Frequently Asked Questions

How do you test a blower door?

A blower door is a diagnostic tool to determine a building’s airtightness. By measuring the extent to which air can flow into and out of a building, the blower door makes it possible to quantify a building’s airtightness. The test is performed by hanging the blower door frame in a doorway and attaching the door panel to the frame. Once the door panel is sealed, the blower door fan is turned on, and the pressure within the building is monitored. The extent to which air can flow into or out of the building is then calculated based on the change in pressure. Blower doors are essential for diagnosing building tightness and ensuring that homes and other structures are adequately sealed.

The test provides valuable information about the building envelope’s ability to resist air leakage, which can lead to energy loss, drafts, and other problems. In addition, the results of the test can be used to determine where air sealing and/or insulation improvements are needed.
While a blower door test is not required by code, it is highly recommended for new construction and major renovations. The test cost is typically around $300-500, but can vary depending on the size and complexity of the building.

A blower door test is a diagnostic tool used to assess the airtightness of a building envelope. The test involves mounting an airtight frame with a calibrated fan in an exterior door opening. The fan is used to pressurize or depressurize the interior of the building, and the resulting air movement is measured to determine the airtightness of the building envelope. The test is repeated at different pressures to ensure accuracy.

A blower door test typically takes 30 minutes to one hour to complete. The time required can vary depending on the size and type of home, as well as amount of required observation by the technician performing the test. However, most homeowners can expect the entire process to take no longer than 2 hours.

The answer is yes. You can be inside the house during a blower door test. The test involves sealing all doors and windows, then running a large fan in the front door. This depressurizes the house, which makes it easier to find air leaks. Individuals can walk around the home and feel for where the air leakage is coming from.

This depends on how well your home is insulated and air sealed. If your home is not well insulated or has a lot of leaks, it can be quite difficult to pass a blower door test. However, if your home is well insulated and airtight, it should be relatively easy to pass a blower door test. Either way, it is always a good idea to consult with a professional energy auditor before attempting to perform a blower door test.

It depends on what climate zone the dwelling is located in to meet code compliance. If in climate zone 0-2, the required result is 5.0 ACH (air changes per hour). If in climate zone 3-8, the necessary result is 3.0 ACH. Please check in with our energy team to learn about which climate zone your project is in.

Yes, energy audits are definitely worth it! Here are three reasons why:

1. Energy audits can help you save money on your energy bills.

2. Energy audits can help you find ways to reduce your carbon footprint.

3. Energy audits can help you improve the overall efficiency of your home or business.

1. Whole-house/building energy audits

2. Systems energy audits

3. Equipment energy audits

An energy audit is an inspection, survey, and analysis of energy flows to reduce energy costs and consumption. It covers all forms of energy used in a facility, such as electricity, natural gas, oil, water, and solar.

The auditor will first assess the energy usage of the facility to identify where there are opportunities for energy efficiency improvements. They will then recommend measures to reduce energy consumption and costs. These measures may include installing more efficient lighting, heating, and cooling systems, or improving the insulation of the building.

An Energy Audit will test the energy efficiency of your home, and make recommendations for improvements. The auditor will look at your home’s:

-Heating and cooling systems

-Insulation

-Windows and doors

-Ventilation

-Appliances

-Lighting

-Water heating

-Other factors that affect energy use

The answer to this question depends on several factors, including the climate, the type of insulation, and the purpose of the ductwork. IECC required that a duct system should not have more than 4% leakage.

Duct leakage testing is performed to measure the airtightness of HVAC ductwork. This type of testing is important because leaks in the ductwork can lead to decreased efficiency of the HVAC system, as well as increased energy costs.

To perform a duct leakage test, a fan is used to pressurize the ductwork and a calibrated manometer is used to measure the pressure differential across the ductwork. The test is typically conducted at two different pressures, typically -0.1 and -0.4 inches w.c. (water column).

The results of the duct leakage test are reported as a CFM (cubic feet per minute). 4% duct leakage per 1,000 sq feet result is what would pass IECC code.

