, or plastic. A popular choice where exposure to harsh environments is a concern, GRP can provide resistance to ultra violet light, salt air, and a variety of chemicals and because it is chemically inert and corrosion-resistant it offers an economical alternative to stainless steel. It also offers high levels of water resistance and will not buckle or distort in high temperatures.
An amazing level of detail can be given to the molding ensuring that the original style, surface finishes, colour and even aging effects are maintained. The greatest advantage of GRP over conventional materials however is the ability to design and build large structures conceived as a whole and not as an assembly of parts which have to be jointed together. For example a 5m diameter dome requires none of the conventional support structure inside the building, enabling a large open area within the building and space directly beneath the dome. The self supporting structure can also be easily lifted into position and installed using minimum man power and a crane within only a few hours.
So not only does GRP save time and money in the construction of the roofing feature, it reduces installation costs and ongoing maintenance fees too, making it an excellent cost effective roofing material for today and the future.
Source by Protechwood