In an atmosphere of freshness

In a modern country house, a comfortable microclimate must be maintained regardless of the vagaries of the weather. Caring about it falls on the shoulders of climate systems.

Photo by E.Luchina Architect G.Legzdinsh What does a person need for complete «climatic happiness» within the boundaries of a single cottage? Firstly, effective ventilation of all rooms, without which a modern country house with its sealed windows, walls and doors runs the risk of turning into a gas chamber in a matter of hours. Secondly, the optimal balance of temperature, humidity and air velocity in the rooms.

ATThe composition of climate systems that provide comfort can include a variety of devices. Today we will talk about the methods of ventilation of a country house and the equipment necessary for organizing air exchange in its premises throughout the year.

Fresh air

As a result of human activity, the oxygen content in indoor air decreases, and carbon dioxide becomes too much. Poor-quality building materials, furniture, household appliances emit harmful substances. Air purifiers are not able to return the air to its original purity. Therefore, the exhausted room air, saturated with fumes, dust and bacteria, must be regularly replaced with fresh air.

Photo by K.Manko Architect G.Dimavichen
In bedrooms where people smoke often, intensive ventilation is necessary. The norms of air exchange in the rooms of residential single-family houses are given by SNiP 31.02-2001. According to this document, the performance of the ventilation system at home in maintenance mode should be determined on the basis of at least a single air exchange for 1h in premises with permanent residence of people. It is required to remove at least 60m³/h, from the bathroom and toilet— 25m³/h The air exchange rate in all ventilated rooms in non-operating mode should be at least 0.2 of the room volume per 1h. An increase (of course, to reasonable limits) in the amount of supply air usually has a beneficial effect on a person’s well-being, a decrease leads to a decrease in efficiency, and sometimes to diseases.

The calculated values ​​of air exchange for the premises of a country house are given in the Code of Rules for the Design and Construction of Engineering Systems of Single-Apartment Residential Buildings (SP 31.106-2002).

Estimated values ​​of air exchange in the premises of a single-family country house (SP 31.106-2002)

There are plenty to choose from!

House on seven winds

During ventilation with natural induction, air enters the rooms through leaks in the windows, and is removed through ventilation ducts embedded in the walls. In the vast majority of country houses of permanent residence, a system with natural induction of air removal is used. It is suitable if the air outside the windows is slightly polluted, and it can be let into the premises without prior purification. The system works due to the difference in the specific gravity of cold outdoor air (heavier) and warm room air (lighter). Fresh supply air mixes with room air, constantly reducing the concentration of harmful substances in the atmosphere of living rooms, then the mixture moves through the undercuts of interior doors in the direction of bathrooms and kitchens, carrying with it excess carbon dioxide and pollution. Along the way, the flow heats up and becomes less dense, as a result of which it rises to the ceiling. The polluted air leaves the house through the wall ventilation grilles on the ventilation stacks in the bathrooms and kitchen, which create a slight vacuum in these rooms.

Compact forced-air installation of the CAU-mini (Shuft) series with electric air heater —
In order for the natural ventilation system to work, you must first organize the flow of fresh air into the rooms. You can limit yourself to regular manual ventilation. However, even if you open the window a little, you let in noise. Also, keeping windows open is often not safe. In winter, with burst ventilation, the heating system does not immediately cope with a decrease in air temperature, hypothermia and drafts are possible.

Sometimes, for supply ventilation of residential premises, holes are punched with a diameter of 22-30mm under the window sills, just above the radiators. The heated air, rising from the batteries, draws cold outside air through them. After ventilation, these holes are closed with stoppers to preserve heat.

Exhaust ventilation ducts are often combined into a block with a chimney. They are made of red brick, removed simultaneously with the laying of the wall according to the project, starting from certain marks. It is still better to organize a constant supply of fresh air with the help of specially designed supply devices built into the window structure. Models installed in the opening of the window block between the sash and the frame are produced by companies— profile manufacturers: KBETrocal, Salamander, Kmerling (all— Germany) andetc. Overhead devices mounted on the window frame are supplied to our market, for example, by the company Aereco (France)— about 1.4thousandrub. per set for one window. Effective use of ventilators built into a through hole in the wall of each room of the cottage,— wall supply valves. They are offered not only by foreign— Aereco and Siegenia-Aubi (Germany), Systemair and Fresh (both— Sweden), Onninen (Finland), but also domestic firms, for example «Engineering equipment«. Each wall valve will cost you 2.5-5thousandrub. plus installation costs— it’s still about 1.7-3.5thousandrub. Provision should be made for the removal of air from the kitchen, toilet, bathroom and, if necessary, from other areas of the house (garage, boiler room, etc.). Exhaust ventilation risers (ducts) are usually carried out in the walls next to chimneys (chimneys). The structure of both depends on the design of the house. Sometimes a «bundle» of smoke and ventilation ducts is laid out of brick or special blocks on a separate foundation. If they forgot about ventilation during the construction of the house, then you can always save the situation by making risers from an asbestos-cement pipe with a diameter of 150-200mm— from the ceiling of bathrooms and kitchens to the roof (preferably 40-50see above the skate). At the same time, the minimum height difference between the levels of air intake in the premises (place of installation of supply grilles) and exhaust (exhaust pipe head) must be at least 3m.