To check for duct leaks, you will need to do a few things. First, you will need to make sure that all of the registers in your home are clean and unobstructed. Next, you will need to inspect all of the ductwork in your home for any signs of damage or leaks. Finally, you will need to test the ductwork for air tightness.

If you find any leaks in your ductwork, you will need to repair them as soon as possible. Leaks in your ductwork can lead to a loss of heating and cooling efficiency, and can also lead to higher energy bills.

If you have a leaky duct, the best way to fix it is to seal the leaks with mastic or metal tape. You can also use a sealant that is compatible with your duct material. Once you have sealed the leaks, make sure that the area around the duct is well-ventilated so that the mastic or tape can dry properly. Consult with our team at LSEE and we will help determine if the leak is repairable.

Most products that have earned the ENERGY STAR label are certified for a period of two years. Some product categories have different certification periods. For example, computers and monitors must be recertified every three years to maintain their ENERGY STAR status.

To earn the ENERGY STAR label, a building must perform in the top 25 percent of similar buildings nationwide for energy efficiency and meet strict energy efficiency performance standards set by the U.S. Environmental Protection Agency (EPA). ENERGY STAR certified buildings use an average of 35 percent less energy than typical buildings and generate 35 percent fewer greenhouse gas emissions.

To be ENERGY STAR qualified means that a product meets or exceeds the energy efficiency guidelines set forth by the Environmental Protection Agency (EPA). Products that are ENERGY STAR qualified use less energy, which can save you money on your energy bill and help reduce your impact on the environment.

What does a HERS rater do?

HERS raters are certified professionals who conduct on-site evaluations of homes to assess their energy efficiency. The goal of a HERS rating is to provide builders with an accurate estimate of a home’s energy performance, as well as recommendations for improving the home’s energy efficiency.

HERS raters are professional energy auditors who have been trained to evaluate a home’s energy efficiency. There are approximately 4,000 HERS raters in the United States. HERS ratings are becoming increasingly popular as more and more homeowners look for ways to save money on their energy bills. A HERS rating can help a homeowner understand where their home is wasting energy and what improvements can be made to increase its efficiency.

The Home Energy Rating System (HERS) is the most widely used residential energy efficiency rating system in the United States. Developed by RESNET in 1995, HERS provides a relative measure of a home’s energy efficiency and carbon footprint compared to a reference home designed to meet minimum building code requirements. The lower a home’s HERS Index Score, the more energy efficient it is in comparison to the reference home.

To complete a full HER rating, the rater will need to model the home on energy modeling software and perform two site visits to complete the required testing to make the calculation of the HERS rating. The testing can take anywhere from a few hours to a full day, depending on the size and complexity of the home. The number of rooms, the layout of the home, and the type of heating and cooling system all play a role in how long it takes to complete testing.

A good HERS score will vary depending on the climate conditions of the home’s location. In general, a score below 50 means that the home is more energy-efficient than average, while a score above 100 means that the home is less energy-efficient than average. A typical new home has a HERS score of around 85, while a typical resale home has a HERS score of around 115.

The International Energy Conservation Code (IECC) is a model code produced by the International Code Council. It establishes minimum requirements for energy efficiency in new and renovated buildings. The IECC has been adopted by most U.S. states and local jurisdictions as the energy code for new construction and major renovations of residential and commercial buildings.

The International Energy Conservation Code (IECC) is a model code produced by the International Code Council (ICC). It provides minimum requirements for energy-efficient building envelope design and thermal system sizing in order to achieve greater energy savings in residential and commercial buildings. IECC standards are adopted by states and local jurisdictions as part of their building codes.

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The IECC is a model code produced by the International Code Council (ICC) that provides minimum requirements for energy-efficient building design and construction.

The IECC is designed to be adopted and enforced by state and local jurisdictions as a means of achieving compliance with federal energy efficiency standards. The code is updated every three years through a consensus-based process involving representatives from a variety of stakeholders, including builders, code officials, architects, engineers, and manufacturers.

The answer to this question depends on the specific location within the state of Texas. The majority of the state is under the 2015 International Energy Conservation Code (IECC), with a few exceptions. Many jurisdictions have adopted the 2021 IECC, and a handful of others have chosen to remain on an earlier code version.

