Using Carbon Dioxide (CO2) As An Indicator Of Indoor Air Quality (IAQ) Issues

Evaluating The Carbon Dioxide (CO2) Levels Inside a Home as a Clue For Mold

July 24, 2023

Introduction: CO2 Levels Inside A Home

Regal Home Inspections, LLC has always been as diligent as possible with regard to meeting and often exceeding the letter and spirit of the NJ Home Inspection Standards of Practice (The Law). We’ve received many compliments on the comprehensive nature of our inspections and quality of our reports. The Law states what must be done, what is excluded and leaves open to individual inspection companies to expand into ancillary services. As an example, both of the home inspection team at Regal Home Inspections is, of course, licensed in NJ to conduct the home inspection. They are also both certified by the NJ DEP as Radon Measurement Technicians. Frank is also licensed by the NJ DEP as a Pesticide Applicator which allows him to conduct termite inspections and prepare the industry recognized Termite Report (NPMA-33).  Brian is also licensed by various State entities to perform lead paint evaluations (Lead Safe inspections) and collect dust samples to check for lead paint dust.

As of this writing, New Jersey does not have any license requirements for mold testing, sewer scopes, oil tank sweeps, etc. and we opt to allow others address those. We will, however, evaluate the Carbon Dioxide (CO2) levels inside a home as a clue for mold. More on this below.

A conversation about, “Looking for mold” often takes place with prospective clients and we’re very consistent to say, “We don’t look for mold”.  Mold can be in dozens of places inside a home; Under carpets, inside walls, behind bathroom vanities, etc.  We feel that if you tell someone that, “Yes, we look for mold” then if you look in 100 places and don’t see any it’s possible that after the client moves in and changes the carpets and there’s mold under the padding for a carpet they may complain because you said, “Yes, we look for mold” (Which of course we do not).

Taking air samples for mold is one way of determining if high levels of mold exist inside a home but it’s costly. A special vacuum pump is used to collect air samples. Multiple air samples are taken then sent to a lab for evaluation. The lab’s evaluation includes identifying the types of mold spores collected and the amount. Some mold is expected. Elevated levels are not. Again, each air sample costs the consumer about $125.00 and usually, at least 3 are needed (One of which is a control sample taken outside the home being tested). There may be as many as 6 or more in many instances and the cost can easily approach $1000 just to, see if there’s mold.

Solution CO2 Levels Inside A Home

CO2 meter in calibration mode.
CO2 detector mounted on a tripod. Indoor measurement is 796ppm. Like many homes, the windows and doors have been kept closed for weeks while the AC has been running. Same room after the windows were opened measured CO2 @ 554ppm.“See” if there’s mold.

We have recently learned about another, less expensive way to predict if a home has mold. In researching the new methodology we learned that it has been in use with the US Department of Agriculture for years (Since about 2009).

For the home buyer, it’s predictive. If this new methodology provides normal results then the research indicates that there aren’t elevated levels of mold growth inside a home.  However, if the methodology has different results, that indicates that high levels of mold exist THEN, further evaluation is required by a mold specialist.

The predictive methodology is measuring the Carbon Dioxide (CO2) in the air inside a house, room, basement, etc.  Research that we’ve reviewed state that normal outside CO2 levels are about 400 parts per million (ppm). If the levels of CO2 spike, 3000 or more ppm, this is a red flag that there may be high levels of mold in the house. You see, according to a USDA researcher, ”monitoring CO2 levels might provide more accurate results to detect if mold is growing.  Monitoring mold by measuring CO2 : USDA ARS

The researcher says that,As mold grows it gives off carbon dioxide. Therefore, if there is a CO2 spike, there is likely an increase of mold activity.”

From Facts About Indoor Mold – RadGreen

“Seeing a spike in CO2 levels could show severe mold growth. Standard carbon dioxide runs about 400 parts per million (ppm), and if the sensor reads more than 10,000 ppm, that could mean severe mold activity, and then 2,000 to 3,000 ppm could mean some mold activity.”

