Factors to Consider When Purchasing Roof Windows

When remodeling your home or building a brand new nest for your family, you usually have plenty of available options. The same is true for choosing roof windows, which can not only make a tremendous difference to your space but also have a positive impact on your mood and comfort.

There are many types of roof windows, each with its own set of unique advantages. Naturally, you want to select those best suited to your needs.

There’s much to consider when buying a new roof window, from glazing options to the roof pitch, thermal performance, and the materials used for the window frame.

It may sound confusing, especially if you have little experience in this department, but don’t worry. To give you a head start, we’ve put together a handy guide about the factors you should keep in mind.

Let’s dive right in and explore different roof window features to help you find the right roof windows for your home.


Even though glazing is probably not the first thing that comes to your mind when thinking about roof windows, it’s one of the most important details. Whether you’re shopping for pitched roof windows or flat roof windows, paying attention to the glazing options is crucial.

That’s because the right type of glazing will allow you to enjoy the full benefits of your roof windows and help you stay comfortable inside, regardless of the weather. For example, triple-glazed windows are an excellent solution to make your home warmer during the winter.

Window glazing is the actual glass inside the window. The number of glass panes inside varies. It can be either single, double, or triple, depending on the chosen window. The more panes of glass your roof window has, the better insulated it is.

Today, windows with double glazing are the most popular on the market, primarily thanks to their energy efficiency and fair price. On the other hand, homeowners who put a lot of focus on thermal comfort and don’t mind paying a bit more out of pocket often opt for triple glazing.

Still, you shouldn’t feel discouraged from purchasing single-glazed windows. While there are better choices for people living in a cold climate, they work well everywhere else. You can, for instance, install them in a shed or garage if the sound or thermal insulation aren’t your goals.


There’s a considerable variety of options when it comes to the type of material you can use in your roof window.

  • Glass is a classic choice and the preferred material for the vast majority of roof windows. It lets in a tremendous amount of natural light, is incredibly easy to clean, and ensures excellent insulation. However, if you live in an area that’s surrounded by tall trees or often gets affected by severe weather conditions such as high winds or hail, it can break and cause lots of damage.
  • Acrylic is similar to glass, but it’s made from plastic, making it lighter and less likely to break. Thanks to its higher level of light transmittance, it lets in more natural light than glass. It will help you invite more direct sunlight into your room.
  • Polycarbonate is a naturally transparent thermoplastic. It’s hard to break or damage, making it a preferred choice for a walk-on flat roof window and flat roof windows in general. However, this material is sensitive to temperature changes and prone to scratches.


Determining the right size for your roof window is another vital element of the shopping process.

Consider the space you have available on your roof, and remember the exact purpose the particular roof window will serve.

In general, the more light you want to let in, the bigger your roof window should be. Smaller windows tend to work best in tiny lofts or dark staircases where you need to find the optimal space to place roof windows.

You also need to remember that the bigger the window’s glass area, the more heat it will let inside. A huge glazing area can be quite bothersome in lofts and attic rooms serving as bedrooms, especially during the warmest months of the year.

You can reduce the amount of heat getting inside by choosing a third inner pane in your roof windows instead of two, but it may still not be enough in particularly hot areas. Alternatively, you might invest in blinds and other accessories. For instance, integral blinds are a stylish alternative to curtains that can help you control the temperature inside your home.

You may also opt for a bigger window if your primary goal is to improve ventilation but not necessarily your home’s thermal efficiency.

An experienced professional can help you determine what roof window size will meet your needs and expectations.

Types of Roof Windows

Depending on your preferences, you can opt for either fixed roof windows or opening ones. What makes them different from one another is that fixed windows cannot be opened, while opening windows, as the name suggests, can.

A fixed window may be an excellent choice if you want to install flat roof windows in a space that doesn’t need much ventilation or can be aired out in other ways, such as a staircase or a garage. Fixed windows also tend to be sealed better and, as a result, more energy efficient, which is a significant benefit.



Conversely, if you plan to install roof windows in an attic or a dark and dingy living room, openable windows will be a perfect choice. Not only will they illuminate the room, allowing you to rely less on artificial lighting systems, but you will also have the option to keep them open for ventilation and get rid of moist air thanks to a handy latch or fastener.

Additionally, openable roof windows give you extra safety features. They can serve as a fire escape or help you leave your house in the event of a robbery. Remember that a roof window has to have an unobstructed opening area of, at the very least, 0.33 m² and a minimum height and width of 450 mm to serve as an escape route.

If you have any doubts, check with your local planning authorities prior to your specification.

At the same time, if you’re worried about people being able to access your house through a roof window, you can invest in a model with locks.

Opening Mechanisms

If you install an openable roof window, it is only natural that you want to use it to let more fresh air in and benefit from the comfort it provides. Most openable roof windows can either be opened manually or with the help of an electric mechanism.

Opening a roof window with a manual mechanism is relatively straightforward. All you need to do is stand on a stable surface or use a small stool and locate the latch. Once you pull it, you can tilt the window open and leave it this way to improve the comfort inside your room or air it out.

Electric opening roof windows are equipped with an electrically-operated chain that comes with a range of control options, from wall switches to remote control handsets. You won’t have to worry about being unable to reach your window or using a stool whenever you want to open it.

Energy Efficiency

Another crucial factor to keep in mind when purchasing roof windows is their energy efficiency. In today’s economy, the right windows can save you a fortune.

Because roof windows provide light from above, they work in a completely different way than traditional vertical windows. A single roof window may let in around three times the amount of light that a vertical window of a similar size would.

Roof windows can also make your home more energy efficient if you opt for double or triple glazing. When shopping around, pay attention to the windows with low U-value, which indicates how much heat is transferred through the window.

Thanks to a properly installed roof window with a low U-value, you will maximise daylight and won’t have to rely as much on artificial heating to keep your home warm. On top of that, you will reduce energy consumption by increasing the amount of natural light roof windows let inside.