Awnings are an excellent way to give a window, door, patio, porch, or another outdoor area a comfortable shade. The trouble is, awnings are like sails; they’re large stretches of fabric or other material that can be caught by the wind and torn away, ripped, or otherwise damaged by high winds. Thus, when you’re shopping for awnings, you want to make sure to pick one that suits your environment.
In an area with high winds, wind resistance is paramount, so you should know what to look for when you’re choosing an awning.
Let’s get started!
First of all, let’s talk about the scales used when measuring wind and wind resistance. There are, generally speaking, two scales you might see in use.
The first scale is the internationally recognised Beaufort Scale. The Beaufort Scale was developed in 1805 by Sir Francis Beaufort, on behalf of the U.K. Royal Navy. It was primarily designed to measure the waves on the sea – but it does so using wind speeds. The scale runs from 0 to 17, though levels 13-17 are not commonly used because anything above 12 is “hurricane” and, at that point, the distinction isn’t often relevant.
On this scale, 0 is a calm day with zero winds. 1 is winds between 1-5 km/h, 2 is winds from 6-11 km/h, and so on. You can see charts of these scales, as well as descriptions of how they feel and how the environment reacts, here and here.
Some awning manufacturers will talk about wind resistance in terms of the wind on this scale. Others will talk about the “class” of wind resistance.
Wind resistance class is a classification system that is much more informal than the Beaufort scale. There are four classes, zero through three.
- Class 0: The awning was either not rated, or failed to withstand sustained winds of up to 19 km/h, or Beaufort level 3.
- Class 1: The awning was tested and is designed to withstand sustained winds of up to 19 km/h, or Beaufort level 3.
- Class 2: The awning was tested and is designed to withstand sustained winds of up to 38 km/h, or Beaufort level 5.
- Class 3: The awning was tested and is designed to withstand sustained winds of up to 49 km/h, or Beaufort level 6.
Some awnings may be able to withstand much higher winds, but no formal classification exists for resistance above level 6.
If you’re not certain of the wind speeds in your area, you can check your local weather reports, or purchase a wind metre to measure the speed in the specific area where your awning will attach. Be aware that these tests and classifications are for sustained winds; gusts can be much higher and can potentially damage an awning that is not rated for it or was improperly installed.
Temporary vs Permanent Installations
Awnings typically come in two forms: temporary and permanent.
- Temporary awnings are akin to pavilions or tents. They can resist some level of wind, but need to be anchored to the ground or a structure, and thus are reliant on the strength of those anchors.
- Permanent installations are awnings that are permanently anchored to a structure, typically the side of your house or the face of your business, but occasionally to a free-standing structure such as a pergola. These tend to be more wind-resistant than temporary awnings, though they depend on the strength of their support structures, the strength of their connections, and the strength of the materials they’re made out of.
Additionally, retractable awnings are considered permanent installations for this post. Though they can retract and move, they are still permanently attached to the building or structure they’re anchored to and are thus permanent.
Fabric vs Louvres
The two primary kinds of awnings are fabric and louvre awnings. Fabric awnings are the more traditional option, a stretch of canvas, vinyl, metal, or another material.
They are solid and can be made of a variety of materials that can partially or block the light of the sun, providing different levels of shade to the area they cover.
- Fabric awnings are a more classic look but are more flexible to environmental pressures. They catch wind more like a sail, and without the proper wind-resistant design, they may be damaged by sustained winds or heavy wind gusts. More flexible fabric awnings can also accumulate rain if they aren’t angled properly, which can further damage them.
- Louvres are more like blinds. They are individual slats, made up of materials ranging from wood, glass, or aluminum. These may be fixed in place, similar to shutters. Alternatively, they may be adjustable, similar to blinds. Adjustable louvres are ideal for creating a custom environment at any time of day. Stationary louvres are good for permanent installations that need to be more comfortable but do not need to be customised throughout the day.
Louvres are typically more wind-resistant than fabric awnings, because of the gap between the slats. That gap allows wind to pass through, and will not damage the awning outside of extreme conditions. However, the dramatically different aesthetics of the two kinds of awning makes it less of a choice, because you will typically know whether you want a traditional awning or a louvre awning, and will make your choice otherwise within that category.
Awnings need a frame to stretch across, and the material that the frame is made out of is a critical component of the wind resistance of the awning. If the frame is weak, winds catching in the awning can bend or break it, and the entire awning collapses.
Most awning frames will be made of one of three materials. Wood is a traditional option but is not used as frequently these days as it used to be. Wooden frames are relatively strong and resilient and can flex somewhat with the wind, but when they fail, they snap. Wood can also degrade when exposed to the weather, much more than other materials.