“Indoor mold is the mold that causes problems. Mold growth can cause damage to buildings and furnishings. To reduce mold growth in an indoor space, controlling the humidity levels is very important. Keeping humidity levels between 30-60% can reduce the amount of moisture in the air to keep mold growth low.(2) Ventilating the space is another way to reduce mold growth in indoor spaces. Inspecting your indoor space is vital to ensure that the indoor environment stays healthy. Responding quickly to leaks and spills and cleaning them is essential to prevent growth in those areas.”

Regal Home Inspections, LLC, is undergoing the implementation of the use of carbon dioxide (CO2) detectors during the course of our home inspections. Training for Indoor Air Quality was just completed. Just like the termite inspection, radon test or lead paint, it will be another ancillary service allowed by the home inspection Law.  During the course of a home inspection a CO2 detector will be used in different areas of the house. For example, we’ll check the CO2 levels in the basement, kitchen area and bedroom area. If the CO2 is in the 600ppm range then, as the reference material indicates, that’s a level that is expected inside. If it’s elevated from that and spikes to 2000ppm – 10,000ppm then the client will be advised to get a mold specialist for further testing. This service will be offered in conjunction with our standard home inspections at a reasonable price. It will also be offered as a standalone service.

“Seeing a spike in CO2 levels could show severe mold growth. Standard carbon dioxide runs about 400 parts per million (ppm) [outside], and if the sensor reads more than 10,000 ppm, that could mean severe mold activity, and then 2,000 to 3,000 ppm could mean some mold activity.”

“Indoor mold is the mold that causes problems. Mold growth can cause damage to buildings and furnishings. To reduce mold growth in an indoor space, controlling the humidity levels is very important. Keeping humidity levels between 30-60% (20% – 50% is a tighter range which is beneficial) can reduce the amount of moisture in the air to keep mold growth low.  Ventilating the space is another way to reduce mold growth in indoor spaces. Inspecting your indoor space is vital to ensure that the indoor environment stays healthy. Responding quickly to leaks and spills and cleaning them is essential to prevent growth in those areas.”

Regal Home Inspections, LLC, is undergoing the implementation of the use of carbon dioxide (CO2) detectors during the course of our home inspections. Just like the termite inspection, radon test or lead paint, it will be another ancillary service allowed by the home inspection Law.  During the course of a home inspection the CO2 detector will be used in different areas of the house. For example, we’ll check the CO2 levels in the basement, kitchen area and bedroom area. If the CO2 is in the 500ppm to 600ppm range then, as the reference material indicates, that’s a level that is expected. If it’s elevated from that and spikes then the client will be advised to get a mold specialist for further testing. This service will be offered in conjunction with our standard home inspections at a reasonable price. It will also be offered as a standalone service.

 

Pricing:                                                       With a Home Inspection         Stand-alone

Radon                                                          $50 – $100                             Minimum $175

Termite                                                         $50 – $100                            Minimum $195

Lead Paint                                                     Varies*                                 Varies*

Carbon Dioxide (CO2)  Measurement         $150                                       $350+

 

*- Different municipalities have different requirements. Some allow a visual, “Lead Safe” inspection and others require swabs be taken in every area where children are likely to spend time; Bedrooms, playrooms, Living rooms, etc.

 

 

A Superior Effort and Inspection – Part 2

A Superior Effort Part 2

By Frank J. Delle Donne, Licensed Home Inspector

January 10, 2015

For most people, purchasing a house is the largest purchase they have thus far made. Help ensure that you, “Buy with confidence. Sell with pride” ® by using Regal Home Inspections, LLC.

Introduction

On Friday, January 9, 2015 I was hired to conduct an inspection on a nicely renovated 52 year old house. It had been remodeled with updated bathrooms, new siding and despite its age, looked very nice and it absolutely was for the most part. Like the Superior Effort article I wrote in December 2014, I was informed that the house had also been recently inspected. The seller told me that the house had been inspected in the summer of 2014 by another potential buyer. That deal, I was told, fell through because of septic issues but the seller had the septic system replaced following that deal’s demise. I was also told by the seller that the, “only other thing” the other inspector found was an issue with the chimney flashing which they had fixed.

