Girl Opening Curtains
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It might not seem like a simple piece of decor could do much to make your home more livable, but a set of thermal curtains can do more than you might realize. By helping to regulate your indoor temperatures, these curtains keep you more comfortable and save you money.

Not all thermal curtains work the same, though, and how you use them also affects their performance. Knowing how these curtains do their job and following some basic guidelines will help you get the most out them.

How Thermal Curtains Work

Thermal curtains, also known as insulated curtains, work by holding heat in your home essentially the same way your winter coat holds in warmth. These curtains are made of fabric that isn’t just thicker or more insulating than the fabric used in ordinary drapes, but they’re also lined with additional layers that give them extra capabilities. Most consist of three layers:

  • Decorative layer – The fabric that faces your room.
  • Foam core – High-density foam inside the curtain’s fabric that blocks heat transfer out of the room and absorbs sound waves.
  • Vapor barrier – Non-breathable material that prevents the foam from absorbing moisture from condensation.

The curtains create a pocket of air between the curtain and the window, blocking the warmth in the room from seeping out through the window. Some thermal curtains include closures, such as Velcro strips, that let you seal them to the walls, making them even more effective.

When they’re completely closed, thermal drapes have an R-value of R-3 to R-5. That’s around the same insulation value as 1 inch of fiberglass batt insulation.

The Benefits of a Little Extra Insulation

Insulated curtains do more than protect you from chilly windows over the winter. They also reduce your need for heating, reduce stress on your heating system, and help keep your home a little more peaceful.

Greater comfort – Thermal curtains can reduce heat loss from your windows by as much as 25 percent, as well as block any chilly drafts coming from your windows, keeping your home cozier.

Lower heating bills – With thermal curtains holding the warmth in your rooms, your furnace won’t need to run as often to maintain the temperature you want. You might have noticed hotels often use heavy, insulated curtains. That’s not just because these curtains are more durable, but also because they help the business keep their energy costs down.

Less wear on your heating system – The more often your heating system runs, the more wear it sustains and debris it collects. By reducing your home’s need for heat, insulated curtains take a load off your heating system and lengthen its lifespan.

Sound insulation – In addition to blocking heat loss, thermal drapes also block noise from getting into your home. They can’t give you total silence, but they can muffle the noise of a busy road or park.

Choose Your Curtains with Care

When you shop for curtains to improve your home’s energy efficiency, don’t confuse thermal curtains, which are designed to hold in warmth on cold days, with heat-reflective or solar curtains that keep the sun’s heat out on hot summer days.

Avoid single-layer drapes that rely solely on thick fabric. These give you a little extra insulation, but they can’t compare to layered designs. Likewise, steer clear of curtains with a flimsy extra layer loosely sewn onto the curtain fabric. Instead, look for drapes with a sturdy foam core. Before you buy, measure your window and choose drapes long enough to overlap the floor even when hung near the ceiling.

How You Use Your Curtains Matters

How much comfort and savings your thermal drapes bring you depends in part on how you use them. The tighter the seal between the curtains and the wall, the more effectively they’ll perform. Hang the drapes close to the window and the ceiling. If you can’t get them close to the ceiling, mount a valance to keep the room’s heat from escaping over the top of the curtain. For even more insulating power, hang two curtains over a single window.

On sunny winter days, open your thermal curtains to take advantage of the sun’s warmth, but remember to close the curtains again when the sun goes down. Attach a closure that will let you seal the curtains tightly to the wall. Both Velcro strips and magnetic tape work well. Attach one side of the closure to the curtain and the other to the wall.

Even during darker parts of the winter, open your curtains now and then for a few hours to prevent moisture buildup on the vapor barrier, which can lead to mildew growth. You can clean your insulated curtains while they’re in place by spraying them down with upholstery cleaner and then vacuuming them. For a more thorough cleaning, have the curtains dry cleaned.

If you’ve noticed your windows feel chilly in winter or your heating bills have been looking a little high, thermal curtains give you a simple, budget-friendly way to solve the problem. To get the most out of these curtains, choose a sturdy, well-made design, size them correctly, and install them close to the window for a good seal.

Read also: What is an Air Curtain?

Editorial Contributors
avatar for Henry Parker

Henry Parker

Henry Parker is a home improvement enthusiast who loves to share his passion and expertise with others. He writes on a variety of topics, such as painting, flooring, windows, and lawn care, to help homeowners make informed decisions and achieve their desired results. Henry strives to write high quality guides and reviews that are easy to understand and practical to follow. Whether you are looking for the best electric riding lawn mower, the easiest way to remove paint from flooring, or the signs of a bad tile job, Henry has you covered with his insightful and honest articles. Henry lives in Florida with his wife and two kids, and enjoys spending his free time on DIY projects around the house. You can find some of his work on Today’s Homeowner, where he is a regular contributor.

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