- What is facade ventilation for?
- Ventilated facade – principle of operation
- Frame for ventilated facades
- Metal carcass
- Wooden frame
- External panels of a ventilated facade
The article describes the principle of operation of a ventilated facade, as well as methods of its construction. You will learn how to choose a ventilated façade system for your building. The article provides comparative characteristics of the frame, as well as prices for finishing panels.
Facade finishing performs not only decorative finishing, but also protective functions, protecting the load-bearing walls from the effects of destructive factors – wind, rain, sun. Therefore, special attention is traditionally paid to the correct arrangement of the facade..
What is facade ventilation for?
When finishing or reconstructing a facade, as a rule, its insulation is done along the way. In pursuit of the best thermal insulation, the customer often forgets or ignores the most important indicator of insulation – vapor permeability. This is fraught with big problems: getting wet, freezing and premature destruction of the bearing wall..
The principle of condensation formation explains how this happens: moisture accumulates on solid surfaces at the point of contact of different temperatures (cold and heat). This is often the cause of “ice walls” or deteriorated interior decoration. The only way out is to ensure that moisture can freely evaporate into the atmosphere, i.e. outside the building..
In this regard, when constructing facades “wet” (by applying mortar finishing layers), vapor-permeable compositions are used. In another case, a ventilated facade system is used.
Ventilated facade – principle of operation
Unlike a “wet” one, a ventilated facade does not have mortar layers, but it also reliably protects the wall, allowing moisture to escape from the insulation. At the same time, the method of mounting basalt or glass wool slabs is identical – on special glue and “umbrella” dowels (sometimes without glue). When installing a ventilated facade, anchors or an extension profile are pre-installed on the wall for subsequent fastening of the finishing material.
The fastening system provides not only a margin of space for the thickness of the insulation, but also air – the distance between the insulation and the protective layer (finish).
Ventilated facade: 1 – base; 2 – wall; 3 – anchor bolt; 4 – air flow; 5 – bracket; 6 – main guide; 7 – composite cassettes; 8 – thermal insulation
Important! The size of the ventilation of the ventilated facade with a wall height of up to 4 m is equal to at least 50-60% of the insulation thickness. At a higher height, the walls are divided into equal sections and additional intermediate air vents are arranged. At a lower height, less airflow is allowed, but not less than 30% of the thickness of the insulation.
The work of such a facade occurs mainly during the heating season, when the temperature difference is most pronounced. It happens like this: the wall is heated by heating from the inside and heats up some of the mineral wool. Accordingly, the moisture accumulated at the dew point heats up. At the moment of even a short-term increase in the outside temperature, moisture evaporates from the cotton wool, it dries out and the cycle repeats.
The efficiency of a ventilated facade is determined by the rate of evaporation of moisture, and this indicator directly depends on the volume of air passing through the duct.
Important! The better the air exchange in the air duct, the more efficient the ventilated facade.
Therefore, it is better to make the width of the duct with a small (10-15 mm) margin and carefully check for the absence of interference.
In the upper part of the facade, a ventilated space must be arranged. This is best understood by the example of perforated siding spotlights. The space above the soffit panels communicates with the wall ventilation. Relatively warm humid air rises along the wall, enters the soffit cavity and is eroded through its perforations.
Frame for ventilated facades
The main element of the ventilated facade is the frame. It can be of two types.
Consists of a set of profile and stamped parts made of galvanized steel with a thickness of 1.5-2 mm (horizontal elements) and 0.5-1.0 mm (vertical elements). They are used for cladding high-rise buildings with materials weighing up to 70 kg per 1 m2*.
* All indicators of bearing capacity are indicated per cell of the grid of attachment points no more than 600×600 mm.
In general, the metal frame is a balanced system, every detail of which is checked and tested before production. Handicraft production of such systems is not practiced due to high production costs. Therefore, the confidence in any such system on the market is quite high..
- High reliability and trust (requires certification).
- Manufacturability, ease of use (all parts fit well).
- High load-bearing capacity (up to 70 kg / m2), finishing material is unlimited.