Just like I said in the December 20 edition of the Superior Effort article, perhaps another inspector would have cruised the rest of the way home on this second inspection but I did not. Following are some examples as to why, in my humble opinion, you should hire Regal Home Inspections, LLC to perform your new home inspection.

Examples

Here are some of the items that I found during the inspection that the, “other” inspector should have found.

1) The New Jersey law that oversees home inspectors requires that home inspectors test the, “Entrapment Protection Mechanism” for garage doors. This includes the photo-eye beams mounted close to the floor on the garage door tracks and the auto reverse in the event something gets caught under the door as it’s closing. One garage door had the photo-eye but the other did not. Additionally the doors required adjusting on the down-force-tension because they did not reverse when tested. Starting in 1993, garage door openers had to come with these safety features. It should be reported if they aren’t installed or operating in a home inspection report.

2) New Jersey Home Inspection laws follow the Standards of Practice of the American Society of Home Inspectors (ASHI). ASHI is actually mentioned in the NJ Administrative Code that oversees home inspectors and how they should perform their job. The Standard of Practice allows inspectors to inspect a sampling of regular electric outlets but the inspector must inspect all Ground Fault Circuit Interrupt (GFCI) outlets. GFCI outlets help protect people by disconnecting the electricity if the GFCI outlet detects that the electricity is going-to-ground in a manner that is abnormal. This might occur if stray voltage and current went through a person because of faulty wiring. That’s why GFCI outlets are required outside, in garages and near all water appliances; sinks, etc. to name a few. GFCI outlets are basics in 2015 construction just like a foundation and roof.  GFCI outlets in specific areas are mandatory. So when a house is being inspected for a sale, the inspector HAS TO CHECK EVERY GFCI outlet and every outlet that should be GFCI. Without getting too technical, suffice it to say that one GFCI outlet can protect the others that it serves in a multi-outlet circuit. In this photo, the GFCI outlet on the right (the one with the buttons), operates as it should.

DSCF3587
Outlet on right is GFCI. Outlet on left is NOT GFCI protected PLUS it has reverse polarity.

However, not only is the outlet next to it NOT GFCI, it is wired backward! The polarity is reversed. Again, without getting too technical, this is very dangerous. An outlet that is wired with reversed polarity has the potential to electrocute someone very easily because the “Hot” line is in the wrong place.

3) Another blatant error on the part of the inspector that was here 6 months back is the duct for the bathroom exhaust fan. Inspectors are trained to be aware of bathroom exhaust fans that are not installed with the duct work to the outside. They sometimes vent to inside the attic (see the @regalhomeinspec Inspection find of the week from late December with the vent fan with no ductwork). While they are often very hard to find because the fans and ducts are often under insulation or in hard to reach places, in the house yesterday, it was very easy to see and right in front of you, if you looked and cared to know what you were looking at.

DSCF3637
Silver duct from bathroom fan is blowing moist exhaust air into the attic. This can promote mold growth.

Conclusion

The bottom line is that I will do the best inspection possible. Combine that with my competitive pricing and I believe I offer the best professional home inspection value in New Jersey. For a house that was “inspected” by another licensed home inspector within the past 6 or 7 months, I found items that should have been found previously.

I would appreciate your comments about this article. Please email your comments to frank07722@gmail.com

About the author. I am a NJ Licensed Home Inspector. I am the owner and Inspector at Regal Home Inspections, LLC. In addition to being a New Jersey Licensed Home Inspector I am also a NJ-DEP certified Radon Measurement Technician and Regal Home Inspections, LLC has also collected samples for lead paint, allergens and mold. We are affiliated with the best labs that perform the sample evaluation and testing. We can also help facilitate the testing of septic system and numerous aspects of oil tank evaluations. This includes oil tank integrity testing, tank locate services and soil samples. We work to ensure that the house you’re buying is sound or that you know of any issues.