R-Values of Shutters: Compare Energy Efficiency of Window Treatments

Neil Blackwelder

We talk a big talk when it comes to energy efficiency in window treatments. That’s because we’ve got proof for our claims. With the help of some objective research, we’ve been able to chart the energy efficiency of the most common window treatments in Charlotte, from shades to blinds to shutters.

What’s An R-Value And Why Does It Matter For Window Treatments?

Everything in your home that insulates, from the roof to your window coverings, has an R-value. That value tells you how effective it is at blocking thermal energy from moving through it. A higher r-value indicates a more effective insulator.

white shades in Charlotte house 

So what difference can the r-value of a window covering make? Well, a more energy efficient window treatment makes it easier to keep your space at your preferred temperature. No matter if you want to keep in the heat during the winter or want to stay cool in summer, you’re going to need effective insulation. That’s especially necessary for your windows, because they’re a likely culprit for energy loss in your home.

Window Treatment R-value Comparison Chart

Not every window treatment offers the same benefits, at least not in terms of energy efficiency. Though there can be some variation based on the material and construction between different companies and models, here’s what you can expect to find when comparing window treatments.

Type of Window Covering

Typical R-Value

Window alone








Hardwood Shutters


Cellular shades


Polywood plantation shutters


R-values from HouseLogic & Energy.gov.

A quick glance at the table tells you a number of things. Perhaps the first thing you notice is the fact that some window treatments offer almost no benefit whatsoever (we’re talking about you, blinds), while others are insulating powerhouses. That big gap in R-value can mean a difference of several degrees – enough to make an impact in whether you flip the switch on your AC and waste money.

You might also notice the fact that what the window treatment is made out of can have a big impact. Cellular shades, which are made with a number of engineered layers designed to block heat, are able to put a stop to heat flow a lot more effectively than pleated shades.

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The same way, Polywood® plantation shutters, made from a completely solid faux wood polymer, are able to keep out heat a to a much greater degree than natural wood shutters. That’s because natural wood can be porous, with random holes and gaps that allow heat to move easily. Polywood shutters, outfitted with seamless weatherstripping, make a solid seal on your window when shut, giving them that best in class r-value of 6 or more.

Bring Some Value Into Your Home

The stats don’t lie. Your window coverings play a big role in how comfortable your house is. Think your home could be a bit more comfortable? We can help. Talk to the team at Sunburst Shutters Charlotte by calling 980-231-1116, or fill out our free appointment request form below.