Insulation 101

Understanding Insulation

On this page, we will explain how insulation works. This is designed to help our customers learn not only the benefits of properly insulating their homes, but answer any questions you have about the process.

Proper Insulation

Reduces heat transfer from radiative heat sources
Reduces heat transfer from conductive sources
Divides the air space to reduce convection current

This combined reduction in the types of heat transfer allows you to keep your conditioned air where it belongs, regardless of the season or outdoor weather conditions. Installing your insulation correctly is the key to having it work for you instead of against you - a poor installation can result in a loss of 25-30% of your R-value. Combining insulation with other R-value rated products increases what they call your Effective R-value, and can help you increase your heat retention benefits.

Primary Home Improvements

How Insulation Works

R-value and Heat Transfer are the two main factors that determine how ell a specific type of insulation can resist heat flow. Your HVAC system must replace the heat gained in the summer and the heat lost in the winter to keep your space comfortable. Heat resistance is created by properly insulating a space, which reduces heat flow and allows your space to maintain a comfortable, even temperature.

Insulation 101

What is R-Value?

The ability of a material to resist temperature changes can be measured by its R-value, just as we can measure the level of energy (heat) in an object by determining its temperature. Thermal Resistance is the source of the term. Commercial insulating materials such as cellulose, fiberglass, and spray foam are tested and given an R-value rating that indicates how well they keep heat out. The better the material insulates, the higher the R-value.

R-value is a measure of thermal resistance per inch that can be used to compare materials “apples to apples.” A one-inch cube of R-7 material will be twice as effective as a one-inch cube of R-3.5 material at insulating. A material with a high R-value can add up quickly. For example, a six-inch thick layer of R-4 material would be rated R-24.

The R-value of a buildings insulation is important, but doubling the R-value won’t double its resistance to heat loss or gain. Doors, windows, studs, and air leakage are among the complicating factors. Temperature change occurs through the conduction in studs, windows, doors, and other building elements, as well as through air movement, regardless of the R-value rating of your insulation. The R-value is only one part of the overall picture.

Insulation 101

Heat Transfer. Why is that important?

Heat transfer is the great balancing act of energy. It all comes down to nature's tendency to balance and normalize different energy levels.

When it comes to heat loss in our homes, there are a few basic rules to follow:

Heat flows from hot to cold
It can never be stopped, only slowed
It can flow by convection, conduction, or radiation
Insulation prevents heat loss by resisting heat flow, as measured by R-Value

A difference in air temperature is the primary cause of heat transfer. Convection, conduction, and radiation are the three methods by which heat is transferred from your home to the outside.

The natural movement of air caused by temperature differences is referred to as convection. You’ve probably notices that the upper level of your home is warmer than the lower level during the winter or summer as heat rises.