What Is a 'Spline' and Why Is It Important?

How much do you actually know about over-window screens? Did you know that there are multiple elements that keep your home secure whilst you enjoy the fresh air and open windows? If the answer is no, then you're in the right place. At Trade Warehouse, we're in the business of ensuring that you have access to not only the best quality tools but also all the information you need when installing fly screens.

So, with that in mind, we're going to give you all the information you need about splines. This will include an in-depth analysis of their importance in the installation of over-window screens, where the spline is located and what exactly it does.

We will also answer some frequently asked questions about how splines are installed, the tools they use, how to choose the correct measurements and where you can find the perfect size spline for your screen project.

What is a spline and what does it do?

Fly screens are an important part of many households. They keep creepy crawlies out whilst giving us the benefit of open windows and fresh air. While most of us don't typically reflect on what goes into a fly screen, you may wish to know exactly what keeps these useful installations in place.

Splines are the crucial element in over window screens that fix the screen material into a screen frame. That's right, these long strips of vinyl or foam protect you from the many horrors of the outside world, like flies and debris.

So what exactly does a spline do? Well, a spline works hard to keep the screen material taut and smooth, preventing it from coming too loose and failing to protect your home whilst the windows are open. These long tubes fit into the channels surrounding the frame using specialist tools and secure the mesh material, so it stays in place for longer.

Where is a spline?

Usually, you'll find the spline on the surrounding edges of a screen frame. The spline is situated in a narrow channel that surrounds the entire frame, holding the mesh material taught over the surface area of the fly screen.

Normally, you'll be able to identify the spline by looking for a thin long, tube-like structure that is nestled into a groove that is roughly the same diameter as the spline itself. The fly screen itself is usually fitted underneath the spline, so if you locate that channel, you're likely to find the spline.

Splines can come in different materials depending on the project. At Trade Warehouse, you'll find two different types of spline- PVC rubber and DAPA foam. We use foam screening spline when the installation process requires a much more plaint material, meaning it can be easily manipulated. PVC rubber splines are super hardy against the elements and may last a lot longer.

Why is a spline important?

Overall, splines are important because they're the primary component that secures screen material in place over a window. Without a spline, it would be pretty hard to stay protected against the outside elements whilst you have your windows open.

This is because the spline installs over the mesh material and acts as a block, meaning that the material is safely secured underneath the spline and unable to move without being physically pried off with a flat blade screwdriver.

Ensuring that the spline fits is also absolutely essential to the success of your fly screen, because a spline with an incorrect diameter for the channel it fits into may impact the integrity of your screen, causing it to become damaged easily or fall off.

Frequently Asked Questions

We know how important it is that you have full clarity when installing a fly screen. To ensure that you have all the information possible, we've answered some frequently asked questions regarding splines and the installation process:

How to choose and measure the right size spline

In the event that your screen becomes damaged or you're replacing your old screen or window, you'll need to be able to choose the right size spline. Doing this requires a relatively intensive step process to ensure you gather the right measurements for the task.

This is important because the spline will need to fit inside the window or screen groove, so knowing the diameter and width is essential to proper installation. Below, we've compiled a step guide to measuring the correct spline for your installation:

1. Take the screen away from the window

Before you can do anything with the spline, you'll need to remove the frame from the window that sits behind the fly screen. These will usually be held into place with clips, so make sure you undo these before trying to pop the screen out from the frame.

2. Pry the screen spline

Once you've removed the screen and laid it down on a flat surface, you can take a flat blade screwdriver and pry the spline away from the screen. You'll know you're prying on the right material if it looks like a long strip of foam or rubber.

3. Measure the diameter of the spline

Once you have gently removed the spline from the original screen, you can use this old material to measure out for a new spline. Carefully lay your spline on a table and take a tape measure to one of the ends of the spline. Take note of the number of milimeters the diameter is as you will need this in future.

4. Measuring the spline groove

If you can't measure the diameter on the spline itself, you can do this by measuring the diameter of the groove on the actual screen. Just take a tape measure and take note of the millimeters so you can find a screen spline of the same measurements.

5. Finding a spline of the same measurements

When shopping for a new spline, it's important that you find one with the closest possible measurements for the best fit. If the measure you've taken is in between retail sizes, choose a size that the measurement is closest to by either rounding up or down.

Can I reuse the screen spline?

Yes! As long as your screen spline isn't damaged at all, you're free to reuse it on other installations. Just ensure that it is the right measurement for other fixtures as this can impact how well the screen fits into place. You should also make sure that there is nothing in the spline that may threaten the structural integrity of the screen mesh.

You may spot this if the mesh is no longer taut or begins to fall down. If your spline is too damaged for further use, don't panic. We have plenty of splines to choose from at Trade Warehouse!

Do I need tools to work with a spline?

Installing splines into the screen does require some tools in order to ensure secure installation. Known as a spline roller, this nifty little tool secures the spline into the spline channel and ensures that it has a snug fit. You can identify a spline roller by looking for a tool that resembles a pizza cutter.

This tool traditionally consists of two wheels at either end, one with a thin, flat edge and one with a grooved appearance, known as a concave wheel. Concave wheels are usually only used when installing metal screens in order to secure the screen in the channel before installing the spline.

Where can I find the perfect spline for my fly screen?

If you're stuck for places to find the perfect spline for your fly screen, why not check out Trade Warehouse. We have a full range of PVC, DAPA foam and rollers available for your fly screen installation project. With our rolls of spline, you're bound to find your perfect match!