How To Build Your Own Window Pergola: Tips And Design Ideas
Published November 8, 2022
Most homeowners have the desire to make their houses look as best as they can. That’s why they invest a lot of money on different parts of their house, like the flooring, roof, kitchen, bathroom, and more. Though most of these projects can indeed take your home’s aesthetics to the next level, they’re often quite expensive.
However, there are woodworking projects you can do that are simplistic and affordable, yet they can have a massive impact on your house’s aesthetics. One such project is the construction of a window pergola.
What Is A Window Pergola?
A window pergola, also known as a window trellis, is essentially a pergola hanging over the top of a window exterior frame. If you don’t know what a pergola is, it’s an outdoor structure consisting of a grid of rafters or beams that forms a roof. Four columns support the roof if the pergola is freestanding, two if it’s attached.
The main purpose of a window pergola is to, first of all, improve the house’s exterior. Its secondary purpose is to protect both the window frame and sill from debris. In the simplest terms, it’s a roof for your windows.
Unlike a regular pergola, it’s not likely that it’ll add to your home value, nor will it extend the lifespan of your windows by a lot. Its charm comes from the fact that it’s cheap and relatively easy to build, even on your own.
With that in mind, the next section will discuss what you need to know to build your own window pergola.
How To Build Your Own Window Pergola
Glossary Of Terms
Since we will be using a variety of terms you may not know, it’s best to settle that through a glossary.
- The support is the part that supports the entire structure and is the bottommost part of the window pergola. There’s a support on the left and the right of the window. A support consists of three parts:
- The back support is the piece of wood directly attached to the wall.
- The horizontal support is the part that cradles the rafters. One end is attached to the middle of the back support. It extends away from the wall, so its other end can cradle the other rafter.
- The diagonal brace is the piece of wood that connects the back and the horizontal support, and it acts as the support for the latter. One end is attached to the middle of the back support, while the other end is attached to the horizontal support.
- The rafters are the horizontal pieces of wood directly on top of the supports. For this project, there are only two rafters: one touches the wall while the other is at the outer edge of the horizontal support.
Both of the rafters stretch all the way from one support to the other.
- The top slats are the vertical pieces of wood directly on top of the rafters.
Materials You’ll Need To Build Your Own Window Pergola
- 2×6, 2×4, 2×2 lumber (the amount will vary according to the width of your windows)
- Tape measure
- 150 grit sandpaper
- 3 ½” screws
- 2 ½” screws
Tools You’ll Need To Build Your Own Window Pergola
- Safety equipment (e.g., gloves, glasses, etc.)
- Circular or miter saw
- Any drill machinery
- Drill bits
Step-By-Step Guide To Build Your Own Window Pergola
- Cut 2×6 lumber to form four pieces of 24-inch lumber.
Two of these will be back supports for the pergola, while the other two will be the horizontal supports.
You can make decorative cuts on one end of each support using a jigsaw to improve their visual appeal, but make sure the other end is flat. Smooth the surface of the supports with sandpaper.
- Assemble and lock together the back and horizontal supports.
Place the horizontal support at the topmost part of the back support. Make sure it’s aligned at the center, then drill a pilot hole behind the back support. Make sure it penetrates the horizontal support.
Once there’s a pilot hole, insert a 3 ½” screw to lock them tightly together.
- Cut 2×4 lumber to form two pieces of 22-inch lumber.
Make sure you also smooth their surfaces with sandpaper.
These two pieces of lumber will be the diagonal brace. One end will connect to the bottom center of the back support, while the other must connect to the horizontal support’s outer part, a few inches away from the edge.
- Assemble the diagonal brace to the support.
Make 45° cuts on each end so they can connect perfectly to the other two parts. Drill holes on both ends and insert 2 ½” screws on both to fit them together. The three parts must form a right triangle.
- Attach the supports to both sides of the window.
Make sure the back supports touch the window frame directly, while the horizontal support should be aligned a bit higher than the topmost part of the window frame. Once the support is in position, drill a pilot hole through the back support into the wall, then insert a 3 ½” screw to secure the support.
