Ventilation in buildings is the movement of air into and out of a space. It can be done naturally, mechanically or through a mix of both.
Ideal conditions ensure optimum health, productivity, wellbeing and lower stress levels. But these conditions vary from region to region. Ventilation is a key factor in creating these conditions.
Design and placement of windows
A building’s ventilation can have a significant impact on its occupants’ health and comfort. In addition to providing fresh air, good ventilation can reduce indoor temperatures and vapor levels. It can also lower concentrations of pollutants in the air.
The placement of windows is a crucial aspect of the design and appearance of a building. Ideally, windows should be placed in areas that will provide a view, frame a natural feature or landscape, and allow a breeze to pass through the space. However, it is important to consider the building’s use and climate when determining window orientation.
Window placement can also contribute to energy efficiency by minimizing direct sunlight during the summer and enhancing passive heating and cooling. This can lead to significant energy savings and reduced reliance on mechanical temperature control systems.
When planning the location of windows in a new building, it is important to consider the function of each space. For example, a school’s classrooms may require high levels of natural light and good ventilation. Likewise, a hospital or office space may need to be highly durable and functional.
For buildings that are visible from the street, it is best to use a rhythm of windows that complements the overall architectural style. This will enhance the kerb appeal and contribute to the overall aesthetic of the building.
Stack effect
A natural phenomenon that can help or hinder building ventilation, the stack effect is caused by differences in air density. Warmer air has a lower density, so it naturally rises and displaces cooler air. This process can be seen in many buildings, especially tall ones, where there are multiple floors and open space between them.
It is possible to design a structure to take advantage of the stack effect and Bernoulli’s principle for natural ventilation. This involves placing openings for inlet and exhaust at the bottom and top of the building, respectively. Ideally, the size of these openings should be roughly the same, so that cool air is sucked in through low inlet openings and hotter air escapes through high outlet openings.
During the winter, this effect is enhanced by the fact that warm air has a lower density than cold air. The result is that the air pressure in the upper part of the building is higher than in the bottom, which causes a draft that lifts air out of windows and doors on higher floors.
The same effect works in reverse during the summer, when people open their air conditioning units to fill their homes with cool air. This air is denser than the warm, outside air, so it sinks to the bottom of the building. The air pressure in the basement is therefore lower than that of the attic, causing cool air to escape through recessed lights and other openings at the bottom of the house.
Solar chimneys
Solar chimneys are a type of passive ventilation system that can be used to improve natural ventilation in buildings. These structures are tall and wide, painted and glazed to encourage them to attract heat, which helps create an updraft that ventilates the building. They can be a cost-effective alternative to traditional mechanical ventilation systems, which require a lot of energy.
The design of a solar chimney depends on the climate and location of the building. The inclination position of the chimney, window-to-wall ratio, stack height, and cavity gap are important factors that affect the air flow rate and performance of the system. Other factors that can influence the ventilation rate include the amount of solar irradiation, air mass infiltration, and orifice size.
Several studies have analyzed the impact of solar chimneys on natural ventilation in multi-story buildings. The results of these studies show that a solar chimney can greatly increase ventilation rates, especially when combined with a ceiling fan.
Solar chimneys work by heating the air inside the structure, which makes it rise due to its lower density compared with the surrounding air. This air is then vented out of the top of the chimney. The process of convection then draws new air into the chimney, which continues to heat up until it reaches the vent and is vented out again. The resulting thermal buoyancy allows for effective and energy-efficient natural ventilation, even in hot weather.
Green facades
As the interest in sustainable design and green solutions grows, building designers are incorporating a new element into the elevation designs of their buildings: green facades. Also known as living walls, these greening systems are a new way to insulate buildings and ensure thermal comfort while providing a beautiful visual effect. The use of green facades has many benefits, including energy savings and air quality improvement.
The most important characteristic of green facades is their ability to absorb solar heat and to shade the outer surface of a building. As a result, evapotranspiration cools the microclimate of a building, reducing the temperature in its interior and saving energy in high summer temperatures. Moreover, these plants are an ideal solution for urban areas as they reduce the energy waste associated with air-conditioning appliances and provide cost savings in cooling and heating.
There are a number of different designs for green facades. Most of them involve growing plants on a support system. They are usually constructed as trellis structures or baffles and are attached to the facade of the building. In general, green facades should be attached in ways that leave some space between the structure and the wall to avoid damage and ensure good air circulation.
The main purpose of these structures is to create a sustainable, livable environment and to increase the amount of natural light in the rooms. This is achieved by using plants and trees that are adapted to the climate, soil and other environmental conditions of the location.