Carbon Monoxide Investigator on a Construction Site

Corbett Lunsford’s building inspection of a huge development is interrupted when he feels compelled to show you:
#1. How ridiculously huge this space heater is
#2. Proof that the worksite is safe according to air quality standards
Stop guessing. Proof Is Possible. Ask for it.

You might think it’s obvious when someone is being poisoned by carbon monoxide (CO). You might think your furnace simply must be replaced with a newer model if you have CO showing up in your home. You might think the $20 CO detector you bought will protect your whole family from the possibility of either of the above. WRONG on all counts!

“The amount of misinformation about carbon monoxide isn’t surprising, since the gas is everywhere around us- coming out of our vehicle exhaust, our furnaces and water heaters and ovens and stovetops,” says Corbett Lunsford, Exec. Dir. of the IL Association of Energy Raters & Home Performance Professionals (IAER). “Everyone takes pride in knowing something about everything- too bad most conventional wisdom about carbon monoxide is B.S.”

First, let’s look at the symptoms of carbon monoxide poisoning: “flu-like” is how they’re usually described. Ask yourself: have you ever had “flu-like” symptoms? Have you ever been to the doctor because of them? We can safely bet that the answer to both questions is YES. Now ask yourself: has a doctor even once suggested testing you for carbon monoxide poisoning? The answer to that is a solid NO, 99.9% of the time. Doctors are conditioned day in and day out to seek the simplest solution for what ails you, and prescribe medication to fix it. Indeed, that is all we demand of our doctors- if they suggest further testing, we understandably press for the easier option in pill form and try to get the hell out of there. Nowadays, however, testing for CO poisoning is as easy as placing your finger in a medical LED device- no syringes or blood samples necessary.

Second, let’s look at how carbon monoxide is created: a something that burns fuel isn’t working correctly. It’s called “flame impingement” and it happens when the fuel isn’t burned completely because something’s in the way- dust, or metal, or a pot of water. Yes, that’s right- every time you make tea on a gas stove, you’re also making carbon monoxide. Should you avoid ever making tea again? Of course not! CO is a natural byproduct of driving, getting warm, making tea, and on and on- the trick is to make sure it doesn’t get into the air you’re breathing. That’s what the kitchen exhaust fan, the chimney, and the rear exhaust pipe is for. If your kitchen fan is a recirculating type (meaning you can feel the fan blow the air out above the stove), then it’s totally useless for its intended purpose, and sadly you’re not alone. Millions of kitchens don’t have exhaust fans connected to outdoors, because people who build kitchens generally don’t understand carbon monoxide either!

Lastly, let’s look at the carbon monoxide detector that’s hopefully installed somewhere in your home. You trust it- it says “UL-listed” whatever that means, it’s what everyone else seems to be using. Well, as with so many things, it’s important to read the instructions- in this case, you’ll see a warning that basically states: “this detector is designed to protect healthy adults from acute poisoning. It will alarm if the CO level is over 70 parts per million (ppm) for over an hour, and if you have anyone in your home who’s NOT a healthy adult, you should buy a better detector.”

That’s right: children, pregnant women, elderly and ill people all experience the toxic effects of carbon monoxide at levels as low as 9 ppm. Additionally, recently a fourth study was published pointing to a link between traffic pollution and autism (Epidemiology, October 2014). But don’t panic, there’s a solution!

The instructions in your CO detector also state that you should have your furnace and water heater (as long as they’re not electric) tested and maintained annually- get a BPI or RESNET-certified professional to run standard diagnostics on the CO level created by your appliances, and make sure they’re all being successfully evacuated outdoors. Also, have a blower door and zonal pressure test run to ensure that your attached garage doesn’t have a significant air connection to the house- a tragic flaw in most homes that becomes obvious when the car is accidentally left running inside. For a list of professionals in the Midwest, visit: http://ilenergyraters.org

And protection of children, pregnant women, elderly or ill individuals is simple with a Low-Level CO Detector (such as the Defender and a growing number of other brands) that’s NOT UL-listed. These alarms will sound immediately in response to small amounts of carbon monoxide. If your alarm sounds, make sure to first have a whole-home professional run tests on the dynamics of your home. Don’t immediately replace your furnace- it might be caused instead by any number of other factors, which home performance diagnostics can pinpoint and help you fix for good. You might not “get the flu” for years!

