Steph B. -“Thank you for being so patient and thorough!”      Call us today 206-295-4330

No I am not commenting on the supernatural here, we are talking about the mysterious stains that appear inside of homes.  This “Ghosting” tells a story of poor insulation and leaky drafty homes.

Ghosts of the framing caused by thermal bridging and possible poor air quality

Tops of joists are covered with insulation this reduces heat loss

When insulating attics, is it best practice to completely cover the ceiling framing to reduce thermal bridging.  The wood conducts heat much more readily than the insulation and this makes parts of the ceilings cold in winter.

The tops of the ceiling joists have no insulation on them, they should be completely covered  with thick insulation

Indoor air pollution can cause these stains as they tend to stick to the cold surfaces in our humid heated homes.  One major contributor to these stains are candles and fireplaces.  Combustion appliances water heaters, furnaces, pilot lights that are poorly adjusted or vented incorrectly may also cause these.  Smoking, cooking grease, and dust particles all may be attracted to the cold surfaces. In most modern construction there is a central air return to the furnace.

Carpet filters air from pressurized bedroom

The air furnace blower forces air in the rooms and that same amount of air has to leave the room.  Most of it usually flows out the door and to the cold air return. If the door is closed and you have carpeting it can filter the air and leave stains.  There should be a gap under the door to allow the air to flow freely.

These stains are likely from air leaking at the wall where it meets the floor. If the house has a negative air pressure from leaky ductwork for example can cause these stains

Stains likely caused by negative air pressure in the home.





Categories: Uncategorized

JJ Greive

JJ & Suzanne are both licensed, highly skilled inspectors and educators. We are the authors of our class curriculum, and truly enjoy sharing this with our students


Leave a Reply

Avatar placeholder

Your email address will not be published.