Adding Insulation: Starting With The Attic

Adding Insulation: Starting With The Attic

So you want energy efficiency and you know you need insulation. What's next? Figuring out where to put the stuff.

A house should be properly insulated from the roof down to its foundation.

But first, for other exciting information about insulation (at least to building science nerds like me), you may want to look at:

Insulation: A Look At R-Value

Adding Insulation To A Home: How The Stuff Works

Adding Insulation To A Home: Sealing And Ventilation

This is the area most of us think about when we think insulation. Fortunately, attics are usually one of the easiest places in a house to add insulation.

WARNING!

Warning: if you have, or think you have, vermiculite insulation in the attic, don't mess around up there. Vermiculite insulation is commonly found as attic insulation in pre-1950 homesm and they may contain asbestos. In this case, if you want to add insulation to your attic, use an insulation contractor who is trained and certified in handling asbestos.

Note that all insulation contractors in the State of Michigan must be licensed -- and in addition, those handling projects like this must be certified additionally to work around asbestos.

So what does the stuff look like?

Vermiculite consists of small, lightweight pellets which create a loose-fill insulation, kind of like the peanut-type packing material used in shipping.

So, with that out of the way...

Attic Insulation

Loose-fill or batt insulation is typically installed in an attic. Loose-fill insulation is usually less expensive to install, and looks like shredded fiberglass or similar.

Batt insulation is the roll-form.

Before installing any type of insulation in your attic, follow these steps:

1. Seal air leaks. Insulation doesn't stop airflow. This means duct exhausts to the outside, cover openings, and along the tops of walls.
   
2. Insulate and seal the attic access if it is in a conditioned part of the house.
3. Make sure you know the fire-safety clearance requirements for heat-producing equipment (flues, exhaust fans, light housings), and maintain those clearances. There are some light fixtures that are IC-rated. The IC stands for insulation contact.
4. Ventilation is key. The soffit vents must not get blocked with insulation.