Since the widespread adaptation of HVAC systems, most residential and commercial establishments today rely on recycled air circulating through the system. Although artificial ventilation provided by heating and air-conditioning appliances is efficient in controlling temperature and humidity, the main trade-off is the poor air quality. These HVAC systems cause bacteria to build up and circulate. Apart from the dirty air, most commercial establishments also use harsh fluorescent lighting which harms the productivity of employees.
A study conducted showed that in commercial establishments, employees work better when there is plenty of fresh air and natural light. Many establishments around the world, like the UK, are seeing the benefits of allowing natural ventilation through window controls in schools and offices.
Implementing natural ventilation
A well-installed natural ventilation system has several advantages compared with a mechanical ventilation system.
- Using natural forces through openings in the building will provide high ventilation which is also more economical.
- It is an energy-efficient and eco-friendly method of ventilation for months when heating is not necessary.
- Provides access to natural light
- Moderates indoor humidity levels
- Increases oxygen levels indoors
- Reduces contaminant build-up
- Better comfort levels for building occupants
A popular method of natural ventilation in large buildings is to place vents for hot air to escape through the ceiling and have sidewall openings at lower levels for air to circulate within. In other establishments like schools, high-level windows are another effective method of natural ventilation where manual window controls provide a convenient way to access the opening.
From a technical standpoint, natural ventilation is further classified as simple or high-tech. High-tech natural ventilation is typically controlled mechanically or using computers. Although a high-tech natural ventilation system has all the benefits of a simple ventilation system, it may also suffer from the same drawbacks as conventional mechanical ventilation.
Possible drawbacks of a natural ventilation system
There are many challenges to implementing a natural ventilation system:
- The variability of climatic conditions proves to be a difficulty since it is difficult to control natural ventilation because it depends on airflow rate and temperature. It is possible for an establishment to suffer from low airflow rate in some sections of the building, while other areas have a high airflow rate bordering on uncomfortable levels.
- Concerns about climate and security may lead to keeping the windows and vents closed.
- Natural ventilation depends on natural forces which are highly unpredictable.
- There are times when natural ventilation will not work as expected due to low airflow, poor maintenance, and inadequate management.
Most of these challenges can be overcome with a better design such as incorporating a hybrid ventilation system instead of one that is purely dependent on natural forces. It is also vital to consider the type of establishment because natural ventilation may not be the best option for health-care facilities where it is crucial to control the spread of bacteria, insect vectors, and air particulates. However, natural ventilation does provide a compelling advantage for commercial buildings, offices, schools, and even residences.