Ventilation, more often than not, holds the key to good health in modern homes and is a crucial factor for home-buyers. Fraught with designer snafus, homes today severely lack air passages and ventilation vents that take its toll on the health of inmates over a period of time.
It is very important for indoor stale air to be flushed outside and replaced with fresh outdoor air. The process has twin benefits. During warmer months, ventilation helps keep attics cool. During the cold, ventilation reduces moisture to help keep attics dry. Nowadays, realising the vitality of air-circulation, more and more homeowners have been installing ventilators in their homes.
Before getting into the intricate details and benefits of ventilation, one needs to understand the basic terms attached with this system. For a layman, some of the common terms used with ventilation systems, such as balancing, ventilator core and pre-filter can be quite mind-boggling. ‘Balancing’ a ventilation system means matching incoming airflow with the outgoing airflow.
When introducing fresh air into a home, it is important to exhaust the same amount of air to avoid positive or negative pressure in the home. An indication of an unbalanced home is a rush of air when a door is opened. Unbalanced homes can also cause excessive energy consumption. In the ‘ventilator core’ the heat transferred through the intake and exhaust streams is stored. This is accomplished mechanically through natural heat transfer. The core of the ventilator can be removed and washed if needed. A pre-filter is a filter attached to the ventilator core to prevent unwanted debris from clogging the air passages.
The benefits of ventilators are very basic in nature. It helps to control the drying process when building a new home or making improvements to an existing one by expelling excess moisture. It also reduces fumes from new carpets, adhesives, paints and stains. In colder regions, it acts as a silent fan, removing excess moisture that could condense on windows in winter.
Ventilation plays an important role in both summer and winter seasons. During summer, radiant heat from the sun increases the roof temperature and thus heat travels into the attic. As heat builds up in the attic, it radiates to the attic floor and then into adjacent living areas thereby increasing the home temperature gradually. The longer the hot, sunny weather lasts, the more uncomfortable it becomes in the home.
That is because an unventilated or inadequately ventilated attic seldom loses enough heat overnight to compensate for the heat gained during the day. Ventilation cannot eliminate the transfer of heat from roof to attic, but it can minimise the effect. To do that, a well-designed system must provide a uniform flow of cool air along the underside of the roof covering. That steady flow of air carries heat out of the attic before it can radiate to the attic floor.
Uniform flow of air is an important consideration for proper ventilation. This implies that intake and exhaust vents must be balanced for both position and airflow capacities. Otherwise ‘hot spots’ can develop under roof covering that will reduce the efficiency and effectiveness of ventilation system.
With the advent of winter, the temperature drops. In winters, the conditions get reversed - heated indoor air travels from the home into the attic - along with moisture. Problems arise when the warm, moist air from the living quarters moves toward the attic where the air is cooler and drier. This leads to moisture accumulation. As with heat build-up, moisture build-up has long-term effects.
The structural elements of the house absorb moisture leading to wood rot and the deterioration of roofing materials. Moisture is also likely to soak into the attic floor and eventually into ceiling materials, causing water stains and paint damage in the rooms.
Although the problems of attic heat and moisture have different causes, the solution is very much similar - a high-efficiency ventilation system that allows a uniform flow of air to sweep the underside of the roof covering. In warmer months, such a system exhausts hot air from an attic; in the colder months, it exchanges warm, moist air with cooler, drier air.
An interesting fact is that the U.S. Environmental Protection Agency has listed indoor air quality as one of five top environmental issues. Experts in this subject recommend a complete fresh air exchange in the home every three hours.
But, in modern-day homes, fresh air exchange can take as long as 10 hours. Although a well-insulated house means greater energy efficiency, it does not always allow much fresh air in or stale air out. This lack of fresh air exchange leads to odours and at the same time bacteria thrives. Opening windows is not always the logical solution for getting fresh air circulating.
Doing so, will put more load on the heating and air conditioning systems that have to work overtime to compensate for the temperature fluctuations caused by open windows.
Bringing in fresh outdoor air, without compromising on energy saving and comfort-level temperatures indoor is the ideal solution. Ventilation helps in achieving exactly this.