Standard diagrams and rules for drafting a ventilation system in a private house
In multi-apartment buildings, the presence of a ventilation system with a natural impulse for air circulation is a necessary condition, without which a residential building will not be put into operation.
However, in private construction, the organization of air exchange is often remembered only with the appearance of unpleasant odors and fungal mold on the walls. A well-designed ventilation scheme in a private home will help solve this problem.
In this material we will talk about the features of natural and forced ventilation and the principles of its functioning. And also about how to correctly design an air exchange system in a private house.
The content of the article:
Why does a building need ventilation?
The use of modern materials and various external enclosing structures of a cottage/house in construction complicates the natural air exchange between rooms and the street, and sometimes even blocks it. Thanks to the internal and external insulation, the installed plastic windows of the building become airtight.
Such measures help preserve heat and save energy resources, but greatly impede the flow of fresh air. To correct this typical situation, it is necessary to organize an effective air circulation system.
In a building, ventilation is needed so that fresh air regularly enters the bathroom, bedroom, living room and kitchen, not through open windows and doors, but through special devices - anemostats and air diffusers.
A constant flow of air into the house will provide comfortable conditions for long-term living of people and maintenance of plants, as well as for the full functioning of all technical systems.
Ventilation is also necessary to maintain optimal environmental parameters for the safe operation of various building structures, wooden furniture and interior items.
The circulation of air flows must be organized not only in living rooms, but also in utility rooms - bathrooms and toilets, in the kitchen, in the boiler room and basement.
A high-quality ventilation system helps quickly remove excess moisture and heat. Along with the exhaust air, harmful microorganisms, accumulated dirt and dust are simultaneously removed from the premises.
That is why it is important to think through all the details of the utility network at the design stage of a residential building: ventilation in the kitchen make it more powerful than in other rooms, correctly select the functional elements of the ventilation system to ensure optimal oxygen levels in the interior spaces.
Methods for organizing air exchange in the house
There are different ways to ensure air exchange in a residential building - from periodically briefly opening doors and windows to installing multifunctional systems for preparing and delivering clean air to each room.
From the point of view of ventilation, a healthy and comfortable atmosphere in the house is formed not only due to the composition of the air.Its temperature, uniformity of distribution and mobility play an important role.
The influx of cool air can create a powerful convection current, which will be perceived by humans as an unpleasant draft. As a result, even at normal temperatures the room will be uncomfortable.
The ventilation system in the cottage kitchen, made from wooden beams, also seemed as simple as possible. Leaky doorways and window blocks contributed to the continuous circulation of air currents in the house.
All these methods are still used today in small one-story buildings. There is quite enough natural air ventilation there. But if we talk about large and spacious private houses, then it is impossible to do without additionally installed central air conditioners and fans.
Types of ventilation systems
According to the basic requirements of hygienic and sanitary standards, the ventilation performance of any type should be:
- 3m3 per hour per 1 square meter of area for living rooms;
- 25 m3 for separate sanitary facilities;
- 50 m3 for sanitary facilities.
The amount of fresh air that needs to be supplied to different rooms depends on a number of other factors - the number of people, the nature and frequency of work performed, the concentration of harmful substances.
In residential premises, 35 m is introduced per adult3 air, for children under 10 years of age the norm is 15-20 m3 per hour, for slightly older children - 25 m3.
A designed ventilation scheme in compliance with these parameters will guarantee a regular, stable flow of fresh air and comfortable living in a private home.
There are three types of air exchange systems:
- natural - with natural stimulation of air flow circulation;
- mechanical — with forced intake and exhaust of air;
- combined - with partial use of mechanical exhaust and natural intake of fresh air masses.
It is necessary to organize a continuous automatic supply of clean air in the house. Only the intensity of inflow and removal can change.
But on the other hand, the forced mechanisms involved greatly simplify the ventilation of residential and auxiliary premises.
Read about how to correctly calculate the ventilation system for a home Further.
Natural ventilation in the house
To organize natural air exchange, the concept of vertical ventilation ducts is used. One end is mounted indoors, and the other is brought out slightly above the roof of the building.
Since the air temperature in the house usually differs from the outside temperature, warm currents gradually rise through the exhaust duct. A fresh portion enters the rooms from the external space through window and door blocks.
Among the main advantages of such a system are simplicity and minimal costs for arrangement, saturation of rooms with natural air, and independence from electricity.
But there are also significant disadvantages. Thus, natural ventilation in a private building will only work until the air temperature outside exceeds 12 degrees Celsius. At high rates, the hood will not be able to work fully.
At first glance, this situation seems ideal for winter, but there is a drawback that simply cannot be ignored. If there is a significant temperature difference between the outside and indoor air, the system will start working faster. All the heat will literally fly freely into the chimney.
