Tag Archives: Blower door

Tools of the Trade Part III

Our previous post focused on the infrared thermal imaging scanner that we use to detect air infiltration into new and existing homes.

Infrared Scanner

Infrared Scanner

In this post we’ll focus on another of the diagnostic tools of the trade that we use to verify supply and return-air efficiencies in forced-air heating/cooling systems.

We use the Minneapolis Duct Blaster to perform a “Total Leakage Test” of the duct system.

Duct Blaster

Duct Blaster

The Duct Blaster is a device that uses pressure testing to find the amount and location of air leakage in a duct system.
To do the test, we seal all outlets except for one on the return side of the system. This is the side that returns stale air to the furnace to be reconditioned. The Duct Blaster is connected to this return-air opening and then turned on to blow air into the ducts. The air goes through the return ducts to the air handler and then through the supply ducts. If the duct system is very tight, it doesn’t take much airflow through the fan to pressurize the ducts. If you have a big leak, like a disconnected plenum or duct, it will be next to impossible to pressurize the ducts adequately.  This would be like trying to pump air into a tire that has a big hole in it.

The process yields quantitative results because testing requires two pressure measurements: one inside the ducts and the other inside the fan. The first allows the tester to compare results from different systems by always pressurizing to the same level. The second measures the airflow in the fan when that level is reached. As mentioned above, tight ducts means low airflow, and leaky ducts require lots of airflow.

Pressurizing only the ducts determines the total leakage. That includes the air that escapes into the conditioned space and the air that leaks to the outside of the building envelope (i.e., the attic or crawl space). The latter is the most important part because you derive no benefit from it. To separate it from the total leakage, we pressurize the house to the same level as the ducts by using the Blower Door. Then, when the Duct Blaster brings the ducts up to the required pressure, none will leak to the inside of the house because it’s at the same pressure as the ducts. The fan only has to blow enough air in to make up for the leakage to the outside, and that’s the amount that’s important.

This is a picture of the blower door ready for use.

This is a picture of the blower door ready for use.

In a tight air distribution system, the leakage to the outside (in cubic feet per minute, or cfm) will be 5% or less of the square footage of the home. Most new installations start at about 15% to 20%, and go downhill from there. At those rates, a third of the heating and cooling bills could be a direct result of duct leakage.

After performing a Duct Blaster test to determine the amount and locations of air and duct leakage, we seal up the leaks that we find. Upon completion the house and/or duct system will perform better, and your heating and cooing bill will be lower.

You can follow this link to a you tube video part 1 of 4 videos.
http://www.youtube.com/watch?v=sk-A08zsguE

As they say at Focus on Energy, “Testing Trumps Talk” and we couldn’t agree more.
By testing and  verifying the tightness of the building envelope and the duct systems in our high-performance homes, we are able to identify any deficiencies and take corrective measures.

Lower operating costs, greater comfort, safety, durability and higher resale values are just a few of the benefits realized by implementing building science principles and best practices into the homes that we build.

By testing, inspecting, and documenting the quality of work, we bring a higher level of added value and peace of mind for our clients.

The Duct Blaster is another diagnostic tool of the trade that helps us in delivering the added value that is built-in to our high-performance homes and remodel projects.

If you’d like to learn more about how we can provide added value to your new home or remodel, please visit our website and contact us.
http://www.greatlakescarpentry.com

In our next post, we’ll talk about mechanical ventilation, exhaust equipment and the diagnostic tools of the trade that we use to verify performance and efficiency of this critical component of the high-performance homes we build.

Great Lakes Carpentry is “Building Today for a Greener Tomorrow.”

 

Tools of the Trade Part II

In our previous “Tools of the Trade”post we focused on the “Blower Door.”
The blower door is the device that we use to simulate a 20 mph wind coming at the home from all directions, simultaneously.

This is a picture of the blower door ready for use.

This is a picture of the blower door ready for use.

We talked about the blower door being a peripheral of the laptop computer that is used, the software and the pressure and flow gauge that help us in gathering the data that tells us how air-tight the home is.
We showed you one of the low-tech tools used to locate specific areas of air-infiltration, the smoke stick.

This week we want to show you the high-tech version of this “Tool of the Trade” that we use to locate specific areas of air-infiltration, the Infrared Scanner/Camera.

Infrared Scanner/Camera

Infrared Scanner/Camera

In the hands of someone that’s been trained in the science of infrared imaging (Thermography), such as our Home Performance Professional, this is a very powerful tool of the trade.

Once we’ve depressurized the home to 50 pascal by running the blower door, we use the IR scanner to locate any air-infiltration, by scanning all of the “usual suspects” for air-infiltration.
We scan all exterior walls, window and doors, roof assemblies and where the roof assembly meets the exterior wall.

Scanning for Air-Infiltration

Scanning for Air-Infiltration

We are able to take pictures of the images that the IR scanner produces and attach the images to the reports that we generate for review by our carpentry crew, our insulation trade contractors and by our clients.

When we enroll an existing home in the Home Performance with Energy Star program, we refer to this testing process as a “Whole-House Energy Assessment”
We use this information to determine deficiencies in the existing homes that we test, so we can define the scope of our work for taking corrective measures.
We refer to this initial test as “Testing In.”
The homeowner is provided with the performance data compiled during the initial test and with a “Prescriptive Path to Remedy” any existing deficiencies.

Once the owner of an existing home approves the scope of work necessary to correct deficiencies, we perform the corrective work and then we “Test Out.”
By doing so, we provide the homeowner with improved performance data and documentation that they’ve done due diligence in improving the efficiency and performance of their home.
This leads to more than a lower energy bills, greater comfort and a healthier indoor environment. It leads to higher re-sale values.