- Measure the distance between the two supports.
Once you have the distance, cut 2×6 lumber to form two pieces of lumber that can cover the distance between one support to the other. Make it a bit longer and not the exact length so there’s a bit of excess or overhang on both sides. These will be the two rafters. You can make decorative cuts with a jigsaw on both ends of the rafters if you want. You must also smooth their surface with sandpaper.
- Secure the rafters into the horizontal supports.
You must first place the rafters at the top of the horizontal support. Align them so the overhangs are equal on both sides. Then, drill pilot holes from the bottom of the horizontal support and into the rafters. Do this on both sides. Finally, insert 3 ½” screws on each hold to secure them together.
- Cut 2×2 lumber to make 24-inch slats.
Since the horizontal supports are 24 inches long, the top slats must also be the same length. You need to make a couple of these. The number depends on how long the rafters are. The longer the rafters, the more top slats you’ll need. As always, you can make decorative cuts on one end of the top slats, and you must smooth the surface with sandpaper.
- Secure the slats into the horizontal supports.
Place the top slats on top of the rafters in the same orientation as the horizontal supports. Each end of the top slats must be on top of a rafter. Every top slat must have a gap between one another. It’s best to have a gap of around five inches for each slat, but it depends on your preferences. It can be wider or narrower. Finally, drill pilot holes on each end of every slat, then insert 2 ½” screws into each hole.
- Apply a coat of paint or stain over the window pergola.
This step is mostly for the finishing touches. You can do what you want, but the best way to improve the pergola’s visual appeal is to apply a coat of paint over it. It’s also an excellent form of protection.
How Much Does It Take To Build A Pergola Over A Window?
Every project requires a certain amount of money to pull off, but apart from that, you must also have adequate skill and time. Otherwise, the finishing product may not turn out so well, or there may not be a finishing product at all. In that regard, here’s how much this project demands for each of these three resources:
- Skill: Compared to other woodworking projects, building a pergola over a window is relatively easy.
- Money: The cost will vary according to the length of the window pergola. After all, you have to buy more, longer pieces of lumber if it’s relatively long. But as a reference, you should expect to spend approximately $50 for every 72 inches or 6 feet of the window pergola you need to build.
- Time: You can build a pergola over a window in a single day. However, as there must be multiple windows in your house may need a couple of days to make a pergola for all of them.
If you still find it to be too much of a hassle, you can always get a window pergola kit.
A kit is basically a package that contains most of the things you need to build the structure. That includes the precut and drilled pieces of lumber. Window pergola kits don’t usually include the power tools you need.
A kit might increase the money you have to spend, but it’ll also reduce the skill and time you need to complete the project. You can get a kit for $100 to $300 if you don’t want to buy and cut the lumber yourself. But keep in mind that while pergola kits are common, window pergola kits are not. You may not find one quickly or at all.
What Kind Of Wood Is Best For A Window Pergola?
Much like most woodworking projects, the results of your window pergola construction may vary according to the materials you use. Since the project mostly involves lumber, the only decision you must make in regard to the material is what type of wood you’ll use. The best kind of wood for a window pergola tends to be pine, cedar, chestnut, maple, and oak. These types of wood are excellent as they can withstand water or moisture.
Such a characteristic is crucial since the window pergola will often get soaked whenever it rains. You can also use particle board as an alternative, but it’s typically quite difficult to work on using woodworking equipment.
The Bottom Line
Keep in mind that this is meant to be a quick guide for the most basic window pergola you can build. Since your primary goal for this project is most likely to improve your house’s visual appeal, you can make changes as you see fit. After all, preferences will vary from one person to another. Not to mention a single window pergola design can’t possibly fit every type of house, so you may need some pergola over window ideas of your own.
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About The Author
Lenard Arceo is an experienced writer who enjoys writing about home design and real estate topics. In his free time he enjoys learning to code. He has spent most of his life writing for reputable website blogs and has helped reach millions of people on the internet.