Five Years of Home Performance Testing Data from Our Clients

We see a lot of houses. We have a lot of data on houses. For a while now, I have been wondering whether or not I’d be able to find some meaningful relationships with this data. I am not even sure what I would use it for, but I have taken some time to compile the data and pull some numbers that I thought were interesting. More than anything, the data just shows typical values for ‘regular houses’ in the Chicagoland area.

DISCLAIMER: This isn’t a scientific research study in any way, shape, or form - there are many things that you may point out that would make this little ‘research project’ invalid. I randomly selected 98 properties that we have done some sort of analysis for over the years. These properties were a mixture of single-family homes, condos, and townhomes. All of them were in the general Chicagoland area and were not built/designed to be high performance.

Here is a quick glimpse at some of the home size statistics from our sample:

Metric: Largest/Smallest/Average

Size (Square Feet): 9,058/1,155/3,963

Volume (Cubic Feet): 86,866/11,459/34,305

Enclosure Area (Square Feet): 21,723/2,079/7,565

Shell Area/Volume: 0.35/0.15/0.23

The SA/VOL is a ratio of the surface area of a building to its volume. Generally, ‘efficient’ shapes have large volumes with low surface areas, therefore making this ratio as small as possible. In European countries, this metric is often a key design consideration. Most homes in Chicago will have a SA/VOL ratio of 0.2-0.23 because of long, slender lots (typically 20’ wide and 55’ long).

Now lets talk about some consumption statistics and how they relate to home size:

Metric: Largest/Smallest/Average

Square Feet per Ton of Air Conditioning Installed: 1886/390/878
SF/Ton AC: The number of square feet of the home divided by installed capacity of the cooling equipment. 1 Ton is approximately equally to 12,000 Btu/hr.

% Air Conditioning Installed Compared to Amount Actually Needed in Home: 177%/-54%/21%
% AC Size Discrepancy: The % difference between the capacity of the installed cooling equipment and the calculated amount needed from an energy modeling software.

Square Feet per kBtu per hour of Heating Installed: 95/13/31
SF/kBtu Heating: The number of square feet of the home divided by installed OUTPUT capacity of the heating equipment.

% Heating Installed Compared to Amount Actually Needed in Home: 157%/-47%/34%
% Heating Size Discrepancy: The % difference between the OUTPUT capacity of the installed heating equipment and the calculated amount needed from an energy modeling software.

Annual kiloWatt hours per Square Foot: 9.39/0.68/4.01
Annual kWh/SF: The actual electrical consumption over a year long period divided by the area of the home.

 It should be noted that square footage, installed equipment capacities, and annual kWh are actual measured values, or determined through inspection. The % discrepancy between installed equipment and calculated loads is based off an energy model, so these values have inherent errors in them because of this. Regardless, the results are pretty typical with standard construction – heating and cooling equipment is usually oversized for the needs of a given home (positive % indicates oversized, and negative % indicates undersized).

Lastly, I’d like to point out the variability in annual electrical consumption in relation to home size.

Electrical consumption is largely based on occupant behavior, installed gadgetry, and family size. Typically, the phone calls we’d receive regarding large electrical bills were pretty simply explained by a few big consumers like pool/hot tub heaters, pumps, electric radiant heat, and entertainment systems.

In closing, the information provided here gives you an idea of standard homes in Chicago. I am not a fan of ‘rules of thumb,’ so the above metrics aren’t intended for any form of comparison against new homes. The overall idea is always to engineer a perfect home, install all components to specification, and test them once they are in place. Or as Corbett Lunsford would say it, ‘Control is the goal.”

Passive House Explained in 90 Seconds

This video’s not one of ours, but we love it so much! If you’ve heard of Passive House (or Passivhaus) building certification, this entertaining little video breaks it down nicely! Since I just became one of the first Passive House Raters in the Midwest, we hope to be doing more and more passive construction projects soon.

Passive House Explained in 90 Seconds from Hans-Jörn Eich on Vimeo. Thanks to Hans for creating this Passive House video!

I'm a Passive House enthusiast. I'm involved in this great movement to create highly energy efficient buildings that use 80 to 90% less energy. But how? I get asked often what a Passive House is. This is the low down in 90 seconds.

New BPI Exam Prep Promises Higher Certification Rate

July 12, 2013 – Chicago – Standards for the home improvement industry have been given another push up the ladder with the launch of BPIexamprep.com . The online training, from Home Performance Diagnostics author Corbett Lunsford, is designed as a supplement to BPI Training or for professionals who need to self-study due to limited time, budget, or access to training.

