How to Make a Window Cornice

Your room needs… a window cornice. How about making an installing one? A window cornice is a relatively easy project that you can do yourself, no hiring required. Cornices can transform a room, giving a lackluster space a dramatic makeover. Like any other element in the interior design, you can implement whatever style you want when constructing a window cornice so it blends in with the rest of the room’s theme.

Pick a weekend for your window cornice building project and make sure you have all the tools ready to go. If you’ve done DIY projects before, you know that preparation is one of the most tedious parts, but once you’ve gathered all of the necessary tools and supplies, it’s a breeze from there.

window cornice decorated and installed


Your guiding question will be: what kind of style will your cornice have? If your home has moldings, you can certainly take inspiration from that and follow suit. If not, you can dream of any style of cornice you’d like to see above your window. Browse the different architectural styles to select the one you favor and then decide on what type of wood and finish you’ll want to apply.

It’s suggested that you select a wood type, molding, and finishes based on the design elements of your home. A cornice should tie the room together, bringing a cohesive theme and design that flows throughout the home.

Then again, you don’t have to follow whatever is already woven throughout your home; your cornice can also differ, acting as a complementary accent piece. If you have difficulty deciding, you can always buy several short lengths of different types of trim at a low cost and create several combinations before committing to one design. Mock-ups are a helpful way to avoid installing a cornice you might not like.

Dimensions are the next step for your cornice blueprint. It’s imperative that you plan out the size of the cornice in the early stages before picking up the supplies and to measure exactly according to your blueprint, otherwise you will find yourself making multiple trips to the hardware store. Account for the curtains themselves, especially when they’re bunched. You will want to ensure the ease of operation for your curtains.

Your cornice should be at least an inch or two longer than the curtain rod and deep enough to clear the finials and rings by an inch. Once you’ve settled on a design style, wood, and finish, it’s time to gather your materials.

Window Cornice Materials and Tools

To get started on your cornice-building project, you’ll want to have all these tools at your disposal. You’ll need an air powered brad nail gun, tape measure, screw gun, paintbrush, file, miter saw, drill or driver, level, sandpaper, and corner clams. You can find all these tools at any hardware store.

You may possibly have some of these tools inside your garage and it doesn’t hurt to ask your neighbor or friend. Your neighbor or friend might have some of these tools. The cost-saving strategy this year is to save money and borrowing tools from a friend or neighbor are the best way to get started on window cornice project without sacrificing a huge budget.

Just don’t forget to return all these tools to the fellow owner. Next, you’ll need these materials for your window cornice project: wood glue and filler, paint, 2 and 1/2 inch wood screws, 3/4 inch and 1-1/2 inch brad nails, wide boards for the base, crown molding and trim. Now that we have the list of tools and materials to make a window cornice, the only thing left is to get to work.

Getting to Work On Your Window Cornice

window cornices

Cut your wide boards with the miter saw, using your original measurements as a guide for their length. You’ll essentially be assembling a three-sided, lidded box. Use wood glue and nails to bind the boards together.

The brad nails and a miter saw are your friends, making the process fly by with little effort. While you can pre-drill and hand-nail most of this project, utilizing an air-powered brad nailer (which if it’s airless, you can skip the clunky compressor) will make your life much easier since a cornice project is meant to be an easy do-it-yourself project.

Next up is the trim. Your cornice project will require you to pay attention to measurements, cutting with a steady hand and marking the lengths on your cornice foundation. It’s a tedious process but if done right, you’ll only have to do it once.

Begin with the end trim piece and end with mounting the long front trim last because by doing so, you can make sure that the pieces will fit seamlessly together. If you’re a beginner in woodworking, it won’t hurt to have someone relatively experienced by your side to hold the miters while you’re measuring the lengths, marking them down and assembling the parts.

The crown molding is up next and this is the part of the process where you’ll begin to see your cornice take shape. Before, it simply resembled a three-sided wooden box and wasn’t very pretty to look at, but with the addition of the crown molding, your cornice transforms into resembling a unique architectural style.

Test-fit the crown molding pieces to check if your cut lengths are fitting together as they should. Once you have it perfect, make it final with glue and nails. A tip to keep in mind when cutting is to really utilize your pencil to make light marks when denoting your cut marks.

Quickly stenciling before you make the cut will save you from a costly mistake of having to repurchase wood and the frustration of being pushed back a step in the build process.

Using the same techniques for your crown molding, install the bottom trim to complete your cornice. Apply glue and nails as you did with the other pieces to the bottom trim. After it’s installed, you should end up with the perfect, unpainted structure of your cornice.

Finishing Your Window Cornice

There are few things you’ll need to do before you pick up that paintbrush. First, your window cornice will have a few nail holes that will require wood filler. File miters if you should feel it’s necessary for a smoother finish, especially if wood fibers can be seen in the profile of the cornice.

Sand the wood in preparation for your primer. You can use 150-grit sandpaper to do the job. Taking the time to do these final steps before painting will make your end product look professional like it just came from the factory.

Now, you can paint your window cornice. Everything looks better with at least two coats of paint atop a primer. If you chose to go with crown molding that has many grooves, juts, and crevices. A few coats of spray paint may be the best choice.

Hang Your Newly Finished Window Cornice

It’s the final step of installing your cornice. Install the ledger or cleat above the desired window (you can also paint this piece to match the wall if you’re worried it may show), screwing it into the drywall, using your level before doing so. You can also countersink pilot holes into two studs for a secure attachment, then place the wood screws.

Lifting the cornice onto the ledger may be a challenging task to do on your own, so grab a partner to help you place the cornice, lowering it onto the ledger.

All that’s left is to step back and admire your handy work. Building a cornice is not a difficult project and even those new to woodworking can tackle this do-it-yourself build in no time. The key in constructing your cornice is to have accurate measurements from the beginning and making sure you follow through with those measurements during the cutting process.

A cornice is a surefire way to bring any window to life, which in turn, can give a brand new feel to a room.

window curtains getting hanged on a window cornice

Feldco Windows

We offer durable vinyl framed, energy efficient, energy-star rated windows. Our windows are affordable because after we manufacture your windows, they’re sent straight to your home for installation. We also have built-in blinds as an option for homeowners who are looking to keep their blinds inside the glass panes instead of using curtains.

No matter what you’re looking for, Feldco has it all. Our installers are factory trained and detail oriented so you can count on us to get your windows properly installed the first time. If you need to get your windows replaced, click here and get a free quote now.

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