What is the plastic?
Plastic - Description
It is a plastic specially designed for the construction of canopies for terraces, shelters, garages, partitions, greenhouses, etc. Its high strength combined with lightness makes it so popular. The structure of the polycarbonate sheet resembles a honeycomb. Inside, there are hollow chambers, which cause stiffening and improve the insulation properties (air is a good insulator).
It is available in a clear version, which transmits light best, and in opal and smoky brown colours, among others. The latter varieties can be used where there is high insolation (eastern and western parts of the building).
A plastic material with excellent insulation parameters and resistance to mechanical damage.
10 x lighter than glass
Clear, graphite, brown.
Boards available in formats up to 2.1 m x 13 m.
Roofs, glazing, greenhouses, conservatories, skylights, partitions and much more.
What are the parameters of cellular polycarbonate?
The material is made from polycarbonate resins. The material has very good mechanical and physical properties. Boards made of cellular polycarbonate, also called hollow-core polycarbonate, are relatively light, with a density of 1.2 g/cm³. Other important characteristics include tensile strength (﹥70 MPa), good light transmission coefficient (1.58), insensitivity to extreme temperatures (the operating range is -40 to 120ºC) and water absorption (23ºC - 0.36%).
Cellular polycarbonate is therefore a proven, resistant material. Thanks to its properties it is slowly replacing ordinary glass, still commonly used in the construction industry. Unlike glass, cellular polycarbonate is not so easily damaged mechanically - it can even withstand stone hits. For this reason it is very often used in buildings exposed to acts of vandalism or accidental damage (e.g. in production halls and warehouses). In addition, the panels made of this material are easy to keep clean. Lack of a rough surface means that dirt does not stick to their surface, and maintenance requires only a water-soaked cloth.
Processing of cellular polycarbonate
This type of polycarbonate can be cut, sawn or drilled with the use of special tools such as circular, hand or band saws. It is important that after cutting the plate from cellular polycarbonate, it should be carefully protected against the ingress of dirt - dust or other contaminants may impair its transparency, making it look bad. To protect the cut edges, vapour-permeable tape should be used at the lower edge and full tape at the upper edge.
In order to fix the boards to the roof or other structure it will be necessary to drill holes in the board. The rule is that these holes should be slightly larger than the connecting element - this protects the board against cracking or damage as a result of too much pressure from screws etc. So initially we drill a smaller hole and enlarge it if necessary during work. Drill with a typical twist drill bit for metal.
Assembly of cellular polycarbonate structures
Twin-Wall Sheets can be used as a roofing material, but it is recommended that the roofs are flat or inclined by a minimum of 5 degrees. Inadequate bending may cause high intensity and consequently damage to the board or cracking of the top layer, which is intended to protect against uv radiation.
The boards are fixed in the profiles. When using this type of fixing, the panel must be securely placed in the profile and protected against slipping. It is also important that the slab is firmly fixed, as snow loads or precipitation can cause damage to unstable roof structures.
The panels in the profile must be fixed in such a way as to allow for the expansion of the panel due to the thermal expansion that the cellular polycarbonate has.
It is also not advisable to fix panels with open sides, as moisture, dirt and dust easily penetrate these areas, affecting the quality, safety and aesthetics of the roof.
We have already discussed the choice of tiles. Now it is time for another important subject - securing the edges of the boards. In order to prevent anything from getting inside the chambers, we have to properly secure them.
Security tapes are used for this purpose. There are two types of such tapes: vapour-barrier (otherwise known as full) and vapour-permeable. The former (white in colour) should be applied to the board edge located higher, i.e. where the slope of our roof begins. This is where it is potentially easiest for water to get in.
The second, vapour-permeable one is needed at the bottom. In case any condensation occurs it will be possible to evaporate through it. Tapes are available in several widths, which we select according to the thickness of the polycarbonate sheet. Tapes with a width of 25 mm are suitable for slabs of 4, 6 and 8 mm. A 35 mm wide tape will be useful for 10 and 16 mm thick sheets. The widest 50 mm will suit the thickest 20 and 25 mm sheets.
Once the appropriate tape has been applied at both ends, the F-type cap profile can be attached. This profile is necessary at least at the upper edge of the canopy. It should be fixed to the wall or structure and then the boards secured with proper tape should be inserted into the gap (remembering to peel off a few cm of protective film).
In the lower part we can use the same type of profile or a closing profile made of polycarbonate, type U. The F-type profile can also be used to finish the sides of the roof. However, the side chambers are not uncovered so it only plays an aesthetic role. Both types of profiles come in different thicknesses corresponding to the thickness of the polycarbonate sheets. The lengths are also different. The F type profile has a maximum length of 6 metres. It can be cut to the required size. In this way it can run even through the entire length of the canopy in one section (if it is not longer than 6m). The U-profile is sold by the piece in 2.1 m sections (this is the width of the polycarbonate sheet). Each panel on our roof will be finished with a separate profile.
Joining polycarbonate sheets
As mentioned earlier, the boards are produced in dimensions 210 by 600 cm and 210 by 700 cm. These dimensions are inconvenient and expensive to transport. We rarely need such sizes. Fortunately, we can join the boards with special aluminium profiles. The 60×9 aluminium top profile with the S229 seal is used for this.
The picture shows two panels and a top profile with a rubber seal. When screwed from the top, the whole thing will form a tight connection protecting against water penetration. It is important to remember to leave a space between the boards. Polycarbonate is a material that "works" strongly under the influence of temperature changes. If you do not leave the space empty, it may cause characteristic crackling. At the bottom, under the panels, you can see the S228 bottom gasket. It can be optionally fixed to rafters or to the profile. Its task is to additionally seal and dampen the noise of the "working" polycarbonate. When ordering connection profiles, remember to order a S229 gasket that is twice as long as the profile. This is, of course, due to the fact that we press the gasket on both sides of the upper profile.