Ventilation in the house of aerated concrete: device, requirements and norms

In the article we will look at how to make ventilation in the house from aerated concrete with our own hands. Aerated concrete is a fairly high-quality building material, which has a lot of advantages. Most importantly, it has a low cost and the houses built from it are very warm. But there is a drawback - aerated concrete also absorbs moisture well, and heat-saving qualities are greatly deteriorated.

In order to get rid of all the shortcomings, you need to ensure high-quality air circulation in the rooms. It is not difficult to do it yourself, but you will have to study all the recommendations and nuances. Otherwise, the system will not work properly.

What is a ventilation system for?

Before metal-plastic windows, stretch ceilings and various vapor-proof materials for wall decoration began to be introduced, there was practically no need for forced ventilation. As a rule, fresh air entered through leaks and cracks in the frames of wood, and excess moisture, absorbed by the walls of brick (or wood), gradually came out.

Thanks to modern materials, our life is made more comfortable and easier, but new troubles appear. There is a need to create ventilation in a private house from aerated concrete. Most homeowners do not forget to protect the walls from the outside from the effects of rainfall.

But the peculiarity of aerated concrete is that it easily absorbs excess moisture from all rooms. In this case, deformation of the finish, the appearance of mold and fungi, and most importantly, an unfavorable microclimate will reign in the house. But if you do not let the air stagnate, then you can avoid such consequences. And for this you need to make a quality ventilation system.

Varieties of ventilation systems

It is worth paying attention to the fact that the ventilation device in the house of aerated concrete has distinctive features. If in houses from traditional building materials channels are laid, as a rule, only in those rooms in which there is high humidity, then in this case it is recommended to do them in all rooms without exception.

If it is difficult to realize ventilation in all rooms, it is necessary to make it in the bathroom, kitchen, basement (if any), boiler room. At the same time, in all living rooms it is necessary to install special ventilation grilles on the interior doors or leave a gap under them so that the air can circulate freely. In private homes, the following types of ventilation are used:

• Natural.
• Mixed.
• Forced.

Examples of ventilation schemes

The ventilation system in the house of aerated concrete can be built according to one of the following schemes:

1. Passive ventilation. Air exchange occurs naturally through channels through the roof.

2. Mixed - exhaust fans are installed in those rooms where air pollution is greatest. The fans are switched on manually or automatically after a set period of time.

3. Exhaust forced ventilation - fans are placed in a common channel, which combines all the ducts coming from the rooms.

4. Forced-air and exhaust forced type - fresh air enters and leaves the exhaust using a mechanical ventilation system with a recuperator.

Now let's look at each system in more detail.

Natural air ventilation

Sometimes it is called passive - no means for artificial air movement are provided. How to make ventilation in the house from aerated concrete of a natural type? To do this, you need to know certain features, otherwise the whole system will not be able to function correctly.

Specifically, you need to do the following:

• Arrange all channels through which humid exhaust air will be drawn from the rooms. In order for it to stretch itself, you need to bring the channels over the roof of the house to a certain height. If the pipe is located one and a half meters from the ridge, then you need to raise it above it by about 0.5 m. If the distance is less than 3 meters, then the upper part of the pipe is allowed to be placed at the same level with the ridge. In the same case, if the distance is more than 3 meters, it is necessary to draw a line from the ridge at an angle of 10 degrees to the horizon. And the top of the pipe must be placed below this line. If these conditions are not met, traction will be bad.

• It is also necessary to make air flow from the street. Please note that plastic windows do not allow air into the room, but there is a way out. You can install special window units with valves for the inflow. Installation of built-in ventilators in the outer walls is also allowed.

Forced ventilation

Such a design is more difficult to install, and more expensive, and its operation involves the use of electricity, as well as various devices. But the cost of all equipment quickly pays off due to the fact that the microclimate in the house becomes much better.

Let's highlight several features of the system:

1. Exhaust fans are installed on the air ducts, air from the outside enters through a network of channels.
2. In order not to violate the temperature regime in the cold season, it is necessary to install devices for heating the air in the ventilation system.
3. The cheapest way to heat is not an electric heater, but a recuperator. This is a kind of heat exchanger, which has two fans - exhaust and supply. The heating of the air entering the house is carried out by gas, which is diverted to the street.

Please note that when installing a system with a recuperator, heat loss is reduced by approximately 30%. Typically, the device is placed in the attic and connected to a common channel. It combines air ducts that go from all rooms. It is necessary to provide free access to the recuperator - in it you will sometimes have to clean the plates and change the filter elements.

Mixed ventilation

In this design, fresh air enters the house in a natural way, but the exhaust is carried out using fans. Can be used:

• Fans built into the exterior walls of the house or windows of each room.
• One high power fan installed in the attic. Several ventilation ducts are connected to it at once.

Ventilation duct design

If you will make ventilation in a one-story house from aerated concrete, you need to consider that this building material is very fragile, unstable to high temperatures, and absorbs moisture well.

It is necessary to take into account the fact that air ducts must not be laid in external walls, as the risk of condensation increases.

You can make channels in the following ways:

1. Laying out of brick.
2. Sleeving with plastic or asbestos pipes.
3. Installation of galvanized duct and lining with small blocks of aerated concrete.

The latter method is considered the most expensive and time-consuming, while condensation appears on the walls of metal elements. And it is fatal for aerated concrete. For this reason, insulating material is required.

Brick channels

If you have not yet decided whether ventilation is needed in the house from aerated concrete, check out the consequences that await you if you do not.

When laying brick ventilation ducts, you need to know such nuances:

1. The fewer channels there are in a house, the better. It is recommended to make them in the walls of adjacent rooms in which a high degree of humidity. Usually it is a bathroom, boiler room, shower.
2. Be sure to use corpulent brick grades when laying. If you decide to use hollow, then all the holes in it should be filled with concrete mortar. Do not use silicate grades of brick - they do not withstand the temperature regime and crumble.
3. The solution must be applied carefully, do not let the mixture fall into the channel. All seams must be completely filled, grouting should be done in 2-3 rows. In this case, air will not penetrate into adjacent rooms and channels.
4. The walls of the channels need to be smooth inside so that no protrusions interfere with air circulation. To achieve this, you need to remove the excess solution from the inside and spread it with a trowel. It is also allowed to carry out the casing of metal ducts.

Can I use plastic pipes?

Metal pipes are expensive and it is sometimes more difficult to get them, but there are a lot of plastic pipes on sale. The advantage of plastic is also that condensation does not appear on it. Typically, round pipes with a diameter of 130 mm are used during installation. Sometimes use rectangular with a cross-sectional area of ​​150 square meters. cm.

Arrangement of ventilation in the house of aerated concrete is performed at the time when the walls are laid out:

• In the block, which is located at the level of the ventilation hole, you need to fix the outlet and connect it to the plastic pipe.
• To bypass the air ducts in the blocks, you need to cut holes that will be a couple of millimeters larger than the dimensions of the pipes. Please note that aerated concrete blocks are easily sawn with ordinary hacksaws on wood.
• Between the duct and the walls you need to fill the space with a solution.
• It is imperative to insulate the places in which the pipes pass through the roof and the attic.

In the attic, all air ducts must be combined into one channel and brought to the roof. You can also connect it to a fan or recuperator.

According to sanitary standards, the requirements are based on the exchange of air per hour, so for each room they will be different. To comply with them, you need to install pipes with the necessary section of the channel. For example, a pipe diameter of 150 mm will be enough for a living room, kitchen or bathroom. Choosing a fan is even easier, since the packaging indicates the performance of each of them.