R-Values of Shutters: Comparing Energy-Efficient Window Treatments

Gary Harding

We make a big deal about energy efficiency in window treatments. But that’s because we’ve got the numbers to back up our claims. With the help of some objective research, we’ve been able to chart the energy efficiency of the most often-chosen window treatments in Denver, from shades to drapes to shutters.

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

Everything in your house that separates indoors from outdoors, from the roof to your window coverings, has an R-value. That number indicates how effective it is at preventing thermal energy from going through it. A higher r-value corresponds to a more effective insulator.

white shades in Denver home 

So what difference does the r-value of a window covering make? Simply put, a better insulator lets you keep your space at a comfortable temperature. No matter if you want to keep in the heat at wintertime or want to stay cool during the summer months, good insulation is crucial to that effort. That’s even more important for your windows, because they’re a likely reason for energy loss in your home.

Window Treatment R-value Comparison Chart

You don’t get the same benefits from every window treatment, at least not in energy efficiency. Though there can be some difference based on the material and build between different vendors and makes, below is what you’re likely to find when comparing window treatments.

Window Covering

Typical R-Value

Window alone








Wood Shutters


Cellular shades


Polywood plantation shutters


R-values from Energy.gov and HouseLogic.

A quick study of the table tells you a few things. The first is that a few certain window coverings offer almost no benefit at all (we’re talking about you, blinds), whereas others are total workhorses in insulating. That big gap in R-value could result in a difference of several degrees – enough to make an impact in whether or not you crank up your AC.

The second is that the material of your window treatment can have a big impact. Cellular shades, which are made with several insulating layers designed to block heat, are able to put a stop to heat flow much more effectively than pleated shades.

white shutters in Denver great room 

The same way, Polywood® plantation shutters, made from a solid-body faux wood compound, can repel heat a to a much greater degree than hardwood shutters. Natural wood can be cavernous, with random gaps and knots that let heat flow through them easily. Polywood shutters, outfitted with seamless weatherstripping, build a solid seal on your window when closed, which is the reason for their top of the line r-value of 6 or more.

Up Your Home’s R-value

The science doesn’t lie. Your window coverings play a big part in how comfortable your home is. Ever feel like your house could stand to be a little more comfortable? We’ll help. Talk to the team at Sunburst Shutters Denver by calling 720-538-0182, or fill out our free estimate request form below.