The International Energy Conservation Code (IECC) is a model code developed by the International Code Council (ICC). It is the most widely used code for energy efficiency in buildings in the United States. The IECC is adopted by states and local jurisdictions, typically as part of the building code.

Information Bulletin 167 is a public information document released by the City of San Antonio. The document provides an overview of the city’s regulations concerning the residential energy inspections within its jurisdiction. Information Bulletin 167 is available online at the City of San Antonio’s website. Or simply google IB167 COSA and the recent document should pop up.

The City of San Antonio has adopted the IECC 2021 energy codes.

Three of the compliance paths require meeting certain mandatory provisions of the 2021 IECC, while the fourth path uses RESNET allowed by the State of Texas. Depending on which energy compliance you choose, it will determine what kind of inspections need to be added for your building permit. The Residential Energy Compliance Form (2021 IECC) is linked to Information Bulletin 167 and can be completed online as a pdf to pass those checks.

If you are a licensed general contractor in the state of Texas, then you are required to complete the IB 167 inspection to close out permits for new home construction and additions. The IB 167 inspection is a comprehensive examination of the energy aspects of a dwelling.

This Information Bulletin (IB) 167, which was originally created as a customer service project by the Development Services Department (DSD), has been re-written to meet the requirements of the 2021 International Energy Conservation Code (IECC). The Information Bulletin has been updated to clarify requirements for the City of San Antonio.

Not every building in San Antonio needs to be IB167 compliant, but all new construction and major renovations must meet the requirements outlined in the International Building Code (IBC). The IBC is a model code that provides minimum standards for the design, construction, alteration, and repair of buildings and structures.

To become ENERGY STAR certified, your product must meet certain energy efficiency criteria set by the EPA. The process begins with an application followed by a review of your product’s energy use and performance data. If your product meets the necessary requirements, it will be awarded the ENERGY STAR label.

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HERS Ratings

What is a HERS Rating?

At Lone Star Energy Efficiency, we offer RESNET Home Energy Ratings to San Antonio and the surrounding areas. A HERS rater provides a preconstruction energy analysis of your building plans, the onsite pre-drywall inspection, and blower door and duct leakage testing.

We use your blueprints and energy efficiency software to determine your projected HERS. This software can also determine code compliance and forecasted energy usage. The San Antonio home builder can then use this information to decide on HVAC equipment and establishment products installed at their project to achieve higher HERS scores.

Our certified team at LSEE will then perform pre-drywall and duct leakage testing to determine that every air sealing and insulation measure has been made to meet thermal and air sealing requirements. Duct leakage is performed during this stage to ensure that your air ducts will meet minimum requirements earlier in the project, and to give ample time for subcontractors to come back out to make repairs.

Once all testing has been performed, LSEE will give a HERS score based on the HERS Index.

What is the Home Energy Ratings (HERS) Index Score?

The HERs index is a rating that is between 0-150, with the typical standard home being at 100 (built to 2006 energy efficiency standards). The smaller the HERS score, the more energy efficient the home is. This report can be very helpful in Texas due to the year-round high temperatures and high energy bills.

According to RESNET, a home with an index score of 70 is 30% more energy efficient than the standard reference home.

If you are looking to purchase a home in the San Antonio area, look for a HERS (Home Energy Raters) Index score! Contact our certified energy rater at LSEE, and we’ll use our energy rating system to ensure energy code compliance. We take pride in all the jobs we perform throughout Texas as third-party inspectors for energy efficiency. 

Data Driven HERS Raters in Texas

Things to know before you start on your next HERS in Texas:

  1. A certified HERS rater will start with a building plan review of your upcoming new construction project
  2. Ratings require a pre-drywall inspection that occurs right before installing your drywall and completing all of your air sealing and insulation.
  3. Blower door testing and duct leakage testing are a required part of the process and are performed when the project is completed.
  4. Check with a HERS raters company while you are planning to start a build because you could earn tax credits if a few additional steps are taken.
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Energy Rating Index

The Energy Rating Index (ERI) performance path gives builders yet another option for complying with the International Energy Conservation Code (IECC). The ERI performance path also requires builders to achieve the mandatory code requirements of the IECC, including water heating piping provisions, and comply with the minimum insulation and window envelope performance requirements of the 2009 IECC. The benefits of such performance path include energy bill savings as well as adding to a property’s resale value.

