• 600 S. Vincent Ave. Azusa, CA 91702
Proudly Serving All of California (800) 707-9278

Insulation Terms to Know: K-Value, C-Value & U-Value

If you’ve read our blog, you know we’ve written about the R-value of insulation, which basically represents how effective an insulation material is. But did you know there are more variables than just R-value? Related terms are K-value, C-value and U-value.

A lot of insulation terms that may be confusing, but insulation installation shouldn’t be a DIY project. Asking insulation contractors or professionals is always your best option, but knowing some basics before talking to the pros can be helpful!

K-Value, C-Value & U-Value

Insulation K-value, or K-factor, is used to rate the material’s ability to allow heat to pass through it, independent of its thickness. The lower the K-value, the better the insulator.

Insulation C-value, or C-factor, is used to rate thermal conductance; it’s the number of BTU (British thermal units) that pass through a square foot of material with a 1-degree temperature difference for a specified thickness. The lower the C-value, the more effective the insulation.

Insulation U-value is known as thermal transmittance, which refers to the heat transmission through an area of a material construction, induced by temperature differences between the adjacent environments. The lower the U-value, the better.

It can be tough to put insulation terms like these into layman’s terms, but what you basically need to know when it comes to insulation U-value, K-value and C-value is that:

  • A lower U-value (which can kind of be thought of as temperature difference between adjacent areas) indicates more effective insulation.
  • A lower C-value means the insulation performs better—and the same thing with a higher R-value.
  • The lower the K-value, the greater the insulating value for a particular thickness and given set of conditions.

How Effective Are Different Types of Insulation?

In addition to the U-value, K-value and C-value, the type of insulation you use can determine its effectiveness, depending on what your goals are. For example,

  • Loose-fill cellulose and fiberglass insulation are the best at soundproofing.
  • Spray foam insulation is very effective at reducing air infiltration.
  • Radiant barrier helps your home stay cool in the summer, by reflecting heat from the sun and is especially cost-effective in warm climates (like here in California).

To learn more, contact the expert insulation contractors at OJ Insulation!

Where should you insulate in your home? Check out our interactive infographic:

Home Insulation

We insulate attics, walls and crawl spaces.

Commercial Insulation

We insulate warehouses, offices, studio spaces & more.

Insulation Removal

Do you need to remove old insulation? We can help.

Fireplaces & Mantels

We work with builders to install fireplaces and mantels.

Are You Sure?
You are about to leave OJ Insulation and enter a third-party site. OJ Insulation and Installed Building Products have no control over, and accept no liability, obligation, or responsibility for, the contents or performance of other websites. Any such link does not constitute an endorsement or any representation regarding, the linked website, its content, its owner, its performance, its owner’s products or services, or any forward-looking statements found in.
Leave Page