Curious About Why Your Insulation is Black? This May Be Why

If you are a long-time Windows on Washington reader, you will know we talk a lot about insulation. Why? Because good insulation is perhaps one of the most important components of an energy-efficient and comfortable home. As a quick recap, insulation works to inhibit the transfer of heat. In the winter, it prevents cold air from the outdoors from penetrating the interior of a house, helping to keep the home warmer inside. During the summer, insulation helps trap cool, conditioned air inside the home while resisting heat from the outdoors. Essentially, it helps improve the comfort of your home by maintaining a constant indoor temperature, while reducing the frequency and duration of your air conditioning unit (good for the wallet and environment!)

There are four standard types of insulation, including blanket insulation (filled with mineral fibers including rockwool and fiberglass, comes in rolled-up form); polyurethane and polyisocyanurate foam insulation (sprayed into the crevices and cavities of a home by a professional installer); loose fill insulation (consisting of cellulose, rockwool and/or fiberglass, contained in pellets or fibers and installed with pneumatic tools); and rigid insulation (typically packaged in boards or pipe fittings and is typically used to insulate wall sheaths and foundations). 

And, when it comes specifically to loose fill insulation (especially fiberglass insulation), an interesting phenomena can occur which often leaves homeowners baffled, and that is when insulation goes black. Now, how do you know if it is moldy or dirty? And what causes it to go so black? Well, the truth is both dirt and mold can attach itself to your loose fill insulation, and neither are particularly normal. Dirt on your insulation often comes from dust and dirt outside the home that does not get filtered properly, while mold is usually caused by moisture growing on your loose fill insulation. But most importantly, how do you fix the problem? Let us discuss. 

Mold Or Dirt On Your Insulation?  

While it is best left to a professional to check, you can do a check for yourself to determine if you are dealing with a dirt or mold problem. Ensuring you have all the right protective gear on (gloves, goggles and a mask), inspect your insulation. If you notice any discoloration on your insulation such as brown, black, or even pink or orange particles, you are dealing with a dirt or mold problem. Insulation sheets are a solid color, so any discoloration will be obvious. 

The good news is black insulation can be your friend, because it tells you where there are issues with your insulation. In fact, by inspecting the insulation in your attic, a home improvement contractor should be able to quite quickly find out if there are any problematic air leaks in your house (and where they are). 

Why Air Leakages Cause Insulation To Go Black 

As mentioned, loose fill insulation like fiberglass becomes discolored when it filters the air leaking from your house. While it might not be immediately noticeable, over time the air leaking from your house carries dust, other particles and moisture, which is what ultimately turns the fiberglass insulation black.

How To Fix The Problem

A home improvement contractor should be able to easily determine where the air leak is coming from, and oftentimes, it can be fixed with some quality caulk or foam to fill the air leak holes. However, sometimes if the hole is too big, you might need to cut a piece of sheet-metal or drywall to patch up the hole. An experienced insulation contractor will be able to determine the best way to fix the issue. It is a relatively simple and inexpensive task, but it will make a world of difference to the comfort, safety and energy efficiency of your home. So, if you have noticed black insulation and are concerned, call a home improvement contractor to quickly and efficiently fix it for you.