single pane window

There was a time when single pane windows were standard for home construction. For today’s homes though, double pane windows have replaced the single pane window in standard construction. If your home is old, however, it may still be fitted with single pane windows, which can affect your home’s energy efficiency, among other things. Let’s take a look at the pros and cons of single pane windows and discover options for controlling your home’s energy costs while maintaining its aesthetic value. 

What Is a Single Pane Window?

Much as the name suggests, a single pane or single glazed window contains only a single layer of glass, as opposed to a double or triple pane window, which contains, quite logically, either two or three layers of glass. 

How to Tell If a Window Is Double Pane

Double pane windows have been around since 1952, so there is a good chance you have them in your home. Though as construction methods and materials improve over time more recently manufactured double pane windows may have advantages over older models.

If you are not sure if you have double pane windows in your home, there are a couple of ways to make this determination. One method is to examine the inside edge of your window to look for a spacing system that separates two panes of glass. If there is not a spacing system, it is not a double pane window. The other method is to open your window so you can touch both the outside and inside of the glass in the same spot at the same time. If your fingers almost touch through the glass then in all likelihood, you have a single pane window

Double Pane Windows Vs Single Pane

Some of primary considerations when looking at a single pane window vs double pane include:

  • Energy efficiency
  • Indoor temperature control
  • Noise and soundproofing
  • Local climate

The Single Pane Window: Energy Efficiency

Can single pane windows be energy efficient? The answer to this question often reveals one of the biggest cons associated with single layer windows–their low energy efficiency rating. The energy efficiency of single pane windows is going to be inferior when compared to double or triple pane windows because the added layers provide more insulation not only around the window but in the window itself. More layers are going to provide better energy savings. 

The Single Pane Window: Indoor Temperature Control

One of the purposes of windows is to provide your home with natural light and ventilation. Over time, as heating and cooling systems have become more advanced, window construction has also needed to help control indoor temperatures, keeping them consistent. If cooled or heated air either seeps in or escapes from your home through your windows, it becomes harder to maintain a consistent indoor temperature. The insulation properties associated with double or triple glazed windows provide better indoor temperature control than a single pane window. However, if your home is not fitted with double or triple pane windows throughout, temperature control will be harder because there is still a source for air leaks. 

The Single Pane Window: Noise and Soundproofing

Just as single pane windows allow for heated or cooled air to both escape from and seep into your home, noise can act the same way. Without added insulation and soundproofing, single pane windows allow for more outside noise to penetrate into your home. 

The Single Pane Window: Local Climate

Single pane windows perform best in climates with mild, consistent temperatures. If you live in a climate that is neither too hot nor too cold, single pane windows can offer adequate insulation. However, if you live in a climate where the weather does not fall within this goldilocks zone, single pane windows can struggle to provide adequate insulation.

When it comes to a single pane window over a double or triple pane window, where you live matters.

Primary Advantages of Single Pane Windows

Up-front Costs

If looking at up-front costs, a single pane window is more cost-effective than a double pane or triple pane window. This is true for both the cost of the window itself and its installation. However, if looking at costs over time, this advantage can be edged out by the energy savings double and triple pane windows provide in the long run.

Architectural Purpose and Aesthetics

If your home is old, it may have some of that old-world charm that gives it added aesthetic value. Your windows, most likely single pane ones, can be a part of this added value. Old window glass can add aesthetic appeal to your home, especially if you are after that old-world charm. They are often custom designed or sized, sometimes even with added design elements, such as etched or stained glass. Replacing these windows can lower the aesthetic value of your home and doing so should be given due consideration. 

Maintaining Your Single Pane Windows

If you are opting to keep your single pane windows, instead of replacing them, especially those that add aesthetic benefits to your home, then giving them extra maintenance attention is important. Maintenance requirements of single pane windows can include replacing the glazing putty around the window or even the window glass itself. There are also some newer technologies that can help mitigate the drawbacks of single pane windows. This can include replacing the glass with specially designed impact glass to create single pane impact windows that are more durable and resilient. 

Single Pane Window Condensation

Deteriorating caulk around your windows, both inside and outside your home, can mean the seal around your window is compromised. This can cause excess air leaks and condensation to form on your single pane window. This added moisture can fog your windows but also, if your window frames are made of wood, can cause rotting. It is advisable to replace caulking to maintain a fresh seal. 

Repair Vs Replacement

Window repairs are often less expensive than full window replacements. Learning how to replace glass in vinyl windows as well as wooden frames or a single pane aluminum window can help keep your home maintenance costs down. 

How to Re-glaze a Window

Re-glazing a window means you are repairing old, worn or broken window glass instead of replacing the whole window pane or frame. In the process, you are also replacing the window putty and updating the seal.

  1. Start by chipping away the old window putty with a hammer and chisel
  2. Brush off and clear away any debris. 
  3. Clean the glazing rabbets and remove the glazing points that hold the glass in place.
  4. Carefully remove the old glass and replace it with a new piece measured and cut to size.
  5. Bed the new glass by adding glazing putty to the rabbets. This step helps create an airtight seal for the glass to sit. 
  6. Set your glazing points at one per side and an added extra for every foot of glass size.
  7. Clean any excess putty to form a straight line around the window. 
  8. Finally, prepare the glazing rabbets that hold the glass in place by covering with a generous coat of linseed oil and then apply a strip of new glazing putty.

If you are not comfortable with a DIY project of this kind, calling a professional to replace the glass instead of the whole window can be cost effective too. 

How to Insulate Single Pane Windows

If you live in a colder climate and want to keep heat from escaping through your single pane windows, it is a good idea to take steps to improve your window’s insulation. 

This includes:

  • Foam rubber weather sealing tape – self-adhesive tape that provides a better seal around your window to eliminate drafts
  • Insulation film – Clear adhesive film that adheres to the glass of your window to improve insulation
  • Secondary glazing – installing a second panel of glass into the existing window 

Can You Convert a Single Pane Window to Double?

It is possible to convert your single pane window to a double pane window by utilizing more recent technologies. New techniques can help mitigate the draughts and low energy efficiency that can accompany single pane windows. One technique utilizes a vacuum seal process to install a thin second layer of glass within the narrow rebate of an older, single pane window. This process can be useful when wanting to maintain the architectural aesthetics of an older home. 


What are the primary advantages of single pane windows?

In older homes, single pane windows are often custom fitted and come with architectural benefits that can lower the aesthetic value of your home if replaced.  

What are the disadvantages of single pane windows?

Single pane windows have lower energy efficiency ratings, can make temperature control in the home more difficult, especially in more extreme climates, and are less sound proof.

Are there ways to improve the insulation and energy efficiency of single pane windows?

Yes. By replacing the caulking and broken window panes on single glazed windows along with energy efficiency steps such as weather stripping and insulation film, you can cut down on drafts and heat loss in your home. It is also possible to convert single pane windows to double panes using new technologies.

If you want more information on how to make your home more energy efficient without compromising aesthetics, contact Climate Seal for a professional consultation.

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