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ENERGY STAR Certification

What is an ENERGY STAR Certification?

Energy Star certified buildings help save money, energy, and protect the environment! Energy Star certified homes must meet a stricter set of energy performance standards.  At Lone Star, we can help you meet these standards by walking you through the process. We serve San Antonio and any surrounding area. 

The Energy Star process starts during the planning stage, requiring a specific type of framing, insulation, HVAC, and other standards that you do not see on standard code construction. Through the energy star process, there will be an onsite framing inspection, the onsite pre-drywall inspection, blower door, and duct leakage testing.

If you are interested in this certification, check out the Program Requirements page for the Energy Star overview to get a head start on your project.  Within this page, you will see that National Version 3.1 does have mandatory requirements that the builder and HVAC installer must meet.

Call now to find out how you can get started on your certification!

Why get your home ENERGY STAR certified?

ENERGY STAR impacts many homes by being 10% more efficient than built-to-code homes and having a better resale value (energystar.gov). With the San Antonio heat, electric bills are high due to the air conditioning trying to keep up. By meeting the requirements Energy Star created, homes are more environmentally friendly and improve the indoor air quality for their owners.

With the passing of the Inflation Reduction Act, the government will also be incentivizing builders with resources to build Energy Star homes with the extension of the 45 L tax credit. This new Tax credit is for homes built on or after January 1, 2023.

Energy Star Scores

The Energy Star Scores are rated on a 1-100 scale. The higher the score indicates that a building is a more efficient place than others. A score of 50 shows median performance, while greater than 75 indicates you’re a top performer and eligible for this certification due to your energy efficiency.

What are the Energy Star Resources?

Energy Star is a voluntary program created by the Environmental Protection Agency (EPA) to help consumers save money and protect the environment through energy-efficient practices. To be certified in Energy Star, a home must meet strict energy efficiency guidelines set forth by the EPA for you to get the certifications. These guidelines are designed to encourage the development of an energy efficient home that uses less energy, save money, and help protect the environment. To ensure that homes meet the Energy Star guidelines, the EPA conducts independent audits of homes that have been certified. The audits are designed to ensure that certified products and homes continue to meet the Energy Star guidelines. As a result, an energy Star-certified home uses less energy than a standard home or any buildings, which results in savings for consumers and helps to protect the environment. Reach out to our San Antonio team at LSEE so we can make your home Energy Star Certified.

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Certified Insulation Inspection

For new and existing mechanical systems, Certified Insulation Inspectors will inspect and verify that both materials used and the total insulation system are installed correctly in accordance with project specifications. They also can identify areas of concern with previously installed insulation systems.
Certified inspection of mechanical insulation systems will help reduce costs proven to be associated with non-compliance with mechanical insulation specifications (material and installation) and lack of proper and timely maintenance.

Certified inspection will also support energy savings, reducing emissions, and occupational and process safety initiatives, helping reduce the need for potential additional capital funds due to corrosion under insulation and other problematic occurrences.

The inspectors have been certified by the National Insulation Association (NIA) and utilize the inspection principles during the inspection process.

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Blower Door Test

Do you need to schedule our blower door testing services? Contact us today!

What is a blower door test?

A blower door is a useful tool to analyze and diagnose energy loss in a building.  It consists of a powerful fan that mounts into the frame of a doorway to the exterior of your home. Once the fan is turned on you will be able to measure the amount of air leaving the home in Cubic Feet per Minute (CFM). A qualified energy professional can calculate the specific target CFM for your house. 

Through our blower door tests, you will be able to physically feel the air coming through any gaps in the exterior envelope of the house. You can even feel the air with your hands while the fan is moving. 

Our team will use the fan to discover weak spots in your building envelope and get a baseline for any repairs that need to be made. 

Why is a blower door important in your home?

