Why energy Audit?
Why order an energy audit? As explained in Home Seals, an average home a can loose efficiency from countless areas of the home, wasting energy and money. And just like high miles can take their toll on your car, the age of your home is a determining factor in your homes inefficiency. An energy audit is the best place to start to discover the areas of your home that need the most attention and will produce the greatest energy savings.
What is Home Performance?
A home that performs well makes for a happier, stress-free you; putting more money in your pocket and less green house gases in the air. Your home’s performance can be characterized in different aspects including, comfort, energy efficiency, safety, and indoor air quality.
Over the years our understanding of home performance has evolved into an exact science of methods for improving efficiency. This science is used to correct energy losses in homes, making them cost effective, and cleaner, safer places to live.
So what is Home performance? Home Performance is a program sponsored by Energy Star and the US Dept of Energy. It is a comprehensive, whole-home check up buy an Energy Star certified contractor. The program is aimed at showing homeowners how to save money on their utility costs and increase their homes comfort, durability, and value through a process called “Energy Auditing.”
Improving home performance is best completed by using a whole home approach. The first step is a BPI certified energy audit. The auditing process works by analyzing the home and determining where failures and improvement opportunities exist. This is done by using building science techniques designed by Energy Star and the Building Performance Institute “BPI” to determine the most cost effective strategies to improving your home’s performance. Energy Audit testing reveals the homes weaknesses and strengths in efficiency, providing the homeowner a much better understanding of where their energy is begin lost.
What happens on the day of my audit?
During a Home Performance Energy Audit a Certified Building Performance Institute (BPI) certified professional will perform a series of tests to determine the most cost-effective approach to improving your home’s performance. The audit process ensures that the correct improvements are made specific to the conditions of your home.
Blower Door Test
A blower door is used to measure leaks in your home and to determine the air exchange rate between the interior and exterior spaces. It also determines where connectivity exists between the attic or crawl space and the condition space.
The blower door works by creating a negative pressure of 50 Pascal’s in the home. Next, by using a monometer, the auditor can measure the difference in pressure between indoor and outdoor air. Then through a series of calculations the home is given a CFM “Cubic Feet Per Minute” rating. The CFM rating is the measurement of outside air that is making it into the home, or the air leaks. This process can be duplicated on the homes HVAC ducting to measure leakage, as well as each individual room in the home to pinpoint energy losses and pressure differentials.
Some additional blower door tests include:
Pressure Pan testing identifies leaks in your air conditioning duct system by isolating the pressure in each individual air register.
A Static pressure test measures air flow and helps improper duct design.
Room Pressure Tests identify pressure imbalances in room that can contribute to hot spots in the home and extra workload on the homes HVAC system.
Thermal Imaging Cameras
Thermal imaging is known as Thermography which is a process that measures surface temperature by using infrared and still cameras. A thermal imaging camera works by sensing and displaying the heat spectrum in its pathway. It will effectively display hot and cold spots in the home so they can be addressed.
Importance of Thermography in the Audit
Thermal imaging gives the auditor the ability to view the thermal breaks in the home in a matter of seconds. The auditors can pass the camera across walls in the home; the resulting image will display a color spectrum ranging from blue to red, red being the hot zones. The resulting information allows the auditor to instantly identify red zones in the home as heat transfers. Auditors using thermographic measurements can then make recommendations for insulation improvements to the homeowners.
These improvements will stop air from convecting in the walls, which allows the heat to rapidly pass in or out of the home causing losses in energy and the hot zones indentified. Identifying these spots without thermal imaging is very difficult and nearly impossible because we cannot see into walls.
Thermal imaging For Insulation
Thermal imaging highlights problem areas, these problem areas often require very little work to correct. In the world of Home Performance a ¼” can be a mile, insulation that has settled over the year or fallen out of place away from the specified air barrier can contribute to rapid energy losses. Fro Example, an R-30 fiberglass batten insulation can degrade to as little as R-8 due to a ¼ gap between the air barrier. While this is an incredibly common occurrence, without thermal imaging these losses are often not identified and homeowners are left wasting energy.
Thermal Imaging for Attic Sealing
Just as thermal imaging can reveal lapses in insulation in walls and attic space, it can reveal leaks in the homes air barrier separating the living spaces from the attic. Thermography can detect even the littlest leaks in the ceiling; including can lights, Ceiling fans, light switches and even air registers. Every home has these leaks, and some more than others. By detecting them, the auditor can make recommendations on how to make the home more efficient.
