For my kitchen window i needed a 46 width.
Diy window cornice foam board.
How to make a cornice board valance from foam insulation 1.
To cover the boards cut a piece of batting fabric 10 wider and 10 longer than your foam box including the returns.
This cornice is 11 inches high.
Score the board with a utility knife.
Figure out the width that you want the cornice to be.
Following the directions of the foam core board tutorials i built my cornices from my foam panels.
Measure the length of your window and add a foot to that.
I used an exacto.
Determine the height of the cornice and cut the foam board accordingly.
There is no hanging fabric.
Set a straightedge across the foam board at the desired valance height.
Measure the outside width of the window including the frame or wood trim around it.
Make the corners of your cornice by.
First you need to measure the width of your window and decide how deep you need to make your cornice board and how tall you want it.
Instead a cornice is an upholstered board that is attached to the wall above your window.
Starting in the middle wrap the batting fabric toward the back as tight as possible and secure in place with nails.
Add 3 inches to each side of the measurement 6 inches total.
Measure the width of the window that the cornice will hang over.
In this way cornices provide a more structured window treatment option than valences do while also creating interest through the fabric that you use.
Add 1 5 inches and mark that.
Work your way to the ends of the box snipping and folding at the corners where necessary.
On the other hand a cornice is a hard treatment.