The term “air tightness” refers to the control of airlfow in a home, or the rate at which air leaks from the home. When a home is leaky, air penetrates and exits the home wherever there are cracks, gaps and holes present. This loss of conditioned air (both Heat and AC) causes your utility bills to be higher all year, or put another way – your hard earned dollars leaking out of the home! The uncontrolled loss of air between the inside and outside of your home can be responsible for up to 50% of the home’s energy loss. By reducing air leakage your utility bills will be lower, your dollars stay in your pocket (not Xcel’s!) and most importantly, your home will be more comfortable.
Good question – and one we get asked often!
You’ve probably heard the expression, “Build Tight, Ventilate Right.” A home cannot be too airtight – provided it has a reliable source of fresh air. For every cubic foot of air that leaks from the home, a new cubic foot of air is re-introduced into the home. Fresh air can be introduced into a home through various means – infiltration, natural ventilation and mechanical ventilation. Infiltration is air that exits and enters the home uncontrolled through gaps, cracks and holes.
Natural ventilation is air entering the building by means of open windows and doors. However, the most ideal form of fresh air is introduced by mechanical ventilation which is air that is controlled in the home by fans. For instance, kitchen and bath fans are types of mechanical ventilation which help remove odors and moisture while helping replace the air inside the home with fresh air. A more permanent form of mechanical ventilation can be performed by adding systems to the current HVAC appliances that move fresh air throughout the house using the ducted system to disburse fresh air.
The rate at which indoor air is replaced by outdoor air is measured as the “air exchange rate” or “air changes per hour”(or ACH). The Association of Air Conditioning and Refrigeration (ASHRAE) recommends that average sized homes receive .35 air changes per hour – or that ALL the air inside an average home be replaced with fresh air at a minimum every 3 hours. Using calibrated testing equipment (ie blower door and infrared diagnostics) a certified AirTight Energy auditor can locate specific air leakage sites in your Denver home and determine how leaky or airtight a home is. Based on the data from the tests, a series of improvements are recommended to address the leakage and air exchange rate for a healthy home.
Why is it important to have fresh air circulated throughout a home?
The US Environmental Protection Agency (EPA) ranks poor indoor air quality among the top five environmental risks to public health. Air inside a home can become stale, contaminated and even hazardous to your health. Heating and AC appliances typically burn gas to produce energy and in the process give off Carbon Monoxide. Extended exposure to Carbon Monoxide can be deadly. In addition to Carbon Monoxide, many volatile compounds are released by paints, carpets, and cleaning supplies that can have serious health consequences for the inhabitants of a home. Replacing stale, possibly contaminated air with fresh air becomes essential for maintaining a healthy home
Using the blower door in combination with the infrared camera, an auditor can pinpoint the worst leaks during a Denver energy audit. Sometimes the best solution for that leak is a simple as applying caulk. Other times recommendations may include: adding more insulation to an attic or crawl space, blowing cellulose into existing walls, replacing lightbulbs, replacing outdated appliances and replacing or weatherizing drafty doors and windows.Every Denver home is unique and every home will have different requirements to make the home as energy efficient and comfortable as possible. Denver energy audits can be performed on new and old homes – virtually every home has leaks!
Audits can take approximately two to three hours to complete – depending upon the size and complexity of the home.
Three critical tests that are NOT performed by an AirTight Energy auditor are the presence of Radon, Mold and Asbestos in a home. If you have concerns about any of these potential health hazards, contact a professional remediation company who specializes in these types of tests. (AirTight Energy can provide the names of several contractors upon request.) If you know you have Asbestos or mold present in your home, often times you can still perform an energy audit. Be sure to alert the auditor to their presence so they can take special precautions prior to running all the diagnostic equipment.
** AirTight Energy serves the entire Denver Metro area. Call us today to schedule your Denver energy audit and start saving $$ and improving the comfort of your home! 303-638-3172 **