Dirt from FA system???

Mike T., Swampeast MO

Answered a strange question at Old House Journal (my only other haunt).

Black streaks appearing between attic floor boards after pad/carpet installed directly on top.

Suggested that too much return (depressurization) in the attic or too little return (overpressurization) on 2nd floor was forcing house dust--dirt and residue from coal burning--through the cracks.

Know it sounds strange, but is it possible?

Mark Hunt

Yup


but the culprit is most likely Stack effect.

I have seen this in new homes as well.

Mark H

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

Steve Ebels

Dirt from a forced air system?

> Answered a strange question at Old House Journal

> (my only other haunt).

>

> Black streaks appearing

> between attic floor boards after pad/carpet

> installed directly on top.

>

> Suggested that too

> much return (depressurization) in the attic or

> too little return (overpressurization) on 2nd

> floor was forcing house dust--dirt and residue

> from coal burning--through the cracks.

>

> Know it

> sounds strange, but is it possible?

Steve Ebels

Dirt from a forced air system?

So. Like what's new about that?

Seriously Mike. I'm not following this. How do you see streaks between the floor boards if there's carpet on top of them? Maybe it's Monday and my noggin' is still comatose from a nice restful weekend.

Mike T., Swampeast MO

Black streaks in the carpet--directly above floor board joints. Carpet (and some pads I presume) aren't air tight.

Did recommend that they pull carpet and install building or tar paper and preferably a thin underlayment as well.

These were 10" wide boards--so even if they were T&G after 100 years or so they're certain to have shunk with visible gaps--can't believe they didn't use an underlayment to begin with as the carpet will most certainly have a short life.

Mike T., Swampeast MO

Any idea of the dirt source in new structures? Just "normal" dirt? LOTS of candles?

Mark Hunt

Source


In a home we audited recently the owner complained of "stains" near the edges of the walls. This home is 4 years old.

When we performed the blower door test, we could feel air movement at the wall base. We pulled the carpeting away from the tack strip and sure enough, there was air coming through the plate.

As for the source, this lady did not burn candles at all it was just dirt. The fibres of the carpeting were acting like an air filter trapping dust and dirt.

Every hole that is drilled during construction provides a path for air currents. Warm air rising from the bottom of a structure will pick up dirt and dust on it's way out of the top of the structure. The process repeats itself minute by minute as cold air enters the bottom of the structure and is heated and begins to rise.

Candle soot stains tend to be near the ceiling or higher up on walls. That is not to say that soot from candles can not end up near the floor.

Mark H

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"