Air Ventilation

Without mechanical ventilation to provide fresh air, moisture, odors, and other pollutants can build up inside a home. Mechanical ventilation systems circulate fresh air using ducts and fans, rather than relying on airflow through small holes or cracks in a home’s walls, roof, or windows. As homes are becoming “tighter”, i.e., decreased heat transfer through better insulation, wrapping, vinyl e-glass windows, and improved weather stripping; indoor air is trapped. Homeowners can breathe easier knowing their home is more efficient but without proper ventilation will breathe unhealthy air.

BENEFITS OF VENTILATION

• Better Indoor Air Quality. Indoor air can be many times more polluted than outdoor air, and he average American spends 90 percent of the day inside. Ventilation systems can significantly improve a home’s air quality by removing allergens, pollutants, and moisture that can cause mold problems.

• More Control. When homes rely on air flow through walls, roofs, and windows for ventilation, there is no control over the source or amount of air that comes into the house.In fact, air leaking into the house may come from undesirable areas such as the garage, attic, or crawl space. Mechanical ventilation systems, however, provide proper fresh air flow along with appropriate locations for intake and exhaust.

• Improved Comfort. Mechanical ventilation systems allow a constant flow of outside air into the home and can also provide filtration, dehumidification, and conditioning of the incoming outside air.

HOW VENTILATION SYSTEMS WORK A variety of mechanical ventilation systems are available to select from, based on local climate and the home’s heating and cooling system. In addition to one of the primary systems described below, “spot” ventilation fans should also be provided for kitchens and baths to remove the concentrated moisture and odors that can occur in these rooms. The typical systems are used in the Greater St. Louis area. Note: Allow Hoffmann Brothers Heating and Air Conditioning help you with your IAQ needs. Get the peace of mind you deserve.

• Whole-House Exhaust System. Indoor air is continuously exhausted to the outdoors with one fan often located in the main hallway. Because indoor air is continually drawn out, the home becomes slightly depressurized unless windows are opened. These systems are best used in the Spring and Fall, when stale air can be exhausted while bringing in fresh cooler air. There are two problems with these systems:

1.If you suffer from outdoor allergies, outside air can be your worst enemy. Please see Air Purification and Air Filtration. Life doesn’t have to be miserable in your own home.

2.These systems are typically not appropriate for hot, humid climates, which is common in our area. You run the risk of drawing hot humid outdoor air that may cause moisture problems. In the Greater St. Louis area, moisture problems may lead to mold issues. Our area is best supported by the Lennox Energy Recovery Ventilator (ERV). With the ERV, equal quantities of air are brought into and sent out of the home. This is usually achieved using two fans—one to bring fresh air in and another to send indoor air out. ERVs transfer heat and moisture between the exhaust air and incoming air. This provides additional savings in the summer by reducing the moisture content of the incoming air that would otherwise have to be dehumidified with the cooling equipment or a dehumidifier. ERVs also provide additional comfort in the winter by adding moisture from the outgoing air to the incoming air to help avoid excessively dry indoor conditions. Click Lennox ERV to find out more on how this system can help your stale air problem.

Attic Ventilation Systems: Natural and Fan Ventilation. At first it may seem odd to add insulation for warmth and then purposely allow cold air to enter the attic through vents, but this combination is the key to a durable and energy-efficient home. Here's why: in the winter, allowing a natural flow of outdoor air to ventilate the attic helps keep it cold, which reduces the potential for ice damming (snow that melts off a roof from an attic that is too warm and then re-freezes at the gutters, causing an ice dam that can damage the roof). Proper insulation and air sealing also keeps attics cold in winter by blocking the entry of heat and moist air from below. In the summer, natural air flow in a well-vented attic moves super-heated air out of the attic, protecting roof shingles and removing moisture. The insulation will resist heat transfer into the house. The most common mistake homeowners make when installing insulation is to block the flow of air at the eaves. NEVER COVER ATTIC SOFFIT VENTS WITH INSULATION — use rafter vents and soffit vents to maintain airflow.

Attic Fan Ventilation. Attic fans are intended to cool hot attics by drawing in cooler outside air from attic vents (soffit and gable) and pushing hot air to the outside. However, if your attic has blocked soffit vents and is not well-sealed from the rest of the house, attic fans will suck cool conditioned air up out of the house and into the attic. This will use more energy and make your air conditioner work harder, which will increase your summer utility bill. You don't want your unfinished attic cooled by your air conditioner. To prevent this, allow Hoffmann Brothers Heating and Air Conditioning to complete a home engineering analysis and thorough attic inspection to measure your home for the right size attic ventilator. Receive the peace of mind you deserve with a Hoffmann Brothers Heating and Air Conditioning attic ventilator.