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Rick
Rick, General Contractor
Category: Home Improvement
Satisfied Customers: 18890
Experience:  Licensed construction supervisor with 35+ yrs. experience.
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I have a vaulted ceiling with attic space above it. I have

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I have a vaulted ceiling with attic space above it. I have recently noticed I can see where each of the rafters is located as dark lines are starting to form where ever the rafters are located. The attic space where this is happening has 12 in faced insulation laid between the rafters. There are vents in the roof for air circulation and the soffit vents are not obstructed. What is causing this ghosting and more importantly what can I do about it? The house is 12 years old. If I paint the ceiling with a stain blocker and the paint over it will the ghosting come back and how soon?

Rick :

Welcome, my name is XXXXX XXXXX I will do my best to help you with your issue

Rick :

Do you burn candles?

Rick :

Or have a lot of wood fires?

Customer:

no to both

Rick :

What type of heat do you have in the house?

Customer:

gas furnace high efficiency

Rick :

Well, there doesn't seem to be any of the normal sources for this type of issue which is usually caused by smoke collecting on the wall and ceiling surfaces. It shows up the outlines of the studs or ceiling joist or rafters because they are a different temperature than the surrounding insulated areas. That said you can prime this area with a shellac based stain blocking primer like Bin or Kilz. It must be the shellac based version. Then apply your top coat. This will block the stains from bleeding through. There is no way to tell when or if they will return

Customer:

Last question.

Customer:

What you are telling me is that some form of dirt or soot is in the air and the difference in temp on the surface of the ceiling space is attracting it causing the ghosting

Rick :

That is usually the cause when this type of "ghosting" shows up.

Rick :

The uniformity of the pattern eliminates other likely causes

Customer:

Thanks you just partially answered my next question but still what is say another potential cause?

Rick :

I know of no other causes for this type of issue. That's not to say no other cause exists. I've seen exactly what you describe several times in person and have heard about many other similar cases.

Customer:

Thanks for your help

Rick :

You're welcome!

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