Why Add Blackout Lining to Existing Curtains?
Blackout lining transforms ordinary curtains into powerful light blockers, improving sleep, energy efficiency, and privacy. Whether you want to darken a nursery, home theater, or bedroom, sewing a blackout lining to your existing curtains is a cost-effective DIY solution. This guide walks you through every step, from selecting fabric to finishing stitches.
Choosing the Right Blackout Lining
Types of Blackout Fabrics
- Foam-backed blackout lining – thick, heavy-duty, best for total darkness.
- Coated polyester lining – lightweight, easy to sew, good for moderate light blocking.
- Triple-weave thermal lining – adds insulation, blocks light and drafts.
Key Considerations
- Opacity rating: Look for 100% blackout if total darkness is required.
- Weight: Heavier linings may require stronger curtain rods.
- Care instructions: Most blackout linings are dry-clean or machine-washable (check label).
Tools and Materials Needed
| Item | Purpose |
|---|---|
| Blackout lining fabric | Main light-blocking layer |
| Existing curtains | Base fabric to attach lining |
| Sewing machine | For straight stitching |
| Thread (matching color) | Seam strength |
| Scissors or rotary cutter | Cutting fabric |
| Measuring tape | Accurate dimensions |
| Pins or fabric clips | Temporary hold |
| Iron and ironing board | Pressing seams |
Step-by-Step Guide: Sewing Blackout Lining to Existing Curtains
Step 1: Measure and Cut the Lining
Lay the curtain flat. Measure the width and length. For the lining, cut it 2 inches narrower than the curtain width (1 inch per side) and 4 inches shorter than the curtain length (2 inches at top and bottom). This prevents the lining from peeking out.
Step 2: Prepare the Lining Edges
Fold and press a ½-inch hem on all four sides of the lining. Stitch the hem with a straight stitch. If your lining is coated, use a longer stitch length to avoid skipped stitches.
Step 3: Position the Lining on the Curtain
Place the curtain wrong side up. Lay the lining on top, wrong side down (right sides of both fabrics facing you). Align the lining so it is centered with equal margins on sides and bottom. Pin along the top edge and side edges.
Step 4: Sew the Top Edge
Using a ½-inch seam allowance, stitch across the top of the curtain, catching both the curtain and lining. Backstitch at beginning and end. This creates a permanent attachment.
Step 5: Sew the Side Seams
Fold the lining edge under ½ inch, then topstitch close to the fold through all layers. Repeat for both sides. Alternatively, you can sew a seam ½ inch from the edge, then press the seam open.
Step 6: Finish the Bottom
The bottom of the lining should float freely to allow proper draping. Fold the bottom hem of the lining up 1 inch and stitch. Do not attach it to the curtain bottom. This prevents buckling when hanging.
Step 7: Press and Hang
Press all seams flat. Re-hang your curtains. The lining will stay hidden behind the curtain fabric, blocking light effectively.
Tips for Perfect Results
- Use a walking foot on your sewing machine to feed heavy layers evenly.
- If the curtain is very bulky, hand-baste the lining first for control.
- For grommet or tab-top curtains, attach lining separately using snap tape or hooks.
- Test light blockage by holding fabric against a bright window before finishing.
Common Mistakes to Avoid
- Cutting lining too wide – makes it visible from the front.
- Skipping hemming – raw edges fray and curtains look unfinished.
- Attaching lining at the bottom – creates tension and poor draping.
- Using wrong thread tension – puckers occur on coated fabrics.
Frequently Asked Questions
Can I sew blackout lining to sheer curtains?
Yes, but use lightweight blackout lining and consider sewing it to the top only, leaving sides free to avoid adding bulk to delicate sheers.
Is it better to sew or use iron-on tape?
Sewing provides a permanent, strong hold. Iron-on tape may fail over time, especially with heavy linings. Sewing is recommended for long-term use.
How do I clean curtains with sewn-in blackout lining?
Check the lining's care label. Many are dry-clean only. If both fabrics are machine-washable, use cold water, gentle cycle, and line dry to prevent coating damage.
Can I remove the lining later?
If you sew with a basting stitch or use a removable slip-stitch, you can unpick the lining later. For permanent attachment, use a standard straight stitch.
Conclusion
Sewing blackout lining to existing curtains is a rewarding DIY project that enhances your home's comfort and style. By following these steps and tips, you'll achieve professional-looking results without the cost of custom curtains. Remember to measure carefully, choose quality lining, and take your time with each seam. Your dark, cozy space awaits!