- Resistant to atmosphere (galvanized metal is insensitive to moisture).
- System mobility (compensates for thermal expansion of the metal).
- High cost of the system (compared to wood).
- Supplier binding (you must order a kit from the manufacturer or seller).
- Indispensability of parts (elements of different systems are not interchangeable).
- Requires a variety of tools (riveter, grinder, etc.).
The analysis of the properties of the system leads to the conclusion that it is well thought out, reliable, but at the same time it is expensive. An alternative to metal, in this case, can be wood.
This system is created on site from a bar of 50-60×50-60 mm. It is mounted in a primitive way – by simple through fastening to the wall of the guide itself. In this case, the timber, between which the insulation plates are installed, is located horizontally. Then a vapor-permeable waterproofing – a superdiffusion membrane is rolled onto it and pressed with a vertical counter-lattice. At the same time, the maximum thickness of the insulation is 50 mm with an air flow of 20-25 mm (counter-lattice rail 20×40).
- The cost of the system is several times lower than the metal.
- Two units of power tools are enough – a hammer drill and a screwdriver.
- Material availability.
- All wood problems (drying out, insects, etc.).
- Lower bearing capacity (up to 20 kg / m2).
- Less leveling accuracy (due to the lack of lumber).
- Limited use of finishes.
It would be logical to use a wooden frame on light frame walls for light finishing, provided that the wall is insulated inside. The option is good if you have a tight budget.
Combined framecombines the best properties of both systems. The principle of the device: an ordinary galvanized corner is mounted to the wall, on which horizontal guides are attached. To them, in turn, a vertical counter-lattice is attached. The properties of such a framework:
- The cost of the system is more expensive than a wooden one only for the price of corners.
- You can install up to 250 mm of insulation (for the length of the corner shelf).
- Bearing capacity – up to 40 kg / m2.
- Convenient to attach finishing material.
- Any finish can be applied, except for heavy types (metal, stone, porcelain stoneware).
All three options are good in their own way, and further we will tell you what appearance possibilities a ventilated facade provides.
External panels of a ventilated facade
There are several types of finishing elements. They are subdivided according to their weight and belonging to the system..
Artificial stone slabs * (porcelain stoneware).They have regular shapes and are designed for cladding urban buildings. The stone is extremely reliable and durable – none of the installed systems has yet reached the real service life. Can be purchased separately from the system, which provides for fastening for stones of different thickness.
Cassette panels *.Factory products interconnected with the type of frame guides and the type of fastening. Usually they are calculated, produced and installed by one firm..
Linear panel *.High-tech polyester product. Has protective and insulation properties.
* Porcelain stoneware, cassette and linear panels are mounted only on the factory metal frame.
Block house– wood material, average in price and weight. For its installation, a wooden crate is required, so the frame is best to choose a combined.
Lining.In fact, this is a lightweight block house, which means that an ordinary wooden frame will be enough..
Vinyl siding.The lightest and easiest exterior decoration material to install. It is convenient to mount it to the rail with screws or nails. Siding weight – 2-4 kg / m2, therefore a wooden frame is suitable. Moreover, the siding system is self-leveling.
Finishing panels.This is a huge number of various panels of polymer origin. They are made of polystyrene and polyurethane foam, they are called thermosiding and basement panels, and are also mounted directly to the wall. Any panel over 600 mm in length can become part of a ventilated façade. Depending on the weight, a wooden or combined facade is selected for it.
Table. Prices for finishing panels for a ventilated facade
Position Material Thickness, mm Cost 1 m2, at. e. Cassette panel Steel, PPE 20 15 Cassette panel Aluminum, PPE 20 22 Cassette panel Composite, PPE 20 8-12 Linear panel Polyester 0.15 7 Block house Pine 22-35 8-15 Plates suit. stone Porcelain stoneware 6-12 12-25 Lining Pine 12-14 4.5 Siding Pvc 0.1 8-15
By choosing a ventilated façade, you will not only give your home a unique look, but also provide the best protection against the elements. This will extend the life of your home for decades..