Insulation R-Values Guide

Installing Insulation is a great way of lowering your heating an cooling costs while improving the comfort of your home. However shopping for insulation can quickly become overwhelming when you are confronted with so many complicated technical terms that you may not be familiar with.  one of the main technical terms associated with insulation is R-Value.

In this Guide by Insulation4US we are going to break down and explain everything you will need to know when choosing the right R-Value for your building project.

Video Guide on R-Values

What Is R-Value?

R-Value measures a materials resistance to heat. The higher the R-Value, the greater the insulation performance.

R-Value is calculating using the following formula:

R = thickness of material in metres ÷ thermal conductivity in W/mK

Example:

A  0.22m thick insulation slab with a thermal conductivity of λ=1.2W/mK has an R-Value of 0.18 m²K/W.

Structures such as walls, roofs, and floors tend to be made up of multiple different layers of materials. It is important to remember to factor in each materials individual R-Value when choosing what insulation to purchase.

R-Value Zones within the US

The Department of Energy recommends using different insulation levels based on regional climate zones to increase energy efficiency.

Locate your zone on the map and cross check it with the chart below to determine the correct R-Value for your project.

Zone #	Attic	Wall	Floor	Crawlspaces
7	R49 to R60	R13 to R21	R25 to R30	R25 to R30
6	R49 to R60	R13 to R21	R25 to R30	R25 to R30
5	R38 to R60	R13 to R21	R25 to R30	R25 to R30
4	R38 to R60	R13 to R21	R25 to R30	R25 to R30
3	R30 to R60	R13 to R21	R25	R19 to R25
2	R30 to R49	R13 to R21	R13	R13 to R19
1	R30 to R49	R13 to R21	R13	R13

R-Values Vs U-Values

We now know what R-Value is, but how does this compare to U-Value? The U-value is a measure of how much heat is lost through a given thickness of a particular material, but includes the three major ways in which heat loss occurs – conduction, convection and radiation.

R-Value = Heat Resistance = The higher the more powerful
U-Value = Heat Loss = The lower the more powerful

How to Achieve Greater R-Values In Attic Spaces

At the end of the day its a no brainer. The higher the R-value, the better the thermal performance of the insulation. To increase your R-Value simply apply an extra layer of insulation over your initial layer.

How to Achieve Greater R-Values In Exterior Walls

As mentioned above, you can always increase your R-Value simply apply an extra layer of insulation over your initial layer. However there is another way of improving thermal performance on exterior walls. You can add Insulating Sheating along with your insulation to increase your overall R-Value.

Need Additional Help?

Here at Insulation4US we are actively working to help guide all customers on their Insulation needs via the use of our Guides, Dedicated Live Chat or even by phone at 786 224 0029.
If there is anything we can do to help assist you further with your Insulation needs please do not hesitate to get in contact with us.

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