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

Cory Cryer

We’re big talkers on the subject of energy-efficient window treatments. But that’s because we have the hard numbers to back us up. With the help of some objective research, we’ve been able to chart the energy efficiency of the most common window treatments in Houston, from drapes to blinds to shutters.

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

Everything in your house that separates the inside from the outside, from the walls to your windows, has an R-value. That value indicates how effective it is at stopping thermal energy from moving through it. A higher r-value indicates a more effective insulator.

honeycomb shades in Houston house 

Why does the R-value of a window treatment make any difference? Basically, a better insulator lets you keep your space at a comfortable temperature. Whether you want to keep in the heat during the winter or keep the heat out during the summer months, good insulation is crucial to that effort. That’s even more crucial for your windows, as they’re one of the most common culprits in heat loss throughout the entire home.

Comparing R-values & Energy Efficiency Of Window Treatments

Not every window treatment offers the same benefits, at least not in energy efficiency. Though there’s some difference based on the material and build between different companies and models, below is what you’re likely to find when comparing window treatments.

Window Covering

Average R-Value

No window treatment


Mini blinds


Pleated shades




Hardwood Shutters


Honeycomb shades


Polywood plantation shutters


R-value averages sourced from HouseLogic & Energy.gov.

A quick study of the chart shows you a number of things. The first is the fact that a few certain window coverings offer almost no benefit at all (ahem, blinds), whereas others are total workhorses in insulating. That difference in R-value might result in a difference of several degrees – that’s the difference in whether or not you turn on the AC.

Something else you might notice is that the material of your window treatment is a big deal. Honeycomb shades, which are made with multiple engineered layers designed to block heat, are able to block energy flow much more effectively than pleated shades.

plantation shutters in Houston living room 

The same way, Polywood® plantation shutters, built from a solid-body faux wood polymer, can block heat a heap better than wood shutters. That’s because natural wood can be cavernous, with natural gaps and holes that allow heat to move easily. Polywood shutters, combined with strict weatherstripping, can create a solid seal on your window when shut, which is why they have that top of the line r-value of more than 6.

Up Your Home’s R-value

The numbers don’t lie. Your window treatments play a big role in how comfortable your house can be. Think your home could be a little cozier? We can help. Talk to the team at Sunburst Shutters Houston by calling 713-853-9629, or fill out our free estimate request form below.