There is no meaningful difference between the two kinds of resins in their applications. However, some experts believe that polyester resin makes continuous low level chemical reactions with possible continuous light smell in closed spaces. They prefer to use polyester-resin-coated panels in open spaces and use epoxy-resin-coated ones in closed spaces. Composite panels coated with polyester resin are cheaper than the epoxy coated ones (Polyester is a domestic product while epoxy is imported). Although several experiments have proved that there was no such smell at homes decorated with polyester-coated wooden furniture; but some people might be sensitive to it and so prefer to use panels coated with epoxy resin instead. Please refer to “resin” part in the Technical Specifications section of the site for further details. It is worth knowing that using epoxy resin instead of polyester enhances the rigidity of composites and improves its chemical resistance against acids and alkali.

It was around 1990 that the ability of such a structure material was proved to hold the tension and bending loads. Initially, these structures were made by hand and could not be manufactured at the industrial level. The industrial production of fiberglass fabrics as well as reinforced composite panels was achieved almost 10 years later in 2000.

The fiberglass part of the composite panels is fireproof, but the resin (epoxy or polyester) gets flamed when exposed to fire.
Whereas the panels are used as ceiling/floor in a way that are covered with a 3-centimeter concrete over which is a floor covering of stone, ceramics or granite; and under which is a false ceiling of plates at a distance of almost 30 centimeters (a metal network in which are gypsum plates); then the flame cannot reach these panels in any directions (According to the experiments, if the building structure profile-covered with a 2.5 centimeter concrete-is heated up to 1000 degrees Centigrade, it takes one hour until the profile temperature reaches 500 degrees Centigrade). Therefore we do not need to use a fireproof version of these panels. However, if we want to make these panels fireproof as well, the following two methods should be used:
a) Adding self-extinguishing materials into the resins when the fiberglass fabrics are being saturated with resin. Among these self-extinguishing materials is Magnesium Hydroxide (and in some cases Aluminum Hydroxide); which increases the flammability temperature threshold while extinguishing the panels by releasing vapors of water (a safe gas).

b) Applying anti-fire coating paint on the panel surfaces, which protects the panels against direct flame. The following pictures display the effect of fire on anti-fire painted panels after being exposed to fire for 10 minutes.

If it is required to have these panels exposed closely to fire and for a long time,

it would be better to cover them with concrete (with even 1 centimeter thickness) and the space between the 2 layers of the composite panels to be filled with gypsum and/or concrete in order to make them resistant against fire as well as suppleness. This experiment has been done in practice.

No. Strength of the panels, their load and shock bearing resistance, are connected with the tension bearing characteristics of the woven fiberglass fabrics and not the resins. The resin just provides the panels with stiffness and the required spacer between the two surfaces of the fabrics; as to put the lower surface of the composite panel under tension state when the pressure is exposed to the top surface of the panel. The glossy side of the panel is usually placed under and the perforated surface is usually placed above when used as ceiling/floor of the buildings. This performs a mechanical interlock for the interconnection and coupling between the composite plates and the mortar of the floor covering tiles. The glossy side of the panels is waterproof and can also be painted as an exposed facade.

Sandwich panels, which are made from different layers of foam and metal plates, may be considered as similar new materials. However, these sandwich panels have a laminated structure which consists of layers stuck to each other. Therefore they may easily be detached from each other against strong tensions. But the mode of delamination and detachment in all the 3 directions of X, Y, and Z is canceled when the composite panels are reinforced by 3D woven fiberglass fabrics. Also, maximizing the distance of the mass from the center, bearing maximum bending moment, and increasing the maximum strength to weight ratio are possible. Thus the composite panels reinforced by the woven fiberglass fabrics have a high load bearing ability, high resistance against strong tensions and shocks in addition to the aforementioned qualities.

These building codes and regulations are under preparation. In the meantime, the building codes and regulations of LSF buildings could be used. The materials’ viscoelastic behavior, shear-ability, light transparency, joints and fittings as well as fire retardancy features are considered the most important characteristics that affect the preparation of the needed/required building codes and regulations.

Since these composite panels can be easily cut, drilled, resin welded and coated; therefore they are completely repairable.

These panels do not require any inspection or repair during their expected decades-long life span if they are coated. But if they are exposed to open space, it is recommended to be inspected once every few years, and be repaired if needed.

Depending on the case and the technical expectations from these panels, they may either be luted with filler cement and/or be jointed by H or T shape metal profile, and L shape for the angles. In the simplest way, the sealing and caulking processes may be quickly well accomplished by placing a piece of 2D woven fiberglass fabric, saturated with resin, over the neighboring edges of either or both sides of the adjacent panels.

Yes. Experiments have shown that these panels have the adequate bending stiffness for spans up to 120-centimeter wide. However, for more support, C channels perpendicular across the beams can be used below the composite panels. Testing for the spans over 120-centimeter wide is also in our plan. However, different layers of these composite panels may be stacked on each other using glue or resin. In this way, the bending stiffness of these panels will increase almost to the power of the panels’ thickness; therefore, these panels can be used over bigger beam spans.

Use of the T-shape metal profiles, whose edges are folded with glue or resin, will highly enhance the panels’ specs across the seam lines between the two adjacent panels. As the simplest alternative way, the strength enhancement across the seam lines of the two adjacent panels can quickly be accomplished by placing a piece of 2D woven fiberglass fabric saturated with resin on the neighboring edges on both sides of the adjacent panels.

While bearing a full load, these panels were tested at -25 to +210 Celsius, and showed no changes in their mechanical behavior. These panels’ behavior at these borderline temperatures was compared with the panels at normal temperature, and no meaningful difference was observed. No other tests beyond the borderline temperatures have been carried out yet. It is worth knowing that more fire experiments, beyond these borderline temperatures, have been performed, but have not yet been posted in our site.

The tests at 1.1 KHz frequency showed that these panels attenuate the sound for up to 21db.