Ventilation & Air Quality
In this “Keeping It Cool” episode of Blueprint for Home Building, you’ve learned about the basics of air conditioning, the importance of the size of your HVAC system and how zoning your system can be energy efficient and less costly. In this final segment it’s time to discuss the air quality of your new house.
Remember, the “V” in HVAC stands for ventilation.
Find out why the “V” in HVAC — ventilation — is so important to your home’s air conditioning system .
How Does Ventilation Affect Your Air Conditioning System?
Ventilation refers to the movement and exchange of air in the home, as performed by your air conditioning system. Proper ventilation is important because it will keep fresh air moving inside your house while removing bad or stale air to the outside.
If you have a tighter house, a newer one, then outside ventilation is very important,” Gary Ostler (President of Four Seasons & A.C., Inc.) said. “The air gets stale. You will be building up carbon monoxide inside and mold can form, and just the general freshness of the whole environment is improved if you can bring in some outside air.”
Fig-A
Any air conditioning system your HVAC contractor installs will have a series of vents (figure A). Some of these vents will pump in outside air, and other vents will draw air that has been inside your home long enough to become stale. Vents that draw out this stale air are called “return air vents.”
The goal is to take bad air out and put good air in, which is extremely straightforward and simple!
Figure -B
Note: The American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) says that you should change the air about three times an hour essentially in order to have the adequate amount of quality air in the home. A quality air conditioning system that is installed well will have the proper series of return vents (figure B) that can change your air on a regular basis.
Air Pressure Test
Fig-C
One of the rules of thumb for ventilation is that one cubic foot of air moving out of the house should have one cubic foot of air moving into the house. One of the best ways to determine the level of ventilation in your home is to have an “air pressure test” (figure C) performed. Ask your builder or local HVAC engineer about having a pressure test done on your home
Construction Tip: One of the most common ways to add quality ventilation is to have a bathroom fan that is efficient at moving air in and out of your home.
From: “Blueprint for Home Building”