Indoor Air-Quality and Fresh Air Ventilation
Al’s Plumbing, Heating and Air Conditioning sells various Whole-House Air Filtration Systems. We also sell Heat-Recovery Ventilators (HRV) which bring fresh air in while exhausting indoor air after most of the heat is removed from it.
1. Do you have unhealthy Indoor air Quality (IAQ)? 2. What caused it? 3 What is needed to correct it?
Occupants report one or more of the following Heath Issues in homes with poor Indoor Air Quality:
- Dryness and irritation of the eyes, nose, throat, and skin
- Shortness of breath
- Hypersensitivity and allergies
- Sinus congestion
- Coughing and sneezing
Signs your home which may indicate poor Indoor Air Quality:
- Mold growth
- Unpleasant Smell — mold smells musty. VOC’s can have a sharp smell (oven cleaners are great examples of a sharp smell)
- Humidity — Recommended humidity is 30-50%. Houses in colder climates may record lower levels of humidity during winter. Homes in warm climates may experience higher levels in the summer.
When we talk about indoor air quality, we are referring to various pollutants such as:
- Household chemicals such as solvents, paints, and aerosols.
- Combustion by-products from fuel-burning (not electric) unvented sources in the home. One of the most common is are gas cooking appliances.
- Carbon Monoxide
- Breathable particles generated by open fireplaces.
- Tobacco smoke
- Mold or mildew
- Dust mites
- Pet dander
- Solvents, aerosols, cleaning and home-fragrance products
* SOURCE: http://www.consumerreports.org/cro/magazine/2012/06/is-poor-indoor-air-quality-making-you-sick/index.htm
3 Steps to Better Indoor Air Quality
1: Increase ventilation. We keep our windows tightly shut in the winter, and flinging open a window is not the answer. Outdoor air contains by-products of gas emissions from cars and trucks, industrial pollution, as well as dirt and mold. The highest quality ventilation solution is a Heat-Recovery Ventilator (HRV) which filters incoming outside air, mixes it with heated (or cooled) air and disperses it through the furnace.
NOTE: HRV are an excellent way to improve Indoor Air-Quality in newer homes, especially Energy Star rated homes. Older homes (built before 1980) likely leak enough air (through air-infiltration) to keep the Indoor Air-Quality adequately high.
2: Turn on the AC. Many pollutants are water-soluble, and since air conditioners remove water from the air, they help remove these pollutants, according to WebMD.
What is Air Infiltration and how does it affect indoor air quality?
Every home must “breathe” in order to maintain indoor air-quality. You may feel some air seeping into your home around windows, doors, skylights, electrical outlets, walls, floors or the roof. This is air infiltration and every home has some air infiltration. Air Infiltration creates air changes (outside air replacing inside air).
Home built in 1980 had an average of up to 15 Air Changes per Hour (ACH). *
In a newly built home, the maximum allowed Air Changes per Hour is up to 5 (in DFW).
An Energy Star Certified home, the maximum allowed Air Changes per Hour is up to 3 ACH (in DFW).
* SOURCE: http://www.greenbuildingadvisor.com/blogs/dept/musings/revisiting-energy-saving-handbook-1979
While most older homes leak enough air to satisfy their air-quality needs. Newer homes are built to high energy-savings standards, and some do not leak enough air. These homes must have a ventilating device to ensure indoor air quality.
A common device for this ventilation is a Heat Recovery Ventilator (HRV) which recovers 60% – 80% of the heated (or cooled) temperature from the outgoing air. It uses that recovered heat / cooled temperature to heat or cool incoming fresh air before it enters the home.
This diagram shows how the HRV works: 1. Removes stale air 2. Removes most of the heat or cool temperature from the stale air 3. Uses that recovered heat / cool temperature to bring the outdoor air temp close to the indoor air temp. 4. Sends the fresh air into the home.
Al’s Plumbing, Heating and Air Conditioning sells and installs Heat Recovery Ventilators(HRV). Call for an appointment today to discuss having an HRV installed to increase the ventilation and improve indoor air quality in your home.
Air Infiltration Testing
You can have any home tested to determine how much air infiltration is occurring. The most common way is the “blower door test”.
The technician seals off an open door with a temporary vinyl seal which has a blower in the bottom. The blower is powered through a system which increases the outward air-flow as required. The purpose of this test is to create negative pressure inside the house which will then identify everywhere the house leaks air. Once identified, many of these leaks can be sealed.
Some things cannot be corrected, as the design of the building component must allow air to infiltrate. This is common of windows which slide up & down or sideways. To make them as air tight as possible, they would become very difficult to open and close. The design of the window requires a balance of air infiltration with ease of operation.