Therefore, residents of cottages and private houses spend more energy resources on heating than normal climatic conditions require.
To organize a ventilation system of this type, separate air ducts are laid from each utility room into a common shaft. From the kitchen you need to lay two channels - one from the exhaust grille under the ceiling, and the other from the kitchen hood.
It is also necessary to pay special attention to all rooms completely/partially located below ground level in the house. Toxic radon accumulates in them. To reduce the amount of dangerous gas, a powerful exhaust duct should be installed.
In addition, you need to take care of reliable waterproofing of the basement. After all, even the most effective supply and exhaust system will not cope with its tasks if the basement of a private house or cottage is always damp.
How can you improve efficiency?
There are several ways to help improve the performance of a naturally driven air exchange system:
- install a special valve at the entrance to the channel;
- install grilles with valves on the inflow and outflow channels;
- use a deflector.
The valve, equipped with automation, responds to even slight changes in air humidity. It is mounted at the entrance to the air duct inside the building.When the humidity in the room increases, the automatic relay is activated and the internal valve opens the channel more.
If the indicators decrease, the device closes the entrance. The sensitive element is a sensor that picks up signals from the environment. It is installed outside the house.
In winter, the valve must be additionally closed. This will minimize the entry of cold air into the residential building. However, installing such a device will not cover all the shortcomings of natural ventilation.
Another effective method is to install grilles with valves on the channels for the inflow and removal of air masses. They can only be controlled manually. The valve position must be adjusted at least once a season, when the outside air temperature changes.
Wind can also increase draft in exhaust vertical ducts. To use natural force, a deflector is placed on the top of the pipe - a special device that protects the air duct from debris and precipitation, and also increases draft.
The deflector splits one air stream into two or even more at different speeds. It creates a vacuum, which, in turn, increases the pressure drop in the pipe. As a result, the duct extracts exhaust air better.
Features of forced air exchange
If natural ventilation does not provide complete air renewal, a powerful supply and exhaust system is installed in a private house.
It helps balance the air currents that circulate between rooms and the outside environment continuously. Such ventilation guarantees a stable supply of purified fresh air and removal of contaminated air.
Description of mechanical ventilation option
Modern multifunctional supply and exhaust ventilation units make maximum use of the energy of the supplied air flows and convert it into heat.
Such systems deeply clean the supply air, completely filtering it from dust, various allergens, bacteria and other harmful microorganisms.
Additional processing is created using filtration equipment, highly effective noise absorbers, ionization and humidification devices, and sometimes flavoring devices are used.
The functional elements of a system with forced air exchange are filters and recuperators, fans, hoods, control devices and, directly, the ventilation unit.
Built-in electronics make it possible to selectively set optimal user operating modes of the system in terms of temperature and humidity, and over time. Remote controls and smart controllers greatly simplify operation.
Mechanical ventilation helps prevent the formation of unpleasant odors in the kitchen, prevents the appearance of dampness and the spread of multi-colored mold, solves the problem of constant humidity in the bathroom and condensation on the surface of the heated floor, double-glazed windows, and door blocks.
Modern multifunctional forced ventilation systems are often combined with intelligent control and monitoring systems. Such measures optimize the operation of the equipment of all installed engineering systems in the house and make it possible to organize user-friendly remote control of equipment via the Internet.
Mechanical ventilation with heat recovery
In schemes with heat recovery, a stationary supply and exhaust unit is responsible for air exchange in the building. Air from the environment enters the system, after which it is cleaned of dust and impurities by a filter and sent for main heating to the recuperator.
The air masses are heated to the required temperature in an electricwater heater and are distributed throughout the house through durable galvanized steel ventilation ducts.
A heat recovery system will ensure high air quality in a residential building all year round. At low speeds of operating fans, supply and exhaust stationary units operate almost silently.
Automation makes it possible to flexibly control the operation of equipment: regulate air flow, set a comfortable temperature, change the speed of air flows.
Maintenance of such an installation consists of regularly changing filters. It is recommended to replace new elements for purifying air from dust once a quarter.
System without heat recovery
To organize functional supply and exhaust ventilation without an air recuperator, several exhaust systems and a central supply unit are used at once. Street air is heated or cooled, then purified in a filter, after which it is distributed through a network of channels to living rooms.
Removal of waste heavy air masses is carried out using hoods in utility and technical premises. Such systems are made partly natural and partly forced. They operate due to natural draft and thanks to duct fans.
Supply and exhaust circuits without heat recovery provide heating and purification of the air entering the house, but spend a large amount of energy on the constant processing of air flows.
