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Add instant style to your home’s exterior with these simple DIY cedar window boxes! Let me show you how to make easy window boxes for under $15 and in just a few hours.
It’s time for another DIY challenge with some of my favorite DIY bloggers! This month’s challenge? An outdoor DIY project!
A bunch of us have teamed up to share with you some fun, DIY projects to make for your outdoor spaces. Be sure to scroll to the bottom to check out everyone else’s tutorials!
For my project in this outdoor DIY challenge, I’m going to teach you how to make cedar window boxes.
We recently added a cedar window box to the front of our she-shed and I’m seriously in love with it. It’s amazing what a bit of greenery and flowers can do for a space!
Not only are these easy window boxes a super simple woodworking project, but they are the perfect way to increase your home’s curb appeal for cheap!
Our box only cost about $15 (for a 42″ window) and I was really impressed with how much prettier the front of the shed looked after adding a such a basic cedar window planter box to it!
Well, let’s get to it, shall we?
Please note: Some of the links in this post are affiliate links, which allows me to make a small commission from your purchase, but your purchase price stays the same. Thank you for helping support my blog! I greatly appreciate it!
DIY Cedar Window Boxes Tutorial
For a printable copy of the materials and instructions, scroll down.
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How to Make Window Boxes
Begin by measuring the width of your window.
We chose to install ours underneath the bottom window trim, so we made the box as wide as that piece of trim.
Next, use your cop saw to cut three of your cedar fence boards to that length.
Then, use your table saw to rip one of those boards down by 1″ for the bottom.
After the front, bottom and back pieces are cut, it’s time to cut your two side pieces and middle support.
Begin by measuring and marking a piece that is the width of your board at the top and that width minus 1″ on the bottom. This will give the the front of the box a slight taper.
Then, while keeping your board flat against the guide on your chop saw, rotate your saw’s blade until the straight edge of the hole lines up with your cut mark.
Cut the first piece, then keep the angle the same and use it as a template for the other two in terms of length.
Two of those pieces are your sides, the other is your middle support.
For the middle support, cut .5″ off the bottom (narrower end) to account for the bottom of your box and then 2″ off the top (wider end) to keep it underneath the top of the dirt.
Now that you have all your pieces cut, it’s time to assemble!
Begin by gluing and nailing your sides into the back (with the back covering the end of the side.)
Then install the front the same way.
Once the main box is built, push your bottom piece in from the top and nail it in on all four sides with about 4″ between nails all the way around.
Next, install the middle support. Place it in the middle of the box and nail it in from the front, back and bottom.
The last part of the assembly is building and installing the top trim.
Begin by using your table saw to rip down one cedar board into two 1.5″ side strips.
Then, measure the width of and depth of the box you built.
Cut 2 pieces out of those 1.5″ strips at the width plus .5″ and 2 strips at the length plus .5″ (both with mitered ends and the dimension as your LONG side.)
Work your way around the box installing the mitered pieces as a frame on the top with 1/4″ overhang.
Be sure to nail them into the box from the top and into each other from the sides.
Now it’s time to install the box on your house!
Using a drill and construction screws, screw the box into the siding where there is a stud (typically along the edge and center of the window.)
For water drainage, use a drill with a 1/4″ drill bit to drill holes along the bottom.
Now it’s time to fill the box!
Begin by lining the box with plastic. We just used a plastic drop cloth from the painting section. This keeps the wood from getting soggy and damaged by the soil and water.
Don’t forget to punch holes in the plastic in line with the holes in your box.
Then, line the bottom with a bit of gravel (to prevent the water holes from filling up) and fill the box half-way with potting soil.
Line your flowers up underneath the window to get a feel for how it will look and once you’re happy, plant them in the box!
And that’s it! Now you have a lovely DIY window box!
I love how ours looks on the front of the she-shed. 🙂
I wonder what Chris would say if I told him I wanted cedar window planters on the house too? 😉
In case you’re curious about the flowers we chose, we planted Big Falls White Bacopa, Yellow Violas, White Impatiens, and Vinca Vine. The front of our shed is almost full shade, so we chose some annuals and some perennials, all of which enjoy shade.
I hope this simple tutorial for building a DIY cedar window planter box helps you add some fixer upper window boxes to your home!
Here are the printable instructions:
- Cut 3 cedar boards to the width of your window.
- Rip 1" off of one of those boards for the bottom.
- Measure and mark another cedar board end for your side piece with the width of your board at the top and the width minus 1" at the bottom Cut 3 of those.
- Trim one of those into the support by cutting 1" off the bottom (narrow side) and 2" off the top (wider side.)
- Glue and nail the back into the sides and then the front into the sides.
- Push the bottom into the box and nail in from all sides with nails spaced at 4" all the way around.
- Glue and nail in the middle support.
- Rip another cedar board into two strips each 1.5" wide.
- Use those strips to build a mitered frame for the top with 1/4" overhang and install one piece at a time nailing into the box and into each other.
- Screw the box into the house's siding and studs under the window trim with construction screws.
- Drill holes along the bottom for water drainage.
- Line with plastic, add gravel and potting soil, and plant your flowers!
Also, don’t forget to check out all these other fantastic DIY outdoor projects from my blogging buddies:
Let me know if you have any questions!