The arrangement of the roof ends with the laying of the roofing and the installation of the ridge. This is a crucial stage, since a whole range of technical and protective qualities of the house depends on it. The most beneficial will be the creation of a ventilated ridge, which will provide ventilation of the under-roof space, exclude the penetration and accumulation of moisture in it.
The benefits of ridge air exchange
The tasks of ventilation in the roof area can be solved in various ways. A huge range of designs that allow you to organize a vertical duct through the channels from rooms to the roof, makes it possible to provide effective ventilation for any type of roof. For common metal and profile coatings, a seamed ventilated ridge is often used, which has a number of operational advantages:
- Tightness. The closed design virtually eliminates the possibility of penetration of dirt and insects into the under-roof niche.
- Reliability. The same pitched flanged roofs with a vent ridge support the basic functions of a roof covering, providing protection against precipitation, wind and physical influences.
- Effective ventilation. The main task of this element, which is solved by a special gap. It is performed in such a way that at the same time a barrier to external influences is provided and at the same time the circulation of air flows is maintained.
- Mechanical resistance. The skate can be constructed from different materials, but usually a high-strength elemental base on a metal-plastic basis is used.
- Vent-skate can be used both on classic gable roofs, and as part of more complex structures such as hip.
Skate device with the possibility of air exchange
The skate itself is a rafter node located at the top of the roof. It is formed as a result of the reduction of two slopes at least, the bearing beams and the elements of the crate are mated. The top layer of the roofing does not fit. A feature of the ventilated ridge device is the preservation of the gap between the pitched surfaces. Along the entire line of the ridge, gaps are formed continuously or alternately, through which air flows out. But the following question arises: how is reliability and tightness maintained with such a design? These and other protective qualities are guaranteed by a patch plate of a triangular shape, which closes the seam strictly at the upper point and on the sides. It would seem that a zigzag path is formed along which air can exit only with great difficulty. Nevertheless, this system works quite efficiently.
The principle of operation of the structure
In order for air flows to pass stably through the ventilation duct system (rising and lowering), a thrust of the corresponding force is required. To create it, two conditions must be observed:
- Natural convention. The law of physics, which will apply to any under-roof spaces where, in principle, warm humidified air is located. Heated streams rush out, being replaced by cold air. This creates the basic condition for the ventilated ridge to function as an effective air exchange and ventilation system.
- Sufficient air flow. In the attic, which is completely sealed at the lower and middle levels, there is no physical possibility to replace the warm air; accordingly, the circulation will not work. Correct the situation using spotlights with perforation in the eaves system. They will become sources of cold air coming from the side of the lower overhangs. Further, the air is heated, moistened and sent upward, passing through the holes of the ridge.
Technical Options
There are two approaches to doing vent skate. The first involves the use of an aerator. This is a plastic overlay with factory perforation, which is mounted on a convergence unit of two slopes, fixed with hardware and covered with roofing material. The average length of the aerator is 1.5-2 m, so several segments may be required per roof. They are interconnected by built-in locks on the principle of a hook.
The second method involves the independent installation of a ventilated ridge without the use of an aerator. The design, on the one hand, is simplified, and on the other hand, it requires increased attention to details from the performer, since the ridge is also an essential element of the roof frame. At the point of convergence of the slopes in this case, a triangular lathing-pad of bars is arranged. Between its elements leave gaps, which are also covered with a layer of roof.
Aerator Installation
The central part of the roof aerator should be installed strictly on the ridge beam so that both sides of the slopes are captured. You should not be afraid of a tight lining on the roof along the outgoing sides, since the ventilation channels in the aerator are built-in and do not involve leaving additional holes. Difficulty can arise only with the installation of a ventilated ridge for a folded roof, which has a corrugated coating. Accordingly, unwanted eyes will be left, which in the future will have to be separately sealed with waterproof adhesive.
DIY vent skate making
This method is applied to pitched units with an interval of about 30-50 mm. This will be the ventilation gap for the roof duct. The master’s task is to raise the ridge lining by about the same 50 mm to provide a side channel for the circulation of flows, which in practice will direct air down the slopes, and will not allow dirt and precipitation to pass into the under-roof niche. A ventilated ridge is mounted on a roof of this type using bars of the standard crate type. A bearing wooden base is mounted along the entire length of the ridge , on which a metal protective casing is laid, and then a roof.
What else to consider when ventilating a skate?
Among the additional devices, power, filtration and decorative elements can be provided. Reinforcement is created by including rear mounting rails and metal profiles, which on the side of the truss structure are stiffeners. Filtration is carried out in aerators in a natural way, and with self-installation it can be realized with membrane vapor-permeable linings and seals in the crate. As for the decoration, the ventilated ridge is usually decorated with non-standard roofing plates of the original form. These can be inserts with panels in the color of profiles or masonry, but with a prominent texture.
Conclusion
The choice of ventilation skate installation technique depends on the characteristics of the roof and its components. For example, for coatings from a metal sheet of a flange type, it is quite possible to apply the technology of the device of the crate. If you plan to install a ventilated ridge for a soft roof, then it is better to turn to ready-made solutions with aerators. Such devices protect the under-roof space well from moisture and dirt, and also effectively support the bearing function in the rafter system. And in both cases, it is important not to forget about sealing joints that are not related to ventilation as such.