When designing and constructing buildings for various purposes, plastic windows open up completely new architectural possibilities. The window system is formed by both main and additional profiles.
The base of the entire window system is formed by the main profiles, which include: profiles of sashes, boxes, crossbars, imposts. Special profiles for pivotless hinged windows also belong to the main profiles. These also include shtulp profiles. Manufacturers quite often release the main profiles of several names. The main profiles, depending on the design loads and the architectural composition, are installed in various combinations in the window.
The most common three-chamber profiles, which have a main chamber, a drainage chamber and a chamber where fittings are attached. However, three-chamber profiles are not always used. All well-known manufacturers can offer a variety of profile models, which differ in the number of cameras. This gives the designer the opportunity to adapt more flexibly to specific tasks to be solved..
You can, for example, remove one chamber in favor of powerful reinforcement, or, conversely, add one chamber to the profile to increase its thermal resistance.
The sash and frame can have outer surfaces that will be offset relative to each other or will be located in the same plane. If the sash and frame are flush, then pre-chambers (additional chambers) appear in the profile. This allows the glazing to be installed with a greater thickness. This design is called one-plane.
Let’s look at the example of a combination of a sash and a box, the purpose of each camera.
The main chamber is required to install the reinforcing profile (reinforcement liner).
The thickness of the walls and the section of the reinforcing profile are taken on the action of wind loads based on the static calculation of the profile. The possibility of thermal deformations is also taken into account. Reinforcement liners are made, as a rule, of galvanized steel, and sometimes of aluminum. They protect profiles from strong deflections that can occur due to the low value of the modulus of elasticity of PVC. PVC windows, due to the presence of a reinforcing insert, received another name – metal-plastic windows.
To drain water that penetrates through the seal during strong wind and rain, a profile drainage chamber is used.
To do this, a rebate is made in the sash and frame, which has a slope or a special recess to the outer edge. Water flows into this recess, which then falls into special drainage holes, which are cut along the length of the box and the sash of the drainage chamber at several points.
Porous seals are installed along the entire contour of the sash and frame to ensure water and air tightness. This system has an outer and inner contour. The outer seal can be installed in the middle and along the outer contour of the window profile.
Seals are made of a material that is designated by the abbreviation EPTK, that is, ethylene-propylene-thermopolymer-rubber. This material has low resistance to fats and mineral oils, it is resistant to alkalis and acids and swells in hydrocarbons and gasoline. Moreover, swelling is a partially reversible process..
The box and sashes have grooves along the entire contour for fixing glazing beads.
The profile of the glazing bead is determined by the architectural concept and can be very different. There is a groove on the glazing bead, into which a seal is inserted, pressing tightly the glass or glass unit.
Shtapik is an additional profile. All additional profiles differ in variety in each window system, so they are very difficult to classify. However, the main groups of additional profiles can be distinguished, nevertheless,.
The first group includes profiles that are used to ensure technological and high-quality installation of the window unit. These profiles include extensions, strips, cladding profiles.
The second group includes profiles that define the variety and flexibility of architectural solutions. These include connectors, glazing beads, pivoting profiles and decorative covers..
Well, the third group includes reinforcing and restoration profiles.