Homeowners and government programs alike have been demanding a growing army of BPI Certified contractors , and even building codes are now recognizing the certification for new home quality control. "BPIexamprep.com has been years in the making, and something I wish I’d had when I was getting ready to challenge these certification exams," says Lunsford. The modular, self-paced video course offers students all the information needed to put the finishing touches on preparation for any of the main five BPI Certification exams: Building Analyst, Envelope Professional, Heating Professional, A/C and Heat Pump Professional, or Multifamily Building Analyst.

While BPI Exam Prep is not meant to take the place of a week-long hands-on BPI Training, it does help students pass the exams the first time. Many people who seek BPI certification have been out of school, and out of the habit of test-taking, for years. "BPI exam sets have a standard price of $750, so it can be expensive to have to re-take these tests," laments Lunsford. "I got sick of watching other school’s students fail these exams on their first try, simply because they didn’t know what to expect. The psychology of test-taking is a huge hurdle, and this course helps students get over it."

The online course is self-paced, interactive, and includes 6 modules: 5 guidance videos from Lunsford and a 100-question practice BPI exam. After having trained hundreds of BPI Certified Professionals, and proctored hundreds of BPI exams, Lunsford and his Building Performance Workshop are standing up for students everywhere, and giving them the edge they need to ace the test.

FOR A FREE, INTERACTIVE VIDEO GUIDE TO BPI CERTIFICATIONS, OR TO GET A TOUR OF THE COURSE, VISIT:
http://bpiexamprep.com

Ventilate it right, and Ventilate it Right. Did I say Ventilate?

We recently ordered ourselves a copy of the new ASHRAE 62.2-2013 standard and today I spent some time sifting through the madness.

In Illinois, this is becoming a pretty regular topic of discussion since all new construction requires mechanical ventilation. Plenty of our clients are still using exhaust only ventilation under the 62.2-2010 standard, but as Joe Lstiburek pointed out in this article, it doesn’t always work as planned. And as an energy modeler, I personally know that designers who use exhaust only ventilation with the new standard are going to be hit hard with some serious energy penalties from the increased rates. While this is not meant to be totally encompassing, here is a quick synopsis:

• Mechanical vent rates have been increased to a total ventilation base model of  7.5cfm( Bedrooms+1) + 0.03cfm(Floor Area) and no longer assume default leakage of 2cfm/100ft^2
• In order to take credit for infiltration, a blower door must be performed, and Effective leakage area, Normalized leakage, and effective annual average infiltration rate must be calculated. The required mechanical ventilation rate is the difference from the total ventilation and the effective annual average infiltration rate [the effective annual average infiltration rate must be NO GREATER than 2/3 of the total ventilation rate]
• 2013 standard assumes no ‘reasonable’ leakage in multifamily buildings
• CO alarms are now required in all dwelling units
• Similar to previous standards, does not address unvented combustion sources, material off-gassing, smoking, etc…
• Thermal comfort not considered in ventilation strategies
• Ventilation rates must be measured and net ventilation must meet the required ventilation
• When atmospheric OR solid fuel burning appliances are within pressure boundary, the net sum of the two largest exhaust fans must not exceed 15cfm/100ft2. If this occurs, capacity must be reduced or outdoor air must be introduced.
• Ducts/air handlers outside the envelope must be sealed to reduce leakage to a rate of 6% of total airflow when tested at 25Pa
• Mechanical systems that supply air though 10 or more feet of ductwork AND through a thermal conditioning component require a minimum MERV 6 filter
• Multifamily dwelling units must meet the total ventilation rates of a single family home, with no credit for infiltration
• Corridors and common areas of multifamily buildings must be ventilated to 0.06cfm(Floor Area)
• Existing building shall be ventilated to the total ventilation as described above and no credit for infiltration may be used unless it is tested. If the credit for infiltration is greater than the total required ventilation, no ventilation is required.

In short, what this says to me is that all buildings need to be tested with a blower door to take advantage of the infiltration credit, and that all ventilation systems should be balanced (meaning supply outdoor air = exhaust air) with heat/enthalpy recovery systems. If you on the ground trying to collect all the dropped HERS points you can, you may just have to make some changes to your ventilation design in order to do so. Luckily, blower doors are required in our state already – but calculating that infiltration credit is something that will cause most designers to pull their hair out…