BLOWER DOOR TESTING:
A carpenter would not build a home without a measuring tape. likewise a blower door test, is the measuring tape of the energy specialists. the result is accurate and specific information that relates to the comfort level and energy loss of the home.
The blower door is a large calibrated fan that is temporarily mounted in a home’s outside door to measure the ” leakiness” of the house and to assist in finding the location of the leaks.
At PEC we know blower door results are very important to find out before considering spending money to improve the comfort and economy of a home. For example: Many people assume if their house is uncomfortable that windows are the issue. Windows whether older or new have one common weakness, glass. Glass has a low R-value, and even the most top of the line glazing’s are 20 degrees colder than wall surfaces in the home on a 20 degree day. Most of the time, good window coverings, like interior shutters, are a much better investment and comfort improvement than new windows.
Another prime example: People tend to assume if their house is uncomfortable, that the furnace or air conditioner is the problem and in many cases replace their systems unnecessarily. In some cases heating and cooling efficiency can be greatly improved by simply air sealing the home and duct systems at critical leakage points. This allows the current systems to heat and cool the home instead of the outdoors. Also the ducts or air distribution systems leak unless the ducts are sealed, which is seldom the case. These leaks cause pressure differences between different zones in the home. This causes unconditioned air to be drawn into the home or conditioned air to be forced out.
Many times customers call us after putting in new windows and or furnaces , because their comfort or energy issues have not been significantly improved.
These examples and many other things becomes apparent when observing the homes surfaces temperatures using a thermal camera during an energy assessment.
When using a blower door in conjunction with a thermal camera, duct pressure diagnostic tests and common sense evaluations, our auditor provides homeowners with a practical list of energy and money saving steps, and explains how and why your house is costing you money. Then a prioritized estimate is proposed showing the method , steps, and cost required to take corrective actions.
A typical audit is comprised of several steps:
1) A thorough visual inspection of the home’s building envelope.
2) An insulation check, generally involving infrared thermography, to pinpoint spots where insulation may have settled, been improperly installed, or where it may be missing altogether.
3) An air leakage test using a blower door, to measure the cumulative effect of all the air leaks in the home.
4) A ventilation check: healthy houses have appropriate ventilation, and an auditor will test ventilation systems to ensure that they conform to safety standards.
5) All visible gas lines, the gas stove, and gas powered water heater will be examined to insure that there are no leaks.
6) The auditor will evaluate if your central heating system is causing pressure differences, or is out of balance. When HVAC systems leak, which is always, the system can force air out or pull air into the home along with other pollutants.