Insulating Window Covers: Blinds to Keep the Heat Out

According to Natural Resources Canada (NRCan), up to 25% of a home’s heat loss in winter occurs through its windows. During the summer months, windows are also one of the main culprits for unwanted heat gain. Without proper window insulation, your HVAC system works overtime to keep your home comfortable, leading to inflated electricity bills.

Think about those chilly mornings when stepping onto a cold floor makes you wish you had stayed under the covers a little longer.

Insulated window covers create a barrier between your home’s interior and the outside world. In winter, they help prevent warm air from escaping through the glass, while in summer, they block excessive sunlight from heating up your space. The result? A more comfortable home, lower energy bills, and reduced strain on your heating and cooling systems.

• Increased indoor comfort during cold snaps and heat waves
  
  

• Less reliance on heating/cooling systems
  
  

• Reduced energy consumption and lower greenhouse gas emissions

To understand how window coverings help with insulation, you need to understand how heat moves through a window and how covers can interrupt it:

• Conduction : Heat moves through the glazing and frame. Ever touched a cold windowpane in winter? That's conduction.

• Convection : Drafts carry conditioned air across the glass. Feel a chilly draft even when the window is shut? That's convection.

• Radiation : Sunlight becomes long‑wave heat inside the room. Notice how the sun heats up your couch even through the glass? That's radiation.

Insulated blinds and shades fight all three by trapping still air, sealing edge gaps, and reflecting or absorbing solar radiation before it reaches your furniture or thermostat.

Shopping for energy-efficient blinds? Knowing a few key numbers can save you from guessing—and regretting it later:

• R-Value : Measures thermal resistance; higher is better.
  
  

• U-Factor : Indicates how much heat escapes through a window; lower is better.
  
  

• SHGC (Solar Heat Gain Coefficient) : Shows how much solar radiation enters through the window; a lower value means better shading.
  
  

Look for window coverings that complement high-performance windows or help upgrade the energy efficiency of older ones.

Choosing the best insulated window cover depends on multiple factors, including window size, room type, moisture levels, and how the blind is mounted. Picture slashing your heating bill without compromising on comfort or style.

Cellular shades (honeycomb shades) are widely recognized for their excellent insulation properties. Their unique design traps air in hexagonal pockets, creating a thermal barrier.

Tightly fitted cellular shades can reduce winter heat loss through windows by 40 % or more . ORNL field tests show a ~25 % drop in whole‑home heating demand when cellular shades are widely adopted. In the cooling season, they can block up to 60 % of solar heat , cutting peak AC load dramatically

It’s like wrapping your windows in a cozy winter jacket, except it looks way better. Here’s a list of different cellular shade types:

• Single vs. Double Cell : Double cell shades provide two layers of insulation, significantly improving energy efficiency compared to single cell designs.
  
  

• Pleat Size : Larger pleats (¾" or more) are typically better for large windows and offer improved insulation, while smaller pleats are more suitable for compact spaces.
  
  

• Material & Lining : Look for thermal or reflective linings for enhanced performance.
  
  

• Mounting : Inside mounts look cleaner and seal better on properly framed windows. For older or drafty windows, outside mounts help minimize air leakage.
  
  

Ideal for: bedrooms, living rooms, nurseries—any space where year‑round comfort and noise absorption matter.

Make sure to clean them often so your shades can keep the heat in or block the heat better. Check out how to clean cellular shades.

Need something sleek but still tough on heat? Roller shades might just be your home's secret weapon.

Standard rollers add a modest R‑bump but excel when paired with drapery. Blackout rollers use multi‑ply fabrics that NRCan cites for  25.6 % lower conductive heat loss  compared with bare glass. Solar‑reflective & dual rollers cut glare and UV, ideal for south‑ and west‑facing condos. Outside mounts that overlap the frame by at least 2″ stop perimeter leaks essential on older wood sashes common in pre‑1990 Canadian housing stock.

Also, different types of roller shades have different insulating properties:

• Standard Roller Shades : Made of light-filtering materials, they offer modest insulation, especially when combined with curtains.
  
  

• Blackout Roller Shades : These block out more sunlight and provide improved insulation due to their thickness.
  
  

• Solar-Reflective Fabrics : These reduce heat gain by reflecting sunlight, making them ideal for sunny, south- or west-facing windows.
  
  

Consider using outside mounts on larger or older windows to ensure full coverage and better insulation.

Ideal for: kitchens, home offices, and contemporary spaces where light control and style are priorities.

Love a touch of luxury without giving up energy savings? Roman shades have you covered—literally and stylishly.

Roman shades combine style with functionality. Their thick, folded fabric creates pockets that trap air, offering moderate insulation. Opt for:

• Interlining (a hidden felt layer) for triple‑season performance.

