Audit Details

Below are several examples of home performance issues your Auditor will investigate and test during your Compreshensive Home Energy & Health Audit. 

 

The shell or “building envelope” of a home is designed to protect occupants from outdoor elements. Unfortunately, most existing and older homes have building envelope air leakage, known as infiltration, through windows, doors, walls, floors and ceilings, as well as attics and crawl spaces. This leakage allows air, moisture and outdoor pollutants to penetrate indoors making the home uncomfortable and causing high energy bills. Studies show that 35 to 40% of heating and cooling costs pay for infiltration alone.  Air can escape through many obvious and not-so-obvious cracks and gaps around your home making your house feel uncomfortable and your energy bills costly.  Your Auditor will use a Blower Door to measure the amount of air infiltration and identify critical leaks.

 

 

Duct Leakage
Leaky ducts are a leading cause of poor indoor air quality as pollutants are drawn into the system, re-circulated and distributed throughout the home through the heating and cooling systems.  Leaky ducts also contribute significantly to a home’s energy loss. Homeowners lose 20% to 45% of heating and cooling energy through leaky and poorly insulated ducts. HVAC systems leak at the air handler and plenum seams, trunk lines and at the duct-to-vent joints.

 

Duct Design & Installation
Heating & Cooling accounts for approximately 45% of your total home energy use.  So when your system isn't working properly it's time to replace your equipment - right?  Not necessarily - and probably not yet.  Surprisingly, 50% of heating & cooling system energy loss is from your ducts!  

Equipment Sizing & Performance Efficiency
The national average of HVAC system performance is 60%.  This means that if your existing, or even new, system is not properly sized, charged, tuned/commissioned or has an improperly designed duct system, you are receiving approximately 60% of what you paid for.  Proper Duct Renovation is typically a better option than replacing equipment.  A well-sealed building with properly sized and installed duct work may qualify for a smaller, less expensive unit when it is time to replace your equipment.  Your Auditor will provide performance testing on your HVAC system.
 
Ventilation & Fresh Air
Most heating and cooling system simply recirculate interior stale polluted air instead of introducing fresh air into your home.  Interior air pollution can be 5-30% more polluted than outside air.

 

Water Heating & Usage

 

Water heating accounts for 15%-20% of your total home energy use.  Ensuring a well maintained, insulated, properly set and energy efficient water heater is critical to creating an energy efficient home.  The easiest and most cost-effective mechanical way to decrease your family’s water consumption is to install low-flow shower heads and faucets throughout your home.  Your Auditor will measure water flow from your showers.

 

 

 

Insulation is only effective if it is a continuous thermal barrier, with no air gaps or voids, and is in continuous contact with the air barrier or building envelope. Wall insulation, to have the maximum effect, must be encapsulated on all six sides by air barrier backing, such as a stud cavity. One reason why bonus rooms are so notoriously hot and cold is because there is no backing on the attic side of the insulation batts in the kneewalls.
 
Batt insulation is very often improperly installed, stuffed into stud cavities, with gaps and voids between the batt and the drywall. When insulation is compressed, it loses R value. Batts are often stuffed in front of or behind piping and wiring in stud cavities, compressing the insulation and leaving an air gap.  Your Auditor will be utilizing a Thermal Imaging Camera to help identify of missing or improperly installed insulation.
 

 

Attic
An effective thermal barrier can prevent humid outside air infiltration. If there are flaws in that barrier, breaks and leaks, this moist air can be drawn into the conditioned space. Negative pressures from an imbalanced ventilation system can accelerate this infiltration. Introduced water vapor will condense on any surface below dew point, such as cold spots, caused by breaks in the insulation. Moisture build up like this will breed mold and mildew. During the winter months, if warm air leaks from the home, it will condense on the cool attic sheathing and create an environment for mold.
    
Crawl Space
Crawl space vents are supposed to keep the space ventilated and dry, but in our mixed-humid climate, they work the opposite. Humid air from the outside is drawn in and condenses on cool surfaces that are below the dew point (floor joists and rimbands, etc). This moisture promotes mold growth. If there are leaks in the crawlspace return ducts, mold spores can be drawn into the ventilation system. If that system is not pressure balanced, negative pressures in the main return area can pull moldy, crawlspace air into the living space through air leaks in the framed floor.   
   
A majority of the air you breathe in your home comes up from your crawl space.  The average temperature of a typical vented crawl space in the Southeast region of the U.S. is perfect for breeding moisture and mold which can create a musty smell and release toxins that can affect your family's health.  Sealing your crawl space keeps mold away with a high quality moisture barrier and converts it into a semi-conditioned dry space.
     
Closed crawl spaces have been proven to save homeowners money on their energy bill.  By encapsulating your crawl space and converting the area into a "controlled" air space, you will lessen the impact it has on the indoor temperature of your home which will lower your energy costs and help create a more comfortable living area.

 

Room Imbalances

Pressure and Indoor Drafts
Bedrooms and bathrooms usually have a forced air supply but no return path except through an open door. If bedroom and bathroom doors are shut, pressures build causing low pressures in the main central area. These negative pressures in the central area can multiply and create a vacuum effect which pulls outdoor air through the adjacent building shell, from the garage, attic, crawl space, and around windows and doors. In the winter this would be cold and drafty air, in summer, hot and humid air.

Temperature
Hot and cold spots in walls, ceilings, and floors radiate uncomfortable temperatures. They are caused by improper framing-breaks in the air barrier, missing or improperly installed insulation.

 

 

 

Combustion appliances need fuel and air to burn and operate properly. Room pressure imbalances in a house can quickly result in the back drafting of an open combustion gas water heater or furnace and lead to dangerous consequences.  Your Auditor will check for worst case scenario of negative pressure in all rooms containing open combustion burning appliances.

 

Carbon Monoxide Levels

 

Carbon monoxide (CO) is a natural byproduct of the combustion fuel process. It’s important that CO levels be controlled and appliances properly vented to ensure the safety and well-being of your family.  Your Auditor will test CO levels at all gas appliances and check for gas leaks near the units.

 

 

Indoor Air Pollutants

 

Toxins are commonly found in our home environment in the form of mold, pollen, carbon monoxide, pesticides, chemicals and fertilizers.  After eliminating direct sources of pollutants, controlling moisture and room pressures inside homes are the keys to improving indoor air quality (IAQ) levels and your family’s health.


Rainwater Management

 

Rainwater drainage can rot roof sections where rooflines join at right angles if they are not properly flashed. Grading must divert stormwater away from house foundation. Foundation drains should be installed (separately from gutter drain lines) around the perimeter of the house to move groundwater away from the foundation.