Darkened Insulation Indicates What?

It’s been said that only 20% of the U.S. housing stock is adequately insulated.

As you look at the insulation, you may see dirty or darkened insulation (see photos). That is an indication that air is leaking from the house, flowing through the insulation, and pulling dust with it. As we learned in http://www.nachi.org/energy-movement.htm, air can move through insulation, making the insulation act like a big air filter.

Adding insulation may be the best way to improve your home’s energy efficiency; however, only adding insulation may just simply increase the thickness of the “air filter.”

There are 19 common air leakage points in a typical existing home. We have a guide that provides descriptions of the areas of the home most likely to have air leakage, when those problems should be addressed, the potential durability and health concerns related to those problems, and sources for more information.

“Air Leakage and Air Sealing” guide is available at http://www.nachi.org/home-energy-inspection.htm (scroll down a little).

Join us in tonight’s free webinar (Aug. 20th, 2012). https://www3.gotomeeting.com/register/756487806

dirt being filtered by the insulation…

Wow I didn’t know that! LOL
Thanks Ben I will listen and let you know what I think.

Check out the air sealing info here:

Vented soffits and top plates are a common problem in my area.

How to inspect for darkened insulation is taught within our free, online “Home Energy Blower Door Training” video course.

When air leaks, so does the money.

You might inspect a hi-ef 90% gas furnace, and inform your client, “Great! You’ve got a very energy-efficient furnace here.”

Not so fast.

If that 90% furnace is connected to the original 25-year old ducts, which are likely neither mastic-sealed nor insulated, then effectively that 90% furnace is performing more like an old 65% pilot furnace.


Because leaking air is like losing energy. And losing energy wastes money–money your client could use to buy things they really need.