Thermal imaging for Shade Screens
Another benefit of thermal imaging is its ability to identify temperature differences leading to Fenestration, which is the term used to describe heat gain or loss through doors and windows. Because homes are placed at different elevations in relation the sun, a home’s windows and door will have different exposures to solar radiant heat. Thermography will help identify which doors or windows will benefit the most from shading or solar screens. Cutting down solar heat from entering the home will always contribute to energy saving in the summer months.
HVAC Load Calculation and Inspections
After calculating the homes leakages and natural air flows in CFM, the energy auditor can inspect and assess your current HVAC (Heating and Cooling System) to determine if it is properly sized for your home. While an undersized unit may take too long to cool a home, a bigger culprit for energy loss and discomfort is an oversized unit. That is correct, a HVAC system that is too large for a home will not cool as efficiently as a properly sized unit. This is because a central air system must do two things to effectively cool a home.
Central air units must first it must remove the heat from the home and second, remove the humidity. When a central air unit is too large (too many tons, tonnage being the amount of air in CFM’s the unit is designed to deliver to the home) it will remove too much heat from the comfort zone too rapidly. This will cause the thermostat to turn the unit off before it has processed and removed humidity from enough of the homes internal air. This results in humidity issues in the home and discomfort.
A properly sized unit will both remove heat and humidity from the home because the unit runs long enough to recycle the perfect amount air before dropping the temperature to the desired setting. In addition, a central air unit uses the highest amount of energy when starting and gradually increases in efficiency as it continues to run. In other terms, a smaller unit will run longer but less often, while and oversized unit may turn on and off repeatedly, wasting energy.
Carbon Monoxide Level Testing
Carbon monoxide is the exhaust byproduct of a home’s gas appliances. These may include a range, dryer, water heater, and furnace. Carbon monoxide or CO is a colorless, odorless and tasteless which in certain quantities can be fatal to animals and humans. During the audit, the auditor will walk the home using a CO detector and inspect the homes level of CO in parts per million. Next a calculation is performed to determine if the home requires additional mechanical ventilation or if the home is at acceptable CO levels.
In addition, each combustion appliance is checked for appropriate CO levels to determine it’s burn efficiency. This procedure allows the audit to determine if the appliance is not only in compliance, but if it is consuming the proper amount of fuel and operating efficiently.
Gas Leaks check
In addition to CO testing, the auditor will perform a thorough gas leak check off all gas appliances and indoor supply lines. The purpose of this check is to determine if unwanted gas is entering the living space trough leaks in joints and fittings. In many cases small gas leaks are detected along junctions where joints have become loose over time. The gas leaking into the home from these tiny leaks is wasteful and dangerous, so it is necessary to identify them as soon as possible.
Gas checks are performed with a gas sniffer, which is an ultrasonic tool designed to identify small traces of gas with an audible alarm. For safety and compliance reasons, once a leak is found the auditor must stop work immediately until the leak is corrected.
Is My Home Efficient?
While there is no way of knowing your homes efficiency level without a certified energy audit, chances are, your home needs attention. In fact, Energy Star estimated over 92% of homes have in-efficiencies needing attention. This is due to several unfortunate truths. First, homes are rarely designed around efficiency; energy efficiency is typically an afterthought at best. Second, homebuilders very seldom go the extra mile in energy efficiency, and in some cases fail to finish the first mile needed for true efficiency. So, the long answer is no, your home is not as efficient as it could be. That being said, the improvements are rarely as expensive as homeowner fears and the payback in savings is tremendous.
Weatherization or a “Home Seal” is the process of improving the “envelope” of a home. Weatherization helps to better insulate and seal the home, effectively blocking the outside elements and helping to maintain a interior climate. Weatherization includes several key parts.
Benefits. According to Energystar.gov, 92% of homes have leaking or blocked ducts accounting for up to 20% loss in efficiency. Leaking ducts can also bring in dust and carbon monoxide form the attic, causing interior air pollution to be 2-5 times greater than outside air. A properly sealed duct system can eliminate up to 15% of your annual energy costs and will significantly reduce the workload of your heating and cooling system, prolonging its lifespan.
Environmentally and wallet friendly
Installation time : 1-2hrs