According to Energy.gov a blower door is important because it:

  • Reducing energy consumption from excess air leakage
  • Avoiding moisture condensation problems
  • Avoiding uncomfortable drafts caused by cold or warm air leaking in from outside
  • Controlling outdoor contaminants, pests, and odors from entering your home.
  • Determining proper sizing and airflow requirements of heating and cooling equipment.
  • Determining whether mechanical ventilation is needed to provide acceptable fresh air and maintain indoor air quality in your home.

Whether you are a residential homeowner looking to find out where you are losing energy, or a home builder looking to meet your local code, our blower door testing is a vital test for your building. Reach out to our San Antonio team for any of our energy efficiency services.

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Duct Pressure Testing

Duct pressure testing identifies energy loss through leaks in your ductwork. Ensure your dollars are not flying out your window! With our duct blaster machine our energy professionals will diagnose any air leakage inside a home’s air ducts. This leakage is measured in Cubic Feet per Minute (CFM), and a duct blaster is used to find this measurement.

The Duct Blaster will pull air out of the duct system (depressurize) and through the fan. The amount of air that is measured is the amount of leakage in the ducts.

To set up our testing, a technician will cover up all of the supply and return air registers in the house with tape or a cover. Then the duct blaster will be connected to the return register with tape. This process usually takes around 30 minutes to set up. Once all registers are sealed, the technician will turn on the machine and read the results on the manometer gauge.

Blower Doors:
Blower Doors testing identifies energy loss through leaks in your structure. The test ensures your house is not leaking energy. It consists of a powerful fan that mounts into the frame of a doorway to the exterior of your home. Once the fan is turned on you will be able to measure the amount of air leaving the home in Cubic Feet per Minute (CFM). A qualified energy professional can calculate the specific target CFM for your house. Through our blower door tests, you will be able to physically feel the air coming through any gaps in the exterior envelope of the house. You can even feel the air with your hands while the fan is moving.

Our team will use the fan to discover weak spots in your building envelope and get a baseline for any repairs that need to be made. This is important for the following reasons:

  • Reducing energy consumption from excess air leakage.
  • Avoiding moisture condensation problems
  • Avoiding uncomfortable drafts caused by cold or warm air leaking in from outside
  • Controlling outdoor contaminants, pests, and odors from entering your home.
  • Determining proper sizing and airflow requirements of heating and cooling equipment.
  • Determining whether mechanical ventilation is needed to provide acceptable fresh air and maintain indoor air quality in your home.
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Building Inspections for Safe and Compliant Construction

We are a trusted partner with the City of El paso for building a better environment. We provide building code compliance inspections to provide a reasonable level of safety, public health and general welfare with regards to the structure.

This can be accomplished through structural strength, means of egress facilities, stability, sanitation, adequate light and ventilation, energy conservation, and safety to life and property from fire and other hazards attributed to the built environment. It also outlines the minimum requirements to provide a reasonable level of safety during emergency operations.

Our team spends considerable time inspecting worksites to ensure that construction meets local and national building codes and ordinances, zoning regulations and contract specifications.

With a thorough understanding of the complexities of code compliance and constantly evolving statewide regulations, our technicians and inspectors utilize their many years of experience to ensure a smooth permitting and construction process.

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Renewable Energy Certificates

We offer Renewable Energy Certificates, this official documentation proves that one megawatt-hour (MWh) of renewable energy has been added to the energy grid. RECs can be used to meet voluntary goals, including RE100 and CDP commitments, or compliance obligations such as renewable portfolio standards (RPS).

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Whole House Heat Load Calculation

We offer Manual J heat load calculation. This will calculate how much cooling is needed for the summer months and how much heating is needed for the winter months. Our easy, affordable Manual J takes the guesswork out of your projects heating and cooling needs!

We make getting your HVAC permits easy and painless!

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REScheck Compliance Report Preparation

We offer REScheck report preparation. Preparing a REScheck Report is one method for validating compliance with the IECC Building Code (International Energy Compliance Code). These reports can be performed on new construction homes, remodels or additions. Our staff of energy code specialists includes HERS Raters and Manual J/D Report Specialists. We can perform REScheck reports from plans allowing you to focus on what you do best – designing and building homes.

 

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