What is roofing ventilation, is it necessary?

In those cases when you insulate the attic (attic), as well as install waterproofing under the roof, you definitely need roof ventilation, as this device will provide a greater operational resource for roofing materials. Unfortunately, many people neglect such a security measure, and for good reason!

Flowing air circulation under the roof provides not only the absence of condensation on the roofing material, but also serves as a thermal layer that prevents the penetration of cold or heat during cooling or heating of the finishing material.

Ventilated system for pitched roofs

What does it give

• In any case, under the roofing material will be collected water vapor, penetrating upstairs from the attic or attic. As well as condensate arising from the interaction of the internal heat of the room and cooling the coating material. If the roof ventilation is arranged - the air will circulate, then this natural air flow will simply drain the moisture, therefore, the coating will not be so destroyed.

• Circulation of air under the roof will equalize its temperature, especially with regard to metal tiles and corrugated flooring - this way you can avoid ice freezing in different places.. Such glaciers can be formed on canopies, which, without ventilation, will turn out to be the coldest in the whole area, and the melting snow will complete its work. In addition, safety instructions will be observed in this way - chunks of ice will not slide down from the shed because they simply will not be there.

• On hot sunny days, the roof surface is heated to such an extent that it is impossible to touch it, as it threatens to burn the body, but the moving air will cut off the heat from the attic or attic. In addition, due to the circulating flow, surface heating will not occur as much.

Note. In fact, roofing ventilation is nothing more than an internal convection of air that moves from the bottom up, from shed to ridge.

The author of this article quite often had to deal with such a situation, when the owners are ready to pay big money for the best building materials, but not for ventilation, when building a house or repairing a roof.

In most cases, this is due to two of the most banal reasons:

1. first, people simply do not know what it is and why it is needed;
2. and, secondly, they are not satisfied with the additional price that builders charge for such a device.

Of course, this is difficult to give a logical explanation, but, nevertheless, a lot of people, due to incomprehensible mercantile calculations and unreasonable suspicions of being engaged, are ready to reduce the life of expensive material.

Now let's see what happens when there is no air movement under the roofing material. And if in the heat it just means a high temperature (much higher than outside) in the attic or attic, then in winter time everything is much worse.

According to the laws of physics, warm air always rises, therefore, streams from a warmer ceiling will rush to the roof, on which snow lies, and it will begin to melt from below and this layer is covered with an ice crust, but what happens?

Note! Roofing material overlaps, that is, the edge of one element overlaps the edge of another. But at this junction there is still a gap of a few microns, which is not terrible in normal rain, as it is slightly above the common plane and the water just flows down, not having time to penetrate the gap.

But if there is an ice crust on top, then there is a so-called back pressure, which pushes this water into all micron gaps. That is, the roof starts to leak. But this is not all - the coating material will decompose due to the constant presence of moisture, even if it is aluminum-galvanized.

Different ventilation systems

If you want to buy components on the market for arranging such a system, you may encounter different offers, and all of them will be good, and their choice will depend on your personal preferences. However, bottom airways or entrances are always closed with perforated plastic or metal strips for decoration.

Although this condition is purely design and has nothing to do with technology. But exhaust air can already be of different types - continuous and point (aerators).

In the case of aerators, they are installed in separate areas of the slope or in some places of the ridge, depending on the crate that covers the truss system. As a rule, such products are shaped like a mushroom, as you can see in the photo above.

In addition, each of the aerators can be equipped with an axial exhaust fan and even be in the same circuit with the general ventilation of the room.

But best of all, it’s a continuous do-it-yourself, self-assembly, set on a skate and provides the best possible circulation. Such devices are decorated with roofing material and it is even impossible to notice.

Conclusion

Of course, you understand how important roofing ventilation is, and the video in this article will help you understand the topic in a visual manner. The fact that the stinginess has to be paid in double size, many certainly know - so it’s better to learn from others, and not from your mistakes and blunders (see also the article Shiber for ventilation: device, purpose of use, alternatives).