2018 NC Energy Conservation Code calls for 5 CFM per 100 square feet of conditioned floor area (or 5 per cent) of total duct leakage for all newly installed residential duct systems. Green Door Energy has tested many thousands of duct systems in NC's Piedmont Triad area for dozens of HVAC contractors and can advise new or less-experienced contractors on common duct leakage points and pitfalls to meeting the 5 per cent maximum leakage rate. Moreover, we will never leave the jobsite without trouble-shooting the duct system in the event of a reading that does not meet the code mandate. Indeed, it is our duty (and our pleasure) to advise and assist the contractor in pin-pointing leakage paths. We can perform smoke testing to help locate leaks, and in a pinch, we can even help you seal duct leakage with bucket mastic, the tried-and-true method of properly sealing ductwork (contact us for specific details on this somewhat outside-the-box service). If a portion of the duct system is located between floors in a two-story home, or in a sealed crawlspace or full- or partially-finished basement, and if the home is an existing home or a new construction home at the post-construction phase, you may be able to use the alternative path of meeting code for duct leakage: 2018 NC Energy Conservation Code allows for 4 CFM per 100 square feet of conditioned floor area (or 4 per cent) of duct leakage the outdoors as a viable means of demonstrating code compliance. A duct leakage to the outdoor test is performed with the duct testing fan and the whole-house air leakage (a.k.a., blower door) fan running simultaneously. With the duct system depressurized to -25 Pascals, and the house depressurized to -25 Pascals, the measured leakage has only one path: outside the thermal envelope (or the conditioned space). For duct systems with substantial areas located in conditioned or semi-conditioned spaces, Green Door Energy has observed that meeting the 4 per cent mark for duct leakage to the outdoors is very attainable.

Are you tired of getting insufficient time on the jobsite from larger companies, or receiving a call or an email simply stating that you did not pass the duct leakage test? If so, Green Door Energy's dedication to customer service will provide you with a breath of fresh air (pun intended) as we serve you in meeting NC Energy Code requirements. Please contact us to get started; we'd be happy to help!

HVAC system sizing is vitally important to a home's performance, durability, and efficiency, as well as to the health of its occupants. Gone are the days of "rules of thumb" system sizing, where many contractors installed air conditioners with cooling capacities of one ton for every 600 square feet of floor area (or even 500 or 400 square feet). More stringent energy codes require the HVAC contractor to work smarter to abide by ACCA's Manual J with advanced software applications such as Elite Software's Rhvac or Wrightsoft's Right-Suite Universal. Are you too busy out in the field or running a crew to perform a Manual J? Is that "one of these days" you've mentioned regarding training for the use of software for load calculations failing to materialize? Let Green Door Energy help! We've performed hundreds of ACCA Manual J load calculations using Wrightsoft Right-Suite Universal for homes ranging in size from 300 square feet right on up to 14,000 square feet. Please contact us to get started. We're here to assist you!

As one of North Carolina's first Home Energy Rating companies accredited for the ANSI RESNET/ACCA/ICC Standard 310 HVAC Grading system, Green Door Energy can help HVAC contractors hoping to work on an ENERGY STAR New Homes project, but who yet do not have accreditation through an H-QUITO (HVAC Quality Installation Training and Oversight Organization) such as ACCA or Advanced Energy. If you have a home builder client who has been asked to construct an ENERGY STAR-certified new home, but you are unsure of the return on your investment in accreditation for ENERGY STAR New Home HVAC installations, contact us to discuss how we can help.

You've performed an accurate Manual J load calculation, you've installed the duct system, and you have performed (or have subcontracted with a qualified individual or organization such as Green Door Energy to perform) a duct leakage test. Aside from the usual startup procedures, there is one task which is often overlooked: balancing air flows at supplies and returns. Properly balanced air flows that are within 10 per cent of the design air flow from the load calculation will lead to a more efficient system, increased homeowner comfort, happier builder clients, and fewer callbacks. Green Door Energy owns and utilizes an ACIN FlowFinder Mk II, Europe's gold standard in air flow measurement, and has performed balancing services at both homes and at light commercial buildings. Please contact us for more information.