So, what it is Blower Door Testing? Blower door testing is a quality assurance tool for determining if MEP systems and a building can provide the requirements it was designed for. Blower Door Testing is as simple as this: am I throwing money out the door, or window? Imagine your house’s HVAC system, and it is either heating or cooling, and having your windows open. It literally means you’re throwing away money by having the HVAC system run while the windows are open. This in turn causes the HVAC system to run more frequently to stay at the same desired (set) temperature. The same goes for any type of building structure. To conserve energy while HVAC systems are running, you must shut your windows, right? In a building there are many different places that air can leak into or out of ; stopping air leakage by sealing it airtight conserves energy. Having an airtight building can also prevent moisture from entering the building through vapor transmission and while helping to keep out pollutants in the building.
A Blower Door Test pressurizes the building to simulate different conditions and to find air leaks. The equipment consists of a high-powered fan that blows air into or exhaust air out of the building. The speed of the fan increases or decreases internal building pressure and allows air to move through pathways such as cracks or openings of the building that otherwise may not be found. This allows a measurement to be taken of how much air is being cycled into or out of a building through the fan. Using the resulting pressure measurements and the amount of air moving through the fan into the building allows for calculations to be made to determine the amount of air leaking out of the building. The amount of air leakage is then compared to historical data to determine its effect on energy consumption. How do we determine where the building is leaking air? There are several methods used in determining leak locations. Standard methods include infrared thermography (camera able to see surface temperature differences and display it as a picture), smoke pencils/pens, or theatrical fog. These methods each require knowledge of building construction and science to appropriately analyze and determine leak sources.
These are some reasons for establishing the proper building tightness:
- Reducing energy consumption due to air leakage
- Avoiding moisture condensation problems
- Avoiding uncomfortable drafts caused by cold air leaking in from the outdoors
- Determining how much mechanical ventilation might be needed to provide acceptable indoor air quality.
How big of a building can BEPG test for air leakage? BEPG has three (3) fans which can produce approximately 3,500 to 4,000 cfm. The International Energy Conservation Code (IECC) defines the amount of Air Changes Per Hour (ACH) allowed at a specified pressure. Depending on the test pressures required to achieve building-code required air-tightness, BEPG with can test up to approximately 200,000 ft3 buildings. We also have access to additional equipment and techniques for larger buildings if necessary. Contact us for specific details on air leakage testing of whole buildings using blower doors.