A very long curtain rod will frequently sag in the middle. This could, over time, result in the curtain rod ultimately breaking and requiring replacement. There is no hard and fast rule on the length of curtain rod that needs a center support, but by adding a center support to a curtain rod, you will ensure not only that the rod will hold up over time, but avoid unsightly inconsistencies in the curtain rod.
Building a center support for a curtain rod doesn't take much time, and by doing so, you can quickly fix the problem and ensure that your curtain rod stays sturdy and beautiful. Take a little trim to examine the existing supports and think about the design of the support to complement the existing supports and accommodate the size of rod you have. Here is some basin information to building your own center support for your curtain rod.
Step 1 - Design the Support
Here we will be creating a simple support with a U shaped end to hold the rod. Measure your existing rod from the outer edge of the rod to the wall. This will be how wide you will need to make the support. Then measure the width of the rod. Add one-quarter of an inch to this; this will be the width of the U cutout.
Mark your measurements on the broad side of the lumber and, from a side perspective, draw in the design and shape of the bracket you want. While this could be just about any shape, the bottom and middle of the bracket shouldn't be too thick, as you will need to be able to put screws through this and into a wall or, ideally, stud in the wall.
Step 2 - Cut Out the Design
Using the jigsaw, cut out the bracket using the drawing and lines on the wood as a guide. Go slowly and take your time. Secure your lumber to the work surface with C clamps so that the wood doesn't move during the cutting process, and you have both hands with which to guide the saw.
Step 3 - Finish the Support
Once your support is cut out, you will most likely want to put a little polish to it by giving it a good sanding. You can sand it by hand, but an electric hand sander will cut the time down significantly. Make sure to remove any ridges created by the saw, and remove any major flaws. Give it a final polish with a fine grit paper. Stain or paint the bracket so that it matches, at least somewhat, the other brackets.
Step 4 - Install the Support
Drill two holes in the bottom of the support so that screws can be driven through it into the wall. Don't make the holes too big, you still want the screws to be able to grab the wood. Locate where you want to install the brace, and screw it into the wall, preferably where a stud is. If there is no stud, use a wall anchor to give it additional support.