The second option is steel. Steel is the strongest option, but also the heaviest and bulkiest. Steel frames can resist all but the highest winds, but may not provide the sleek appearance you desire. They can also be more expensive and more difficult to install due to their weight and bulk.
The third option is aluminum. Aluminum is a lightweight, relatively strong metal and is ideal for most awnings. It strikes the best balance between strength and sturdiness, resistance to environmental damage, and a sleek look. It is also the go-to material for most retractable awnings.
The material of the awning itself is important as well. Awnings can be made of many different materials, including mesh, canvas, cotton, polyester, acrylic, vinyl, and aluminum.
Typically, the material doesn’t matter quite as much as you might think in terms of wind resistance. Sure, a mesh will let more wind through than a canvas, which will let more air through than aluminum, but the difference is relatively negligible. What is more important is the construction of the awning, the positioning, and the strength of the frame and anchor points. Any material, catching sufficient wind, will put enough force on the frame or anchor points to break them long before the awning material itself is damaged.
The material of the awning is a more important choice for aesthetic reasons. Different colours, patterns, and appearances come from different materials. You may also have different levels of maintenance required. Aluminum or polyester awnings are typically more waterproof and longer-lasting in varied climates. Canvas, cotton, and mesh may be more susceptible to damage from the sun, rain, and blown debris.
One of the biggest points of failure for an awning under high winds are the points of attachment. The attachment to your dwelling or the structure it is attached to is critical. Bolts must be tight, anchors must be firmly attached to interior structures rather than the surface siding, and the awning itself must be firmly attached to the frame. If any of these attachment points fail, the awning will break during high winds.
For the most part, this is a matter of installation, but can also be partially dependant on the construction of the awning. If the awning does not have enough attachment points, or those points are not firmly attached to the awning itself, it can cause problems down the road.
Awnings can be flat panels, or they can have side panels for a more enclosed feel and coverage.
Side panels are aesthetically pleasing and can offer a different environment than a flat awning, but they also trap wind more easily. Luckily, side panels can often be optional in awning designs.
A Note on Retractable Awnings
Retractable awnings are an interesting point in the discussion of wind resistance.
On one hand, the flexible, hinged frame of a retractable awning is typically very weak compared to a firm, fixed frame. If a retractable awning is not retracted, it can be very weak in the face of strong winds. These multiple additional points of failure don’t even need to break completely to make the awning unusable without repair.
On the other hand, when a retractable awning is retracted, it can withstand much higher winds, far above the class rating up above. Retractable awnings can survive hurricane-force winds without damage if they are retracted in time. This, for obvious reasons, makes them a great choice for areas that have occasional high winds but are not subject to constant strong winds or recurring wind gusts.
Retractable awnings may have different designs and different mechanisms.
- Pram awnings are short, tight semicircular curves. These simply fold up and are easy to stow away as necessary.
- Folding-arm awnings have a singular hinge part of the way along with their support frames and fold in half to retract. These may need additional anchors to keep the awning material tied down once retracted.
- Accordion-style awnings retract along a linear track, and the awning material itself folds up like an accordion. They are much more wind-resistant but have creases in them that may be unsightly depending on your preferences.
- Rolling awnings are similar to roller blinds, installed horizontally. They roll up into their housing when retracted and are this completely protected from the wind, making them an excellent option. However, the housing can be larger and bulkier than other options, so it may not suit the aesthetic you’re going for.
Keep in mind, as well, that retractable awnings are typically not made of aluminum, since the stiff metal can’t be folded up or retracted easily.
Finally, you can consider the mechanism. Retractable awnings may require manual retraction or may be motorised. Manual retraction requires the use of a crank, or simply physically unlocking a joint and pulling the awning back. They are cheaper, may or may not be sturdier depending on design, but require going out and interacting with the awning even in high winds to retract it.
Motorised retractable awnings can be adjusted with the press of a button, even from inside, which makes them ideal for personal safety during a windstorm. They can also be built with a wind sensor that will automatically retract them when high winds are detected. This is the best option, but also the most expensive.
With so many options available to you, it’s easy to be overwhelmed. Wind resistance is just one of many factors, including aesthetics, construction, design, and maintenance, that you need to consider.
It’s important to recognise that no design is completely safe from failure. The strongest awnings may still fail under high, sustained winds during a tropical storm. Retractable awnings are highly wind-resistant when retracted, but they need to be retracted in time, which you may not always be able to do. These are just a few of the factors worth examining for your awning installation.
When it comes to awnings, we have a wide range of options available to you. Whether you want retractable awnings, fixed awnings, louvres, pram-style awnings, or something custom-built for your home, we have you covered. Give us a call or drop us a line today to discuss the ideal awnings for you.
Do you have any questions for us? Feel free to reach out for assistance, or leave a comment in the comments section below! We’ve helped hundreds of businesses and homeowners with professional installations and would love to hear from you.