Photo by E.Luchina Architects R.Kotov A.Kyresaar
In summer, natural ventilation is inefficient — to ventilate the premises, you have to open the windows. The main disadvantage of the ventilation system with a natural impulse is that its efficiency depends on variable factors.— air temperature, wind direction and speed. Normally, such a system functions when the windows are below 5C. In winter, you even have to close the blinds on the exhaust grilles in the bathrooms and kitchen, otherwise unproductive heat loss is inevitable. BUTin summer, the natural ventilation system practically does not work, although during this period some rooms (kitchens, bathrooms, damp basements) must be intensively ventilated.

But traction in the summer is easy to increase. This is facilitated by heating the ventilation ducts. The closer they are located to the chimney of a year-round functioning boiler or geyser, the better the ventilation works. If the chimney is removed from the ventilation riser, a low-power water heater connected to a separate branch of the heating system can be installed in the root part of the latter, or DHW pipes can be laid nearby.

Lomanco
Deflector (a) and rotary ventilation turbine (b) Another way to increase thrust— create a vacuum in the ventilation risers. For this, special devices are placed on the roof, on the heads of the ventilation ducts.— deflectors. The air flow (wind) flows around the deflector, creating a vacuum in the diffuser of the device, thereby ensuring the suction of air from the risers. A wide range of deflectors is offered by Uniwersal (Poland), as well as «Moven«, «tayra«(Russia) andetc. Recently, spherical rotary ventilation turbines have been sold in Russia— Turbovent (Russia), Lomanco (USA), which are mounted on the heads of ventilation pipes of cottages. Despite the direction and strength of the wind, the turbines rotate, providing a weak vacuum in the ventilation risers and pulling polluted air out of the house. Systems are very popular in America. The common problem of deflectors and turbines— in calm they are useless.

If a house served by natural ventilation has a powerful fireplace with an open firebox, then during its operation, not only in summer, but also in winter, polluted air can go from bathrooms, kitchens and other rooms to the fireplace room, along with unpleasant odors and harmful substances. After all, the fireplace itself is a powerful exhaust device that can remove up to 500m³/h of air. To avoid such reversed draft, it is necessary to ensure an abundant supply of air from the street directly to the firebox.

Regardless of the weather

Relatively more reliable (because it does not depend on the weather and effectively prevents the circulation of draft) is a ventilation system with mechanical induction of air removal. tributary— natural outflow— forced.

Mechanical ventilation system. Fresh air enters the premises through window valves, polluted — removed from bathrooms and kitchens with one powerful exhaust fan and air ducts BIn such a system, fresh air enters the house through window or wall valves. Extraction from bathrooms and kitchens is usually carried out using one powerful exhaust fan (capacity— 300-6000m³/ h), mounted in a heated attic and connected to ventilated spaces through air ducts. Ventilation grills with adjustable shutters, or exhaust pipes with a turntable and a cover, manually adjustable, or grilles with automatic control of the flow area (depending on the humidity of the exhaust air, CO content) are installed on the ventilation stacks.₂). It is possible to «stimulate» the exhaust with the help of one or several roof fans, according to the number of ventilation stacks, installed through silencers on the tops of the exhaust pipes. Finally, a common approach is to install wall models of fans with non-return valves in each bathroom and in the kitchen of the cottage, ejecting air from these rooms only during their use.— through openings in the outer walls (it is convenient if the fans turn on automatically, on a signal from a motion sensor, humidity or air quality). ATIn addition to wall fans in the attic, a permanently operating duct fan is placed, which draws polluted air through the roof to the street and at the same time ensures the minimum allowable air exchange in the living rooms of the cottage.

