PERFORMANCE SPECIFICATION

GLASS REINFORCED POLYESTER (GRP)

1                   Physical Characteristics

1.1                Glass Reinforced Polyester (GRP) is hard, strong, resilient and resistant to mechanical damage.  It is weather resistant and is suitable for both internal and external use.

2.                  Composition and manufacture

2.1                GRP consists of two elements : a suitable polyester resin and a reinforcing matrix of glass fibres; the glass fibres may be in the form of chopped strand matt, tissue, etc., according to the application.

The resin is cured by the addition of a chemical catalyst; the curing process is exothermic and no additional heat is required.

The fire retardant properties of the material may be improved by the use of inert fillers in conjunction with fire retardant grades of the resin.

3                   Structural Characteristics

3.1                In strength to weight ratio, GRP is superior to mild steel : it is a hard rigid material, resistant to physical damage.

GRP mouldings are normally self supporting from point fixings without the need for additional reinforcement.

Mouldings are dimensionally stable and are not liable to sag or warp.

4                   Fire Propagation

4.1               GRP mouldings have a Class 3 rating for surface spread of flame as defined in BS476 Part A : 1970 (1984).  By specifying the use of flame retardant resins and inert fillers or other additives, a Class 2 or Class 1 surface  can be achieved, as defined in the Building Regulations 1991.

5                   Effects of Liquids

5.1               GRP is generally resistant to atmospheric moisture and to the chemicals and chemical vapours normally encountered in internal environments.

The material however, should not be used in situations where there is any risk of contact with strong organic solvents or solvent vapours, since these are liable to cause deterioration of the resin and subsequent loss of strength.

Provided the fixings are adequately protected, GRP mouldings may be installed in aggressive  atmospheres, even those that are heavily charged with chlorine, such as swimming pools.

6                    Thermal Properties

6.1                 Thermal co-efficient of expansion is approximately 3 x 10 per °c.

Maximum service temperature is 43°c specific U values can be achieved by the use of sandwich construction.

7                    Light Transmission

7.1                The light transmission rate of unpigmented mouldings is up to 70%.

8                    Biological Properties

8.1                GRP is rot proof and will not generally support the growth of fungi, moulds or bacteria.  It is inorganic and immune to insect and vermin attack.

9                    Compatibility

9.1                 GRP can be used with all normal building materials.

10                  Durability

10.1               Provided that GRP mouldings are securely fixed and not damaged during fixing, they offer a life in use of at least 30 years.

11                  Workability

11.1               GRP mouldings are easily cut or drilled on site and are simply fixed to the structure by screws and plugs or suitable fastenings from a purpose made steel suspension system.

The surface provided it is etch primed will accept any oil based decorative paint.

12                 Health & Safety

12.1            GRP is inert and presents no risk to users at any stage of the construction process.  No special protective clothing is required during its fixing or maintenance.