• Thermal Lining : Opt for lined Roman shades to maximize insulation.

• Material Choices : Heavy fabrics like velvet or lined cotton enhance the energy-saving effect.

• Mounting : As with other types, outside mounts are more effective for older windows.
  
  

Ideal for: dining rooms, formal living spaces, and areas where aesthetic appeal is important.

If you’ve ever wished you could put up a shield against the cold or sun, shutters are about as close as it gets.

Shutters, especially when custom-fitted, form a hard barrier that helps insulate against both cold and heat. By forming a rigid layer, they reduce both conductive and radiant transfer. Exterior shutters, though less common in Canada,  slash cooling loads by up to 70 %  when fully closed . What to consider when shopping for shutters:

• Interior Shutters : Best for insulation when tightly fitted within the window frame.

• Exterior Shutters : Provide added protection from solar heat and cold but require professional installation.

• Material : Wood and faux wood both provide excellent thermal performance.
  
  

Ideal for: coastal properties, cottages, or any façade that can accommodate hinged panels.

Room Considerations:

• Bathrooms and Kitchens : Choose moisture-resistant materials like faux wood shutters or roller shades with mould-resistant coatings.
  
  

• Large Windows : Use shades with large pleats or layered systems for enhanced thermal control.
  
  

North- vs. South-Facing Windows : South-facing areas benefit most from solar-reflective roller shades or cellular shades with high SHGC ratings.

Window awnings can reduce solar heat gain in the summer by up to 65% on south-facing windows and 77% on west-facing windows. Similarly, well-insulated blinds and shades can reduce energy bills by 10% to 25%, depending on the type, quality, and installation method.

In provinces with colder winters and higher energy costs, the ROI can be especially appealing. You might be surprised at how quickly those small savings add up.

Let’s break it down with real numbers so you can see what’s possible.

Step 1 — Start with average household energy

Statistics Canada says the typical Canadian home used 85.4 GJ (≈ 23,700 kWh) of energy in 2021. Heating and cooling, therefore, equal roughly:

• 63.6 % (space heating) ⇒ 15,100 kWh

• 3‑5 % (space cooling, varies regionally) ⇒ 950 kWh

Step 2 — Apply window losses

If windows leak 25 % of heat , that’s 3,775 kWh of heating wasted.

Step 3 — Apply shade performance

Installing tight‑fit cellular shades that cut heat loss by 40 %  saves ≈1,510 kWh.

Step 4 — Convert to dollars

Using Ontario’s time‑of‑use winter tariffs (7.6–15.8 ¢/kWh):

• Off‑peak scenario → $115/year
  
  

• Peak‑weighted scenario → up to $240/year
  
  

Over a 10‑year shade lifespan—that’s $1,150–$2,400 —before any electricity‑rate inflation or additional summer AC savings.

Proper fit plays a big role in window insulation. Custom blinds and shades are made to fit your windows precisely, eliminating gaps where air can leak. This is especially important for older homes in Canada, where window sizes and shapes often vary. Think of it like tailoring a suit—custom fit means better performance and a much sharper look.

Inside-mount blinds are generally better for insulation, but outside-mount can be used to cover gaps or improve performance on poorly sealed windows. Custom installations also allow for layering—pairing shades with curtains or valances for enhanced insulation.

Choosing the right mount style is like picking the right winter coat—fit and function both matter.

Precise measurement (to ± ⅛″) and professional installation pay for themselves quickly by eliminating the hairline gaps that defeat bargain off‑the‑shelf shades.

A few extra tweaks can turn good insulation into great savings.

• Edge Seals & Side Channels – Stop the “chimney effect” that siphons air behind any inside‑mount shade.
  
  

• Layering – Pair a cellular shade with decorative drapery or a valance to add R‑value and cover hardware gaps.
  
  

• Motorization & Smart Scheduling – Close east‑facing shades automatically at 7 a.m. in July, open them at 9 p.m. to vent heat. Automation adds 2‑4 % extra savings in simulation studies.

Windows leak up to one‑third of a Canadian home’s heat. Upgrading to insulated window coverings is one of the easiest ways for Canadian homeowners to boost comfort, cut energy costs, and increase home efficiency year-round.

Cellular shades, roller shades, Roman shades, and custom shutters each offer strong advantages, depending on your style and needs.

• Cellular shades are the most efficient, delivering 40%+ reductions in heat loss and double‑digit bill savings, followed by roller shades, Roman shades, and shutters.

• Savings can range from 10% to 25% on annual heating and cooling bills.

• Custom-fit blinds ensure better insulation by reducing air leakage.

• Evaluate energy performance using R-Value, U-Factor, and SHGC.

• Layering and automation can take your savings even further.
  
  

Ready to take control of your home’s comfort and energy use? Explore our collection of custom insulated window covers designed for the Canadian climate.