To lay ventilation ducts, it is enough to make a false ceiling around the perimeter of the room. Wall fans costing 0.5-4thousandrub. a lot on sale:Arktos» (Russia), Vortice (Italy), Silavent, XpelairDuctex (Great Britain), O. Erre (Italy), Soler Palav (Spain, trade mark Decor), «Ventilation Systems» (Ukraine, trade mark Vents). Duct fans cost 8-24thousandrub. offer Systemair and stberg (both— Sweden) Xpelair, O. Erre andetc. Among the roof fans, one can note the Fenco (Uniwersal) model, which provides an exhaust capacity of up to 180m³/h when the electric motor is on or works as a deflector (the fan impeller is designed in such a way that it does not interfere with the free exit of ventilation air).

We solve environmental problems

Many owners of cottages adjacent to freeways are seriously thinking about changing their place of residence as soon as possible. Dust, noise and unpleasant odors inevitably enter the house. But you can protect your home from them by tightly closing plastic windows and doors with a hermetic porch, and to organize air exchange, use a mechanical supply and exhaust ventilation system, which will ensure that a sufficient amount of fresh air cleaned of dust and “aromas” is supplied to the rooms and the exhaust air is removed from the cottage air.

Fresh air is supplied to the supply unit from the side of the facade, remote from the road Bsmall houses install mechanical supply and exhaust ventilation systems based on supply units (from 2-3thousandRUB/m² house area). Through an insulated channel that communicates with the street, they take in fresh air, clean it from dust and heat it up to a “sanitary” standard (17C), after which they are sent to all rooms through a network of air ducts laid behind a false ceiling or false walls. Air extraction, and therefore the removal of water vapor and other airborne contaminants, is carried out through ventilation ducts in the bathrooms and kitchen. In addition, in order not to «overload» the exhaust system of the house, a through hole is made in one of the non-residential premises in the outer wall, which is closed with wall-mounted gravity shutters that open when excess pressure occurs in the rooms, or equipped with an exhaust fan. Installation performance— from 150m³/h They can be placed in attics, basements or outdoors.

Mechanical supply and exhaust ventilation system based on a supply unit and a roof exhaust fan in a one-story house Such a ventilation system is capable of ensuring high-quality distribution of supply air in rooms at a minimum speed. The level of purification from contaminants can be very high (especially if carbon filters, bactericidal lamps, HEPA filters, etc. are used). ToThe disadvantages include increased energy consumption during the cold season with electric air heating. It is cheaper to operate air handling units with a water heater connected to the boiler. Note the inflows of Rover (Germany), Amalva (Lithuania), «Arktos«, «Ovik», «Engineering equipment«, «veza» (all— Russia) andetc. Network equipment for creating a system (air ducts, ventilation grilles, etc.) is in stock Systemair, stbergDiaflex (Sweden) andothers

Mechanical ventilation system based on an energy-saving air handling unit with a plate heat exchanger. Provides an influx of fresh air into living quarters and removal of exhaust air from bathrooms and technical rooms. If the cottage, in addition to environmental problems, is also experiencing a shortage of energy resources, the situation can be saved by a supply and exhaust ventilation system based on an energy-saving supply and exhaust unit. It will save 20-86% of the energy spent on heating the supply air during the cold season, due to the heat of the exhaust air. Energy saving is achieved through the use of a plate cross-flow heat exchanger, a rotary heat exchanger or an air heat pump in the supply and exhaust ventilation unit.— air». When installing the system, you will need to place two networks of air ducts in the house— supply and exhaust, with the help of which all the premises of the house will be connected to the supply and exhaust unit, as well as 2 times more than in the case of a system based on the supply unit, the number of ventilation grilles. Noise from air flows is eliminated by duct noise absorbers and flexible air ducts.

In the market of air handling units with a plate cross-flow heat exchanger, mainly imported equipment is represented: VVX, Maxi (Systemair), Caup (Shuft, Norway), UR (Aermec, UK). Particularly noteworthy are products with cellulose-based heat exchangers: VAM (Daikin, Japan) and Lossnay (Mitsubishi Electric, Japan). Air handling units with a rotary heat exchanger— model ranges Rotovex and VR (Systemair), HERU (stberg), Caur (Shuft), Gold, BCEA (Swegon, Sweden). Russian equipmentare the «Climate» settings (B.B. Consulting). Solution for a house from 200m² with serious automation can cost 3-8thousandRUB/m².

• Source: Ideas for Your Home Magazine#107