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The Basics About Ghosting

Ghosting

Walking into your home after a long day to see black streaks across the walls can be a horrifying scene. You may wonder if it is mold but haven’t noticed any moisture issues. These streaks may be a sign of ghosting. The term ghosting in this context doesn’t refer to supernatural hauntings or cutting off contact with another person. For this blog’s purposes, it refers to airborne particles depositing on cold surfaces such as wall studs and nails. In this blog, we will discuss ghosting and how to stop it from occurring in a property. 

What causes ghosting?

Ghosting occurs when particles in the air deposit on cold surfaces, often making patterns on the wall. Very small particles are at a size where they are influenced by air molecules. When air cools down, air molecules slow down. And when air slows down, the small particles being knocked around loose energy and are more likely to settle on a surface. This all leads to small particles depositing on cold surfaces such as wall studs and their nails. The smallest, “ultrafine” particles are often associated with combustion and outdoor air pollution. Common sources of ghosting include candles, incense, fireplaces, and wood-burning ovens. The EPA also states that burning candles with a lead core can result in lead contamination of the area. The more particles produced in the home, the worse ghosting may appear. 

Ghosting Story

While out in the field, I have seen ghosting occur both on a small scale and to the extent that it was present throughout the whole property. A client reported possible mold growth throughout the home. The black discoloration had accumulated on the wall studs and ceiling. It was also completely darkened on fan blades and even was present in the freezer. Upon further inspection, particulate matter readings were elevated for particles around 0.3 microns. The client had asked about their glass candle in the living room, which they reported was burned every once in a while. After further questioning, it was revealed that the candle was actually burned every day for the last 4 years. A surface sample concluded the discoloration was in fact soot particles. If you are interested in more horror stories like this feel free to look at our blog on the topic. 

How to Stop Ghosting

Ghosting can be stopped by preventing cold surfaces, for example by fixing the temperature difference between the exterior and interior of the property. This can be accomplished by sealing the exterior of the property and inspecting the insulation inside of the walls to make sure it is adequate.  When designing a new home, make sure there is a continuous themal plane such as rigid foam board.

An even simpler way to reduce or stop the ghosting is to remove the particulate source such as switching from combustion to electric candles and making sure wood-burning ovens or fireplaces have proper exhaust ventilation. 

In conclusion, ghosting can be a scary sight in a property, but can be avoided if the proper precautions are taken. If you think you have ghosting present in your property, who are you going to call? Not Ghostbusters, but Indoor Science!

Ian Cull

Ian Cull

Ian Cull is a nationally recognized expert in the field of indoor air quality. He is the Chief Science Officer of Indoor Science, a company he started in 2004. He speaks around the world on air quality topics and is a training provider of the Indoor Air Quality Association. Mr. Cull is a Licensed Professional Engineer (PE) and Certified Industrial Hygienist (CIH). His degree is in Environmental Engineering from the University of Illinois - Urbana Champaign. Mr. Cull has developed 50 air quality related courses for the IAQA University and is the author of the book, “Fundamentals of Mold Remediation”. In his words… “Besides being passionate about indoor air quality, I enjoy cycling, music, the Chicago Bulls, and having fun with my three kids.”