This article on ventilation in residential buildings identifies factors that affect indoor air quality, provides information on what affects air quality degradation, and possible solutions..
Today, homeowners pay great attention to the interior of their homes. When planning a new home or renovating an old one, they want to be sure that everything in the new home will be joyful and pleasant, functional and comfortable..
Homeowners everywhere have one goal – the home must meet the needs of their family. They agree to invest a lot in it, to purchase any equipment that improves the physical and psychological climate in the family..
However, arranging their life, residents of both old and new houses are often carried away only by the external attributes of the interior and risk losing sight of one hidden from view, but no less important component of comfort – air quality.
Anyone with a home and some experience in solving problems associated with it will agree that the basis of comfort is to a certain extent invisible factors. Invisible to the eye, but clearly felt.
Almost always, when cold weather forces us to stay at home, we feel painful sickness in homes that are very good to live in at other times. The air becomes somehow stale and humid, the feeling of mustiness does not disappear for a long time. This feeling of discomfort does not disappear even when the room temperature rises..
In most cases, this is due to the fact that the house “does not breathe”. Well-insulated and tightly sealed houses cannot get rid of excess moisture on their own.
Indoor air is contaminated by gas emissions, suspended solids and volatile organic compounds. With the exception of water vapor, these components of the air environment of the room do not visually manifest themselves in any way.
To restore the comfort of the room, it is necessary to reduce the humidity of the air, remove all solid particles from it and open access to fresh air. In short, in order to provide good air for your family, all living rooms in it must have good ventilation..
Humidity is necessary, but within certain limits.
Air humidity is determined by the amount of water vapor contained in it (water in a gaseous state). Absolute humidity is a physical term that defines the amount of water vapor contained in one cubic meter of air. This value depends on the air temperature, since the ability of air to hold water depends on its temperature. For example, on cold winter days, the air cannot contain much moisture. Frost dries up the air. The warmer the air, the more moisture it can hold. That is why hot July air can also be humid and “thick”.
With just 2.8 liters of water vapor (moisture), the relative humidity of the air is increased from 15% to 60% throughout a 93 m2 home. Relative air humidity is characterized by the percentage of water vapor in a given volume of air compared to the maximum amount of water that can be retained in this volume at a given temperature. For example, air at 50% relative humidity contains half of the maximum amount of water vapor that can be contained in it at the same temperature. The closer the relative humidity of the air approaches 100%, the more difficult it is to dry something in such air..
The concept of relative humidity is fundamental when comparing the humidity of outdoor and indoor air at different temperatures. For illustration, note that outside air at 0 ° C and 100% RH is completely saturated. However, when such air enters the room and heats it to 20 ° C, it can take in four more times more water vapor until it reaches the saturation point again. Outdoor and indoor air have the same relative humidity at different temperatures.
Causes of high humidity.
Air, both outside and inside, always contains a certain amount of water. Its percentage depends on a number of factors. Inside the room, moisture is created by the plants in it, due to the formation of steam during cooking, taking a bath, showering, when working with dishwashers and washing machines. A certain amount of water is released into the air from the construction materials of the house and furniture. Normal breathing of people and animals also contributes to the increase in air humidity. Excess air humidity is manifested primarily on the windows. With excessive long-term air humidity, moisture condenses on the windows in the form of water droplets, which flow down onto the windowsill and onto the floor. The problem of increased humidity in a room becomes more acute over time, as walls and in-wall insulation absorb water vapor accumulating in the air, especially in the bathroom and kitchen. The harmful effects of high humidity can even manifest itself in the form of black mold spots..
Pets, aquariums and self-defrosting refrigerators are additional sources of moisture.
Air containing too much moisture is harmful to human health. The human body feels the wet cold faster and stronger, in this case the cold “creeps to the bone” and the person shivers. The cold penetrates everywhere. You can escape from it either by raising the air temperature, or by putting on all the clothes that are in the house. Human health experts believe that bacteria can spread very quickly in a damp, poorly ventilated room. This significantly increases the risk of infection..
However, if the humidity in the room is too low, then the air becomes dry, which also affects health – a person’s nose either constantly “clogs up”, or it creates an itching sensation.
Another serious consequence of the periodic increase in indoor humidity is the gradual destruction of houses. This effect of moisture is often not immediately noticeable, but it is nevertheless present. The wall frame, especially near windows and in the bathroom area, as well as the roof are two areas in the construction of houses that are most strongly susceptible to the negative effects of excess air humidity in the premises.
In any residential building, all rooms are filled with myriads of air polluting microparticles and elements of the most varied kinds and origins. Most of them are invisible to the naked eye and do not pose any danger to human health if the indoor air is constantly renewed. For example, in summer, when the windows in the house are open and the house is blown by the cool evening breeze, the effect of these particles on the health of its inhabitants is completely insignificant, because they are largely dissolved in the stream of fresh outside air. However, in the cold season, the situation changes dramatically: air polluting particles become difficult to remove, since indoor air is not renewed sufficiently. At such a time, all these air pollutants constantly affect the human body and can affect its health, which should be the cause of concern for its inhabitants..
A well-known air pollutant is tobacco smoke.
A lesser known air pollutant is formaldehyde gas, which is released into the air from synthetic carpets, polyurethane foam insulation, interior decoration materials, furniture, curtains, etc. It is included in the list of authentically carcinogenic substances, has chronic toxicity, negatively affects the hereditary genetic and chromosomal mutation, respiratory tract, eyes, skin, reproductive organs.
