What do you do if you find the perfect curtains, but they're so thin and sheer that the sun shines right through? In the light of day, this could put a glare on the TV, cause the inside temperature to rise, or ruin a midday nap. What you need is blackout curtain lining. This heavy-duty liner is hidden behind the pretty curtain but works hard to block sunlight from shining through. Save money by making your own following our step-by-step instructions below.
Make sure the curtains are wider and longer than what you want your finished curtains to be. There needs to be room for seam allowances on the sides and enough fabric to fold the top down to create a casing and hem the bottom. Your curtain fabric needs to be wider (ideally 4 inches, but you can make do with a little less) than your blackout lining. If your blackout lining is too wide, just cut it down.
Iron the curtain panel and lay it on the floor, right side up.
Cut your blackout fabric so there will be 2-inch border on the sides of the curtain panel when it is laid on top of the panel.
Lay blackout fabric on top of curtain panel with right side down so the right sides of both materials are together. Center the blackout fabric on the curtain panel. Line up the side edges of the blackout fabric and curtain panel, and pin them together. Push the extra fabric to the center.
Sew the sides together with a 5/8-inch seam allowance, which should put the seam just inside the original curtain's side hem. When you flip the the curtain right side out, the original stitching will be hidden.
Iron the seams open. Make sure to place a barrier cloth like a pillowcase or towel between the iron and the blackout material because it doesn't tolerate heat well. Then turn the curtain right side out and iron sides of curtain if needed.
Make the casing for the rod by folding the top over 5 inches; mark line at 3 inches from top. Sew a straight line across the top on both of those lines.
Hem curtains if needed by cutting off extra length, then folding up raw edge once and then once more; pin. Then sew a straight line across the fold to finish.