- Functions of the facade frame
- Types of subsystems for ventilated facades
- Frame configuration for curtain wall
- Start of installation: we prepare the wall and fix the consoles
- Assembly of the fixing profile system
Finishing using ventilated facade systems begins with the installation of the frame subsystem. Errors at this stage are fraught with incorrect performance by the facing of its functions and even complete destruction of the finish. Let’s talk about frames for independent ventilation facades and the features of their installation and assembly.
Functions of the facade frame
The hinged ventilated facade conceptually derives from the external glazing systems of high-rise buildings, from where it inherits its technological complexity. The high versatility of such a finish is achieved due to a very specific fastening subsystem, which performs a number of target functions.
Of these, the main one is the distance of the cladding panels from the load-bearing wall and the insulation layer to obtain a space in which street air circulates freely. This is one of the most effective ways to protect high hygroscopic insulation materials. For half a century of active implementation, this method has proven itself only from the best side. Due to the external cladding, the temperature exchange of the structure is normalized: in summer the sun heats the walls less, and in winter the air gap prevents the diffusion outflow of heat.
1 – protection of the building from heating; 2 – protection of insulation and structures from precipitation; 3 – ventilated facade subsystem; 4 – vapor-permeable membrane; 5 – insulation; 6 – removing moisture from the room
On first acquaintance, the system demonstrates obvious complexity and creates the illusion of unreliability. From here comes the second key function of the frame – to protect the insulation and the supporting structure without compromising the integrity of the cladding and its appearance. This becomes possible due to the high resistance of individual frame elements to mechanical stress and competent load distribution.
It can be concluded that such a high manufacturability is very expensive, both from the standpoint of economic availability and from the point of view of the complexity of installation. Therefore, the third task that is posed for the frames of independent ventilation facades is a high degree of component unification. This not only makes possible the fastest possible execution of work with a high degree of participation of expensive industrial mountaineering. The framework for ventilated facades can be adapted even for very complex architecture, including surfaces with deviations from the vertical.
Types of subsystems for ventilated facades
Today there is a very wide range of frame systems for ventilated facades, each of which is designed to work in the specific conditions of the facility with a specific type of finishing material. To classify them, you should pay attention to two key features.
The first is the material for making the frame:
- Galvanized steel. Optimal for façade systems without claims for durability in favor of cost savings. Most often used in the construction of inexpensive aluminum and polyurethane facade cladding with the prospect of their replacement.
- Stainless steel. Frames made of it are the most durable and are used for cladding high-rise buildings using heavy panels (once and for a long time).
- Aluminum substructure. It is used in restoration and insulation projects for old buildings, where the permissible load on load-bearing walls cannot be exceeded. Disadvantage – low fire safety, aluminum subsystems are not used in high-rise construction.
- Water-repellent wood. Used as rack elements in low-rise buildings and regions with mild climates.
The second distinguishing feature is the manufacturer of the frame system. Elements of different brands are not comparable with each other (with very rare exceptions), therefore they are always supplied in a complete set. The choice in favor of a particular manufacturer is determined mainly by the convenience and manufacturability of installation. This is almost unimportant for a private developer, but with the involvement of industrial climbers at large-scale facilities, the need to drill or cut something extra translates into dozens of extra man-hours.
Frame configuration for curtain wall
The third key difference is the form factor of the finished frame system. It depends entirely on the format of the used cladding and every self-respecting manufacturer considers it his duty to support all three types in his assortment. In addition, if they are warranted by the cladding manufacturer, they should only be installed on the recommended subsystem. By form factor, frame systems are divided into:
- vertical orientation: for siding horizontal layouts and continuous preparatory sheathing with slab materials;
- horizontal orientation: for vertical siding, magnesite and polyurethane panels;
- cross type: for marble, brick, porcelain stoneware and other heavy panels.
Before proceeding with the installation, a technological map and an album of technical solutions for a specific product are studied. The goal is to establish the order of assembly and the operation of the connectors. Fortunately, almost all manufacturers have the same comparison scheme and package contents. They have stationary brackets that are directly attached to the wall, and a movable profile, which together with the first element forms the base console. The movable bar has a standard method of connection with the rack elements of the frame, plus the kit may include connectors for building up racks, corner and cross connectors.
Start of installation: we prepare the wall and fix the consoles
Installation begins with the preparation of the walls: removal of the remnants of the destroyed finish and antiseptic treatment if there are signs of mold damage. Installation of consoles begins from the top row, installing them with a step, normalized by the type and weight of the cladding. Installation is carried out on a plastic lining, which excludes heat migration between the wall and the frame, the fastening is carried out with anchor bolts, and in the case of loose and hollow bases – chemical anchors or special types of dowels (CAT, KBT). Then a plumb line is thrown from each bracket along the wall, along which holes are drilled and the remaining elements of the vertical row are installed.
Many manufacturers distribute the mounting holes in the consoles so that they can be assembled, which greatly speeds up the work. After fixing, the movable strips of the consoles of the upper row are lined up in a common line according to the curvature of the wall plane. Then the plumb line is outweighed to the edge of the upper console and so the remaining sliding parts are adjusted and fixed. Both bolted joints and blind rivets can be used to secure the sliding bar..
If the subsystem is assembled with the horizontal orientation of the rack elements, the method of adjusting the consoles remains the same, but the brackets are rotated in the other direction. Thus, first, the extreme vertical rows are installed, along the elements of which the fishing line is then stretched to align the intermediate brackets of the horizontal row.
Assembly of the fixing profile system
Sometimes it is recommended to fix the consoles after fixing the racks of the frame system. If this is the manufacturer’s recommendation, it is perfectly acceptable. However, plumb-line alignment is considered the preferred method in the absence of additional installation requirements..
The profile usually has standard means of preliminary fastening, represented by grooves and latches. After fixing in place of installation, the rack elements are fixed along the inner shelf to the sliding console bar using bolts, rivets or unhardened self-tapping screws.
Most “proprietary” systems involve the installation of fastening profiles after the installation of insulation and windproof membrane / film. However, it is possible to lay insulation mats not only under the crate, but also between the posts. In this case, a windproof film is rolled out over the profiles and a system of distance rails with a vertical or two-layer cross orientation is assembled.
At the end of our review, we note that the basement and front part of the wall are separated by a horizontal ebb plank. This addition is designed to limit the flow of moisture-saturated air from the foundation into the main duct space and prevent water – condensation and oblique rain – from entering the basement. Thus, air convection in the two zones occurs separately..