Posted: September 13, 2019||
Author: Sam Myers
Within the confines of the HVAC field, airflow behavior is one aspect that can be difficult to understand when it comes to proper duct system design and airflow measurement. The challenge of providing a visual display of an issue that is invisible to the naked eye is a regularity we face when working with clients, apprentices and students. Once a duct system is installed, we can use diagnostic tools such as flow hoods and duct testers to measure and expose air flow and leakage, then record our reading. We can also use thermal imagi
Starting in September of 2019, a duct leakage test will be required for all residential new construction homes that have ductwork outside of the conditioned space. This includes ducts located in vented crawlspaces, ventilated attics, and attached storage rooms that are not conditioned.
In many states, a certification of some type is typically required. However, in Virginia’s case, the tester’s ability to operate the equipment is to be determined by the AHJ (Authority Having Jurisdiction).
Luckily, Retrotec’s DucTester systems come with an online training module that provides the user with a Manufacturer’s Certification. This can be presented to building inspectors to provide proof that the tester is knowledgeable when it comes to testing ducts for leakage. This is unique only to the Retrotec brand of testing equipment.
A recent Retrotec webinar, “Duct Testing Best Practices,” walks through duct testin
This is the 3rd installment of a monthly column from Ben Walker, Co-CEO of Retrotec. Ben's column focuses on observations on the art and science of high-performance building and home testing.
As many as 30 million U.S. homes may have loose-fill attic insulation made from asbestos-contaminated Zonolite. Here's how to determine if a home has it and what to do if it does.
This is the 2nd installment of a monthly column from Ben Walker, Co-CEO of Retrotec. Ben's column focuses on observations on the art and science of high-performance building and home testing.
A blower door test, along with before and after load calculations of a leaky 1915 home, show the value of these technologies for remodelers and homeowners.
A lot has been written about making new homes energy efficient, comfortable and healthy. That's important, but as more communities with high-performance new homes become available, more owners of existing homes want the same benefits.
Just tightening up a home isn't enough, however. Homeowners want you t
Authored By: Sam Myers
Testing ductwork in residential HVAC systems for air tightness is essential to ensure a home will be energy efficient and comfortable. Tighter ducts help homes perform better by allowing conditioned air to travel to its intended destination. They also keep newly conditioned air from escaping to the outside of the home. More states and municipal code jurisdictions are including duct sealing and testing requirements in their energy codes for residential new construction. It is also a part of the RESNET HERS Rating process as well as a function of BPI Analysts when they perform energy audits. There are two methods used for testing ducts: Total duct leakage and leakage to outside (LTO). It is best to verify with local code requirements to see which method is specified. Some state a
Posted: September 26, 2018||
By: Sam Myers, Retrotec and Kristi Brodd, Advanced Energy
Hurricane Florence brought record amounts of rainfall and devastating flooding across North Carolina, especially in the eastern part of the state. According to CNN measurements, some cities saw close to 3 feet of rain over four days, which is the highest rainfall total for any tropical system to hit the East Coast of the United States.
As flooding recedes, many people are returning to their homes and beginning the restoration process. If you are moving back into a home that was flooded, it is extremely important to become knowledgeable on moisture management and take the necessary steps to keep your house safe and healthy for you and your family. Just because the water is gone and your house looks back to normal, does not mean that there is no damage or dangerous mold behind the walls, floors and ceiling.
Many families suffered the effects of mold after flooding caused by Hurricane Floyd in 1999
Whether it’s for a building code, third-party home performance program, HERS rating or quality control, testing ducts on new construction homes before the drywall is installed is a good idea to easily fix issues. Once the drywall is installed, it can be difficult to access certain parts of the duct system that need air sealing, especially if there are ducts in chases or between floors. Sometimes it can be tricky to set up your duct tester at rough-in since you typically don’t have a grille to tape the flange to, especially if the return is in the ceiling. Unfortunately, duct mask doesn’t stick to wood and mastic ver
A comprehensive guide to getting the most out of your blower door system
Authored By: Sam Myers
A blower door system can do much more than tell you how much your building is leaking. It can also help you determine the location and severity of the leaks in different zones. There are also cases where you can use your blower door to determine if some ventilation systems are working properly. Knowing the tightness of a home and finding leaks is helpful to HERS Raters, BPI analysts, insulators and HVAC contractors. In this article we’ll introduce the blower door system and ho
When it comes to home energy performance, comfort, durability and health, the United States falls short in the ranks compared to other developed countries. This is based on the 35 years of experience that Colin Genge has in testing houses from coast to coast and from selling diagnostic tools to over 10,000 technicians who have tested millions more.
Duct leakage in existing homes can range from 12% to 35%.
Most American houses have poor quality flex duct running outside of the envelope into attics and/or crawlspaces and typically leak an average of about 20%. Some as high as 50%! Code for new
As you may have heard, the RESNET 380 standard will replace RESNET Ch. 8 which dictates how raters test homes for envelope leakage, duct leakage, mechanical ventilation, and duct system air flows. Any home permitted on or after July, 1 2018 must be tested in accordance to the 380 Standard. The standard currently applies to all single-family homes as well as multifamily projects that are three stories or less. There are more updates coming for multifamily so make sure you are signed up to receive email updates from RESNET.
One goal of the 380 standard is to improve consistency throughout the HERS process and to reduce the need for Raters to make judgement calls when taking measurements in the field. To help achieve this, the standard includes definitions for:
- Conditioned Space Volume
- Unconditioned Space Volume