Every household has its own energy pulse. Just as people need oxygen and movement to live and work, so must a household have a healthy microclimate to provide a good environment for its occupants.

People spend most of their day indoors and Eurostat data shows that the number of people working remotely has almost increased by half in the last decade. In Latvia, 86% of the people surveyed use hybrid working, which makes us think even more about the importance of providing a supportive household environment. The experts at the Elektrum Energy Efficiency Centre encourage you to take care of your household environment in order to maintain conditions that support your health and work capacity.

Indoor environmental hazards that adversely affect the household environment include biological and chemical pollutants, as well as poor ergonomics, lighting and physical interior design. These hazards cause and intensify a range of adverse health effects, from asthma to sick building syndrome (discomfort or noticeable deterioration in health experienced by building occupants, attributed to the length of time spent in the building, but the specific cause or cause of the illness cannot be identified) and finally to cancer.

The key to a favourable indoor microclimate is natural light, fresh air, optimal temperature and humidity levels, interaction with nature. How does this play out and fit into everyday life?

Natural light

Natural light improves mental health, and sunlight not only provides a sense of well-being and vitamin D, but also acts as a natural disinfectant in the household, reducing microbial growth. Using daylight as much as possible and reducing artificial lighting can also save on electricity consumption.

It is therefore particularly advisable to open curtains and blinds to let light in when waking up in the morning. Mirrors and other reflective decorative elements, as well as light tones, will also help to add light to the household.

Fresh air

Fresh air is one of the prerequisites for good health, as oxygen plays an important role in physiological processes. However, another very important factor related to air quality is often overlooked: the concentration of carbon dioxide, or CO₂, in the room. This is the most widely used parameter for indoor air quality. If there is insufficient air exchange, indoor oxygen levels decrease and the concentration of exhaled gases increases. In the long term, this can cause significant damage to health, while in everyday life it can lead to drowsiness and breathlessness and contribute to fatigue, reducing mental efficiency by 50–70%.

CO₂ concentration is measured in parts per million (ppm), and indoor CO₂ concentrations of up to 1000 ppm are considered acceptable. CO₂ levels can be measured by multifunctional measuring devices available in shops, which also measure the temperature and humidity in a room.

Indoor smoking, the use of household cleaning chemicals, the burning of fireplaces or stoves, the use of gas cookers and other factors also impair air quality and should be avoided as much as possible.

The simplest way to improve indoor air quality is to ensure that rooms are ventilated. During ventilation, it is advisable to leave the room and open the window fully for a short time to avoid catching cold, rather than leaving the window in ventilation mode for long periods. In addition, rooms should be ventilated several times a day.

From an energy efficiency point of view, it is also advisable to turn off heating appliances when ventilating rooms during the cold season. For radiators with heat control, it is recommended to select the mode indicated by an asterisk (*) and to restore the set mode after ventilation.

However, in summer, it is best to ventilate early in the morning before the rooms have warmed up, and occasionally during the day. Just as it is recommended to switch off heating appliances when ventilating rooms in winter, in summer the air conditioner should be switched off when ventilating rooms to avoid wasting electricity.

Not too wet, not too dry

According to the World Health Organization (WHO), 10–50% of indoor environments in households in places such as Europe, North America, Australia, India and Japan are humid.

Excessive indoor humidity can cause building damage, chemical emissions from building materials, and contribute to microbial growth and other potentially problematic effects. For example, mould species are more likely to occur in damp indoor environments and potentially release allergens, mycotoxins and unpleasant odours into the air.

Weather conditions also affect indoor humidity levels, for example, humidity levels can increase during a rainy summer period. If the humidity level in a room is above 60%, it would be advisable, for example, to move houseplants, which give off extra moisture, to other rooms and to avoid drying laundry, at least in the rooms where you are most often present. In dry weather, it is advisable to dry laundry outdoors if possible.

Note that indoor activities such as showering, cooking or washing the floor also release moisture very rapidly and concentratedly, but for short periods.

To ensure a comfortable and safe indoor climate, the relative humidity shall be within a certain range. The recommended indoor humidity is 40–60%. The humidity can be measured using a hygrometer, which can be bought in household goods shops.

Care should be taken to ensure that the air in the room is not too dry, both during the summer season when various air-cooling devices are used intensively, and during the heating season when heating is used. If the humidity level does not exceed 30%, the air is considered dry. This can have an adverse effect on the skin, respiratory tract, nasal mucosa and eyes, causing irritation. The simplest way to humidify the air without the need for special equipment is to hang a damp cloth in the room, which will release moisture over time.

The use of plants is recommended to improve air quality. Not only do they brighten up rooms and improve well-being, they also act as natural air filters, absorbing airborne toxins. NASA has compiled a list of houseplants that have proven their performance in this respect: English ivy, variegated sansevieria ‘snake plant’, heartleaf philodendron, red-edged dracaena, etc., which you can read more about here.

There are also a variety of microclimate devices such as humidifiers, dehumidifiers, with additional functions and options such as hot/cold steam, addition of essential oils, etc., which will further improve the household environment and contribute to the comfort of the occupants.

Optimal temperature

If the room temperature can be controlled, you can create an almost ideal microclimate, which will not only save energy and reduce your heating bill, but will also benefit your health. The optimum indoor temperature in autumn and winter is between +20 and +22 °C during the day. However, at night, it is recommended to lower the temperature by 3–4 °C to ensure better sleep and boost immunity.

If possible, adjust the temperature for each room:

• in the kitchen, where extra heat is released during cooking, keep the temperature between +19 and +21 °C,
• in the bedroom – from +17 to +18 °C,
• in the living room and bathroom – from +20 to +22 °C.

Just a slight reduction in temperature can save 10% of energy! And when you leave the house, lower the indoor temperature to +16 °C.

Effective air cooling

In summer, an air conditioner will be essential to alleviate the heat. To cool your rooms efficiently and safely, here are a few tips to follow:

• It is advisable to lower the room temperature by no more than 3–4 °C compared to the outside air temperature. A higher temperature difference can cause discomfort, such as sore throats, runny noses, headaches, dry eyes and increase electricity consumption.
• When the air conditioner is running, windows and doors should be closed to prevent warm air from entering the room and re-heating it.
• It is preferable to start cooling the room early in the morning, but during the day you only need to maintain a comfortable temperature and to shut the blinds and curtains in good time.
• Efficient operation of the air conditioner can be achieved by programming its operating time (if the appliance has this function).
• To ensure good air circulation, move obstacles, i.e. furniture or plants, which block the flow of cooled air.
• Do not place equipment near the air conditioner that gives off heat when running, making the air conditioner think that the room is warmer than it actually is.

Clean and green environment

It's not for nothing that there is a saying: "clean house, clean mind". And really, how nice it is to remember the feeling you get after a general cleaning of your household or after freshly washed and air-dried laundry!

It also has an impact on your health, so it's important to keep your household clean and to try to clean it with eco-friendly cleaning products and detergents that are free from chemicals.

Why is this important? Everything we use, clean and wash goes down the drain, into the sewage, into the groundwater and also into the water that we then use again in our daily lives, so it makes you wonder, do we want to use chemicals?

It is also possible to make cleaning products from household products such as baking soda, which is a great bathroom cleaner, and citric acid combined with various essential oils.

The experts at the Elektrum Energy Efficiency Centre invite you to take a look at EsmuEfektivs.lv for other useful tips on household energy efficiency.