Combined system type
Combined ventilation is implemented mainly in the form of a scheme with natural inflow and mechanical, that is, forced, exhaust of waste masses.
Fresh air enters the rooms through valves due to the vacuum created by exhaust fans. In this case, preliminary heating of the supply air masses is not performed. But this is not a problem if you install a correctly selected heating element under the valve - an open radiator.
Mechanical exhaust in a private house is performed by fans, usually duct fans.There may be several of them, but sometimes one is enough.
To ensure efficient air circulation, exhaust fans must run continuously. In order to save energy resources, speed controllers with automatic/manual control are connected to the system.
Experts characterize combined ventilation as functional, relatively inexpensive and easy to use. You won't need a lot of space to install related equipment. In addition, all functional elements require minimal maintenance.
Among the disadvantages of the combined type of system, it is worth noting the lack of filtration and heating of the supply air, as well as minimum air exchange rates.
Rules for drawing up a ventilation project
The full operation of the ventilation system directly depends on the accurate calculation of technical parameters and a well-designed design for the circulation of air flows in the house.
Developing a layout of equipment and pipe routing makes it possible to include channels for exhausting stale air into the project. In addition, it will be convenient to adjust the height of the ceilings in the rooms, taking into account the additional space for laying outgoing pipes.
If you install ventilation during the redevelopment/reconstruction of a building, you need to specially groove the walls for ventilation ducts or install massive attached shafts, which do not look aesthetically pleasing at all.
It is at the stage of engineering design of the air exchange system that basic technical solutions are determined:
- method of air flow distribution in the house;
- type of ventilation and exhaust shafts;
- availability of filtration equipment.
However, when calculating the ventilation system, infiltration is not taken into account, since the contribution to the circulation of air flows is negligible.
The air quality in residential and utility rooms is influenced by many factors. When developing a ventilation project, in addition to the design features of a private structure, various generally accepted standards and objective indicators are taken into account. The personal preferences of the home owner and the available budget also play an important role in this process.
The design of ventilation systems is carried out according to the following plan:
- At the initial stage, technical specifications are drawn up.
- The second step is choosing the optimal air exchange concept in a private home.
- The next stage is the development of a diagram with calculation of the level of noise created by ventilation, calculation of the cross-section and selection of air ducts with the required parameters.
- Next comes the preparation of the drawing for approval by the customer.
- The last stage is the final design and delivery of the finished ventilation scheme.
It is necessary to exclude situations where, in order to carry out repair work or periodically inspect equipment, it is necessary to dismantle parts of building structures or decorative finishing. Therefore, it is better to place filters, heaters, fans and other system components in a special technical room.
This will also solve the problem of organizing effective noise insulation of an operating ventilation unit.
If you do not follow templates, but develop an individual concept for arranging ventilation for a specific construction project, you can ensure a stable supply of clean air to all interior spaces and exhaust of polluted air.
When developing a ventilation scheme, you need to focus on some technical features:
- the volumes of exhaust and supply air masses must be balanced;
- fresh and clean air is supplied only to living rooms, and exhaust air is removed from utility rooms;
- It is not allowed to combine exhaust hoods from the kitchen and bathroom into one ventilation duct;
- the air flow speed in exhaust pipes and main air ducts should not exceed 6 m/s. At the exit from the grate, the maximum indicator is 3 m/s;
- ventilation shafts that run along the street must be insulated with insulating materials at least 5 cm thick.
Experts recommend choosing a basic supply and exhaust circuit. Ventilation of this type will effectively cope with the supply of fresh air and filtration of internal air.
The correct approach to the circulation of air masses will help create a favorable and comfortable microclimate in the house.
Conclusions and useful video on the topic
The video explains why ventilation is needed in every private house and why mixing of supply and exhaust air flows should not be allowed:
This video clearly shows how to properly organize the inflow and evacuation of air with the natural ventilation scheme of a country house:
Video about how supply and exhaust ventilation of sufficient power with thermal energy recovery functions using the example of the profi-air system from the German manufacturer FRANKISCHE:
Having studied the principles of operation of ventilation systems, it is quite possible to properly organize air exchange in a small one-story building on your own. However ventilation design and installation in spacious country houses it is better to entrust it to professionals. After all, the installed system must not only work, but also cope with planned tasks.
Properly equipped ventilation will solve the problems of standing air and the unpleasant feeling of mustiness in a private home.
Do you have any questions, found any shortcomings, or want to share useful information on arranging ventilation in a private home? Please leave your comments, ask questions and share your experience in the block below the article.
Good afternoon. I am building a house in Sochi, three floors plus a basement with an area of 700 sq. m. I am looking for a ventilation and air conditioning system with a balance between price and quality. Thank you.