Mercury from previously broken thermometers, fluorescent lamps and other devices does not disappear from the apartment, but accumulates under the floor. It can poison unsuspecting occupants. Nitric oxide is one of the gases produced by gas heaters, fireplaces, and wood- or coal-fired stoves. Other open-fire heaters, including water heaters and laundry dryers, are also sources of nitric oxide. Colorless and odorless, this gas can irritate the eyes and respiratory tract and can lead to chronic bronchitis.Home heaters using open flames, especially gas stoves, emit carbon monoxide during operation, which also affects the eyes and respiratory tract. … Carbon dioxide, like carbon monoxide, can cause headaches and nausea, and it also reduces the amount of oxygen in the blood, which in turn makes a person feel more tired..
Twenty-five years ago, the International Agency for Research on Cancer (IARC) began work to identify carcinogenic substances harmful to the human body. All carcinogenic factors evaluated by experts were divided into 4 groups. The first included factors that are undoubtedly carcinogenic, the second – potentially carcinogenic for humans, the third – factors that cannot yet be classified in terms of their carcinogenicity for humans, the fourth – safe for human health.
Some carcinogens found in home air:
- the first group: asbestos, benzene, vinyl chloride, cadmium and its compounds, radon, soot;
- second group: benzopyrene, acitataldehyde, N-nitrosodimethylamine, polychlorinated biphenyls (PCBs), styrene, pentachlorophenol, dichloroethane, formaldehyde, chloroform, polycyclic aromatic hydrocarbons.
- The air of the room always contains various solid particles and microorganisms in suspension, which are carried into the house by humans, animals, and also penetrate into it from poorly maintained ventilation shafts and air ducts. These elements are also invisible to the naked eye, and some of them are microbes, which, with an increase in air humidity, begin to multiply rapidly. In poorly ventilated rooms, these microorganisms can cause an unpleasant odor, a feeling of discomfort, slight discomfort in the form of sneezing attacks, or even lead to the appearance of various bacterial infections.
The latter of the indoor air pollutants found in the emissions of various chemicals used in cosmetics and shampoos, various cleaning agents, pesticides and other chemical and biological agents. Frequent use of these products in poorly ventilated areas causes allergic reactions, irritations and various respiratory disorders. Researchers have found that toxic substances found in tap water in minimal (safe) concentrations are released from the water during washing or washing. A dishwasher is an especially unsafe unit, since during high-temperature washing ideal conditions are created for a variety of chemical reactions, the products of which enter the atmosphere of the home.
This list of residential air pollutants is not provided to cause unnecessary concern. However, as a result of the lack of air circulation, poor ventilation of the premises and insufficient supply of fresh air, conditions are created under which these harmful substances can act on a person intensively and massively, posing an immediate threat to his health. WHO experts concluded that “the air quality characteristic of the indoor environment of various buildings and structures is more important for human health and well-being than outdoor air quality”.
Effective room ventilation.
Highly efficient ventilation systems provide living spaces with very high quality air.
Striving for the best in one area often creates problems in another. The same happens when designing the insulation of houses under construction. The almost perfect degree of insulation and the dense construction of the dwelling are good in order not to let cold air from the street into it, and thereby keep its inhabitants warm. However, together with the heat, a tightly closed house does not let out stale air, excess moisture and its various pollutants. As a result, the “atmosphere” of such a house becomes harmful both for the people living in it and for itself. To eliminate problems associated with danger to human health, humid, spoiled air must be removed outside and replaced with fresh air. The newly supplied air must penetrate into all the rooms of the house so as to ensure its complete and effective ventilation.In short, throughout the year we must do what nature does for us during the summer months..
Each person’s breath and the usual evaporation of moisture through the pores on the skin can add up to 4.3 liters of steam per day to the air. Where the breeze of freshness disappears, highly efficient ventilation systems can help home owners protect the health of loved ones, preserve and even increase their money investments. In the cold season, when the windows are tightly closed for the whole winter, supply and exhaust duct ventilation systems will help to provide living quarters with very high quality air. These systems are specially designed to quickly remove moisture, stale air, all kinds of pollutants directly from their sources through an extensive ventilation network. In addition, these efficient ventilation systems deliver fresh air throughout the home through an extensive intake and distribution system..
As an additional function, such a ventilation system helps to maintain heat inside the modern home: before the cold fresh air taken from the street is distributed throughout the premises, it heats up. Preheated air drastically changes the level of comfort in the home, as it does not lower the temperature of the interior. Thus, by continually or periodically renewing the air as needed, these energy-efficient ventilation systems can solve the air quality problem in your home once and for all..
Good air quality in your home is one of the most important factors in keeping your family members healthy. Poor indoor air not only affects well-being, but can be the cause of disease. Excessive humidity is harmful to health, so excess moisture must be removed from the room. In addition, the removal of excess moisture from all rooms has a beneficial effect on the safety of the building structure of the house, since it is not exposed to dampness..
In cold weather, when neither door nor window is opened to freshen the air, the home owner can rely on a high-quality ventilation system installed in his home. In hot weather, when the air conditioners are turned on, a high-quality ventilation system can compensate for the lack of outdoor fresh air..
Be aware that there are highly efficient ventilation systems specifically designed for ventilation and air conditioning that perform these functions regardless of the season or any other circumstance. The experts in ventilation systems sent to you will solve your specific problem and recommend either an air heat exchanger or a ventilation unit with a heat recuperator (heat recovery unit).
Whether you recently bought your home, or are a longtime homeowner, new or refurbished home, you can consult with a specialist for any ventilation in your home. All your family members rely on your intuition to find a comfortable, enjoyable and “healthy” home. Don’t let them down!
Need help choosing the best ventilation system for your application? Would you like to receive more detailed information on the installation of the system or on the warranty? Do you have a question about how to make the fresh air invisible? Are you worried about the noise level of your ventilation system? How can the performance of the existing ventilation system be improved? You can always rely on the qualified help of experts from specialized professional companies.
The article was prepared by the employees of the Ventrade company