Is It True That Thermal Curtains Work?

You’ve undoubtedly heard of thermal curtains, which help keep a room at a constant temperature. Do thermal curtains perform as advertised, blocking light and noise while keeping out draughts from windows?
Sure, thermal curtains do the trick. Even more, they perform well in both hot and cold climates. They are functionally cool by deflecting the sun’s rays and reducing the building’s inside temperature. Thermal curtains improve your home’s comfort and energy efficiency, reducing your fuel consumption and, in the long run, your utility costs.
This article has defined thermal curtains, explained how they function, provided installation instructions, and addressed whether they are effective in the summer. You will also learn how to set them up, whether they are comparable to blackout curtains, and their advantages.

How Do Thermal Curtains Work?

Thermal curtains are thickly padded to prevent cold air from seeping through windows. To increase your home’s insulation, they are constructed with many layers of materials. These drapes often include three panels; however, they might have as few as two or as many as four.

Providing thermal resistance (or R-value) and blocking thermal conductivity (or U-value) are the primary functions of thermal curtains.
Wool, silk, polyester, linen, and cotton are common materials for the attractive outer layer of a curtain, which normally faces the inside of the room.

The curtain’s thermal centre layer is often constructed from thick cotton batting, wool, flannel, or foam. The third and final layer, the backing, is a liner that blocks the sun from reaching the inside.
Fabrics, including cotton, vinyl, and reflective films, are used as backings. Thus, they serve as vapour barriers, preventing the intermediate layer from becoming moist from condensation around windows.

However, a vapour barrier may be created with the help of certain curtains, which include four layers. Since light-coloured backs reflect sunlight and heat, they are ideal for usage in the warmer months.

How to Do Thermal Drape Function?

By creating a vacuum between your window and the room, thermal curtains reduce heat loss. Insulating materials in a thermal curtain keep the warmth in during the winter and the sun off during the summer. A tight seal thus controls the airflow inside the space and reduces the heat lost through the windows.
The R-value is used to evaluate the effectiveness of insulation, with higher numbers indicating better performance. A better heat insulator is one with a greater R-value.

Open air has an R-value of zero, while attic insulation has a value of sixty. The R-value of a normal window pane is R-1 or less, whereas insulated windows have an R-value between 2 and 7, and energy-rated windows have an R-value of 3.
A wall with R-15 insulation may be placed next to a window. Since heat travels along the path of least resistance, windows serve as an entryway and exit for both incoming and outgoing thermal energy.

This means that the R-value of a window may be raised to 6 when these curtains are correctly installed.
When properly constructed, an insulating curtain may have an R-value as high as R-6.
Thermal curtains’ thick textiles do more than just insulate a room from the cold; they also muffle outside noise.

How Should Thermal Curtains Be Installed?

For thermal curtains to serve their purpose, they must be installed properly. If they are sufficiently airtight, heat loss will be prevented.
Seal the textiles’ bottom, sides, and top and position them close to the window frames before attaching thermal curtains.

They are most effective when placed on the window seal or floor and may decrease heat loss through the window by up to 19 per cent.
Installing a cornice or valance above the drapes can further reduce draughts.

Use Velcro, hooks or magnetic tape to fix the curtain to the frame or adjacent walls for the best results.

To prevent warm air from escaping via cracks, hang your drapes so they overlap generously in the Centre. Using at least two layers of curtains to regulate light and airflow will maximize the dead-air space’s thermal efficiency.

In the winter, you should keep your windows open throughout the day to take advantage of the sun’s warmth. Condensation on the windows may be lessened by simply opening the drapes.

Close your curtains to keep out as much cold air as possible when the sun goes down.
Close the drapes on sunny windows when the temperature outdoors rises or throughout the middle of the day. This reduces interior temperatures and protects contents from the sun’s fading rays.

Do Thermal Blackout Curtains Block Out Light?

No, thermal curtains do not block light and heat. Thermal curtains are often mistaken for blackout curtains because it prevents light from entering a room.
Heavy materials are used to make the majority of blackout curtains. Thin linings within the curtains do not prevent heat transmission as thermal curtains do.

Although these materials help blackout curtains block some of the sun’s rays, they still can’t compare to thermal curtains when it comes to keeping the heat out of a room. But some blackout drapes also double as thermal drapes, thanks to added insulation.

What About Thermal Blinds in the Summer?

The benefits of thermal curtains are not limited to the cooler months. White drapes (and medium to light-coloured curtains with white drapes) with thermally reflective backing reduce summer heat absorption by up to 33% by reflecting direct sunlight.
Your window’s positioning also has a major impact on its energy efficiency. The sun shines brightest into windows that face west and south and east into those that face north.
When thermal curtains work as intended, you may forego using the air conditioner and so reduce your carbon footprint.

How Do You Know Which Thermal Curtain Is Right for Me?

