How to Bust Those Ghostly Stains on Walls and Ceilings
Without warning, odd dark streaks called “ghosting” begin to appear on your walls or ceilings. Soon, the blemishes grow darker, forming along wall studs or ceiling rafters. Before long, a creepy outline of the building’s framing starts to appear on the sheetrock along with dark spots on the ceiling and walls.
Ghosting is the slow buildup of air-borne dust, dirt, and soot particles on walls or ceilings. Also known as “ghost stains,” “bridging,” or “thermal tracking,” ghosting creates strange patterns along exterior walls and black spots on ceilings.
Three things generally cause ghosting to form:
- Air passing through the building envelope
- High indoor humidity
- Electrostatic attraction
Inadequate insulation, gaps in the insulation or exteriors, or the absence of a thermal break allows cold winter air to penetrate inside the wall. Condensation forms, attracting interior air particles to framing and sheetrock fasteners.
What causes the attraction?
When indoor air moves— especially through interior ventilation systems— it picks up an electrical charge. The positive and negative charges force the tiny air particles to clump together.
Condensation in the walls or ceilings attracts these particles to cold spots on studs and rafters in wood framing. Light-gauge steel studs and steel drywall fasteners have a high level of electrostatic conductivity, so they too attract air particulates.
Over time, these microscopic bits of dirt and soot gather, making visible stains on walls and ceilings.
Sources of Dirt Particles
Many things contribute to poor indoor air quality:
- Burning candles (especially scented ones) or incense
- Cooking oils which smoke over high heat
- Crusty welcome mats allowing dirt to be tracked inside
- Drafts around windows, doors, and vents
- Infrequent vacuuming or dirty vacuum filters
- Pet dander
- Poorly maintained furnaces with dirty filters
- Propane logs
- Soot from woodstoves, fireplaces, and firewood
- Unvented appliances like space heaters and clothes dryers
- Unvented cook stoves
Ghost Busting Remedies
Your first response may be to simply paint over the ghosting. Don’t do it! Unless you eliminate the problem, the ghosting will return.
Finding the channels of cold air and correcting the problem can be tricky— and expensive if condensation in the walls turns out to be the culprit.
Here are a few tips on how to remedy unsightly drywall ghosting:
- Be sure gas or wood stoves are properly adjusted and vented.
- Keep the indoor relative humidity below 55% in the winter. (An inexpensive humidity gauge monitors the humidity level.)
- Replace furnace filters often.
- Seal around doors and windows to eliminate cold air drafts.
- Stop burning candles, incense, and wood-burning fireplaces
- Use bath fans to remove moist warm air outdoors.
- Use kitchen exhaust fans when cooking.
- Vent clothes dryers outdoors.
If all else fails, add insulation in the walls or ceilings where ghosting stains appear. If the building is light-gauge steel framing, try adding thermal break insulation, too.
When the problem has been resolved, clean the stained sheetrock thoroughly. Cover the ghosting marks with a stain-killing paint, and then repaint the area.
RHINO Ain’t Afraid of No Ghosting
RHINO Steel Building Systems has never received a single complaint about ghosting.
Here is why:
- RHINO’s strong commercial-grade steel framing system uses far fewer framing pieces, so there are fewer points of contact for thermal bridging.
- Our wide steel columns create deeper walls, allowing thicker insulation.
- The RHINO Pro-Value Insulation Package includes a second layer of insulation that acts as a thermal break between purlins and metal sheathing.
- RHINO’s hearty fabric vapor barrier reduces the chance of condensation forming in the walls.
- The Pro-Value Insulation Package includes hangers that keep the batt insulation in place.
Learn more about the benefits available in a RHINO steel building kit. Call us today at 940.383.9566 and speak to one of our metal building specialists for information about ghosting on walls and ceilings. Find out why so many people are hooked on RHINO steel buildings.