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

Curtis Orton

We’re big talkers when it comes to energy efficiency in window treatments. But that’s because we’ve got the hard data to back us up. With the help of some outside research, we’ve been able to directly compare the energy efficiency of the most often-chosen window coverings in San Jose, from shades to drapes to shutters.

What Is R-Value And Why Does It Matter For Window Coverings?

Everything in your home that contributes to insulation, from the walls to your window coverings, has an R-value. That value lets you know how effective it is at blocking thermal energy from moving through it. A larger r-value indicates a more effective insulator.

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Why does the R-value of a window covering matter? Simply put, a more effective insulator lets you keep your house at your preferred temperature. No matter if you want to keep the heat inside at wintertime or keep your home cool during the summer months, great insulation is a requirement. That’s even more important for your windows, as they’re one of the biggest areas of heat loss throughout the whole home.

Window Treatment R-value Comparison Chart

Not every window treatment offers the same benefits, at least not when it comes to energy efficiency. Though there can be some variation based on the material and construction between different manufacturers and makes, below is what you’re likely to find when comparing window coverings.

Type of Window Covering

Average R-Value

No window treatment


Mini blinds






Wood Shutters


Honeycomb shades


Polywood plantation shutters


R-values from HouseLogic & Energy.gov.

A quick look at the chart shows you a few things. Perhaps the first thing you notice is the fact that a few certain window treatments offer almost no benefit at all (we’re talking about you, blinds), whereas others are energy-efficient beasts. That big gap in R-value might mean a difference of several degrees – enough to make an impact in whether you dial up your AC and waste money.

Something else you might notice is that what the window treatment is made out of can have a big impact. Honeycomb shades, designed with multiple engineered layers designed to block heat, can block energy flow much more effectively than pleated shades.

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The same way, Polywood® plantation shutters, made from a solid-body faux wood compound, can block heat a lot more effectively than natural wood shutters. Natural wood can be porous, with random gaps and holes that allow heat to move easily. Polywood shutters, combined with custom weatherstripping, build a solid seal on your window when shut, which is the reason for their 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’ll help. Talk to the team at Sunburst Shutters San Jose by calling 916-542-1305, or fill out our free consultation request form below.