We use these same tools of the trade and methods to test our new homes as well.
Here in Northern Wisconsin, we enroll the new homes that we build in the “Focus on Energy New Homes Program.
The performance data that we gather by testing verifies that we’ve met and in most cases, exceeded program standards for certification.
As the folks at Focus on Energy say, “Testing Trumps Talk.”
We don’t expect our clients to simply take our word on how efficient their homes are.
We put science to work and third independent testing services to verify the efficiency of the homes that we build.
At Great Lakes Carpentry, we believe that by building to higher performance levels and testing our projects, we provide. much more than just added value.  We provide peace of mind by using science to prove that what we’ve done was done right.

What we’ve shown so far are just a few of the “Tools of the Trade” that we use for testing our high-performance new homes and energy remodeling work that we perform.

We’ll showcase some of the other tools of the trade in our next post.

Passive House

History

Super energy efficient homes are not a thing of the future, but rather a blast from the past.  The Passive House standard was developed in Germany by a physicist Wolfgang Feist in 1996. His inspiration came from the super insulated homes that were being build in the 1970s in the United States and Canada. Now, upwards of 20,000 Passive Houses have been built in Europe while the U.S has built less than two dozen.  A few reasons why this idea did not catch on 40 years ago was because the technology for high performance windows, doors, and ventilation systems were not quite there yet. Politics is also another factor, and still is an important factor when talking about energy efficient building practices. If politicians don’t understand or believe energy efficient building standards are important than its hard to make any progress in the building industry.

Main Goal

The goal of a Passive House is to maximize solar gain. This is achieved through a virtually airtight building envelope, mechanical ventilation, triple-pane windows, and eliminating thermal bridging. The three requirements that a Passive House needs to meet include: Air Infiltration, Btu consumption, and Energy usage.  If these requirements are not met or there is a slight mistake, the home will not acheive the title of Passive House.

Main Advantages

Passive House performance based building standard can result in a home that consumes as little as 10% of the total heating and cooling energy.

Doesn’t fall into the trap that electricity production is better done on the roof.

A Passive House is planned even before the contractor breaks ground. Contractors and the home owner know exactly how much energy the home is going to consume once it is built, and how much it is going to cost of operate.

One of our most recent projects (pictured above) which we refer to as the “Energy Sipper” achieved Passive House air-tightness standard and a HERS score of 37. To learn more about how we can help you get into a super-energy efficient home visit the  Great Lakes Carpentry website. Like us on Facebook, also follow us on Twitter!

If you missed our article last week Net Zero: The Next Frontier check it out. You can also compare and contrast the differences between Passive House and a Net- Zero energy home by visiting Green Building Adviser. If you would like more information about Passive House, check out this PDF.

 

 

Home Performance Testing

It is hard to tell what is wrong with a home or how much energy its using just by looking at it.  The only way to tell how energy-efficient a home is, is by running numerous tests using various diagnostic tools.   This is where we put science to work to tell us exactly what is going on in your home.  Whether you are building a new home or are remodeling, we recommend bringing in a third-party to test the home.  If you are building a new home, this ensures your home is built right from the start; or if you are remodeling, will tell you where your money is literally slipping through the cracks

Diagnostic Tools
To learn more about these tools click HERE.

Blower Door:A blower door is the tool used to specify how air tight the house is.

This is a picture of the blower door ready for use.

A blower door is a variable speed fan that pressurizes and depressurizes the house to measure air leakage. The blower door is placed in the front door of the home and will simulate a 20 mile per hour wind that is coming at the house from all directions. It will suck all the air out of the home and tell you exactly where air is leaking and will tell you how air tight the home is.  It takes about 15 minutes to set up a blower door and test a new home. Testing an existing home could take 30 minutes to an hour, because there would be more leaks to identify.  If you would like to watch a video about the blower door process click HERE.

Infrared Camera: An infrared camera is a thermal imaging tool that makes an

Rich Urban of E3 Home Performance scanning the home for air leaks.

image that shows surface heat variations that can be used to help detect heat losses and air leakage in buildings. It will show exactly where air is coming in and out of your home.  This is important in the building process so these holes can be properly sealed to prevent air leakage.  On an existing home, it will pin-point holes that need to be properly filled.

Manometer: This instrument measures the pressure differences between two locations. If you have an air tight home, this tool is very useful because it’s used to test combustion appliances such as a water heater.  We want to make sure these appliances draft properly to ensure harmful chemicals won’t leak into your home.

Duct Blaster: This is another variable speed fan that evaluates the leakiness of the duct system. This tool is used more in warmer geographic regions because those homes will use cooling systems more.

Flow Hood (balomeater):  This device tells us the amount of air flowing through a register. Tell you how much air is moving through, exhaust fans that would be located in your home. Ventilation is very important when building or maintaining an air tight home, because it will prevent mold from going in places you don’t want mold to be.

Why This Test is Important

1. It will ensure that you are building your home right the first time.  For an existing home, it will tell you exactly what you need to do to fix the problems.

2. It is proof that your home is energy-efficient and up to the highest building standards. This will make your home more valuable if you do decide to sell it.

3. After all is said and done, you will save money on your heating and cooling costs.

E3 Home Performance

Rich Urban is the president of E3 Home Performance.  He works with Great Lakes Carpentry along with 6 to 7 other contractors in the Northern Wisconsin area as a third party consultant to perform an “energy audit.”  He works with your contractor to help find and fix defects in your home.

If you would like more information about what he does or have any questions about the process you can contact him directly via email or telephone.
Email: richurban@charter.net
Phone: 715-369-7390