Here are some things to think about while searching for the finest thermal curtains:


Thermal curtains are effective because of the various fabric layers that provide insulation. Heavy cotton batting or flannel are two examples of heat-resistant fabrics that might be used to make up the intermediate layer.
For maximum effectiveness as a summertime insulator, your choice in thermal curtains should have at least two layers and blackout technology (blocks 90% of light).


A good insulating curtain should be substantial enough to cover the whole window frame. The width of an insulated curtain may range from 36 inches to 52 inches, and the length can go from 54 inches to 108 inches.
The frame size you need to fit your window depends on the style you’re going for. For a traditional appearance, install the curtain rod so it dangles 3 to 6 inches below the bottom of the window frame.

Then, extend each curtain rod three inches beyond the window’s edges.
Hang your curtains about an inch from the floor and place the pole towards the ceiling for a contemporary look. You may also let them sit on the floor to make it seem like puddles.

If you don’t want air to sneak around the corners of your blinds or shades, ensure they fit snugly within the window casing.

Velvet Silk Microfiber Cotton Polyester

Polyester and microfiber are ideal for thermal curtains because they prevent condensation from forming in the space between the window and the drapes.


It’s easy to choose thermal curtains that match your room’s style. You may hang them with sheers or other light drapes to add colour and style to your home. You can customize the style from classic to traditional to contemporary with the rod pocket, grommet top, and pleated design options.

Why are Thermal Curtains Helpful?

The benefits of thermal curtains extend beyond just keeping the heat in. The following are more advantages provided by them:

It makes your home more soundproof

Not only can thermal curtains keep the cold away, but they also muffle the sounds of the outside world.

They don’t block out all sound, but they help a lot with traffic noise. These insulated drapes also reduce loud music volume, so you may listen to them without disturbing others. Thermal curtains may reduce outside noise by as much as 10 dB inside your house.

Improves the longevity of your heating system

Having thermal curtains installed means your heating system may be turned off periodically. As a result,

you’ll extend the life of your heater.

Reduce Your Winter Energy Costs

You can stop worrying about paying high heating costs now that you have maintained your heating system.

Using thermal curtains, you can retain the heat in each room without constantly operating the heater. In addition to providing further security, thick thermal curtains help hotels save money by reducing heating and cooling costs.

Give Complete Privacy

The insulating quality of thermal curtains makes sleeping better on bright mornings possible. And since they are solid, you’ll have complete seclusion at home.

Make Your House Look New

You don’t have to face the trouble of redecorating if you just want to make your home seem better. A new set of thermal curtains is an inexpensive way to give your house a facelift without breaking the bank.

Increased Comfort

The heat lost via windows may be reduced by as much as 25% when thermal curtains are used. Insulated curtains, on the other hand, prevent moisture from condensing on your windows. Therefore, thermal curtains are a great way to add comfort and tranquillity to your house.

Choices to Meet Needs

You may get thermal curtains in various colours, materials, and styles. You may even have a custom curtain heading made.

Is There a Downside to Using Thermal Curtains?

If you want to block out the sun via your windows, thermal curtains won’t work.
Their standard lining colour is a shade between off-white and cream.
They aren’t foolproof when it comes to protecting your privacy. Even if you close your curtains at night, others can still see into your home.

How Do Thermal Blinds Work?

Lightweight and insulating thermal blinds are a smart investment for any home. Thermal blinds are a great alternative to curtains, and they come in a wide range of colours, patterns, and styles. If you like the benefits of thermal curtains, you will like thermal blinds.

Thermal Curtains

How Do You Keep Thermal Curtains in Good Condition?

How you should care for your thermal curtains depends on their design and material. Some fabrics can be washed in a machine, and thermal curtains can go straight from the washer into the dryer.

You should read the care instructions for these curtains before you throw them in the washing machine or take them to the dry cleaner.

However, reduce the dampness by opening the curtains as much as possible. Curtains may be cleaned in various ways, from spraying them with upholstery cleaning to vacuuming any leftover water.

How Should You Select Window Treatments?

Don’t use solar curtains (heat-reflective) with thermal curtains (designed to keep heat in on chilly days) to maximize your home’s energy efficiency. If you do this, the solar curtains will be able to keep the house cooler in the summer.
You should also avoid using heavy curtains made of a single piece of fabric. They are acceptable for minimal insulation needs but lack sophisticated multilayer construction. Avoid drapes with an extra layer that is poorly attached to the curtain fabric by sloppy stitching. You may, however, look for curtains that have a foam core.
If you want your drapes to cover the floor even when hung near the ceiling, you must measure your window opening before purchasing.


So, there you go! You can’t deny that there are more pros to using thermal curtains than cons, and the greatest thing is that they do what they claim to do. All that is required is that you install them to maximise the R values.
There is a wide selection of styles, colours, and patterns, so you won’t have to settle for anything you don’t like. You may have a curtain wrapped in various colours, patterns, and materials, depending on your preferences.

Get the most out of your thermal curtains by selecting a sturdy and well-made design in the appropriate size and hanging them as close to the windows as possible to create a tight seal.

Leave a Comment

Your email address will not be published. Required fields are marked *