How to Restring a Roman Blind: A Step-by-Step Repair Guide

This practical guide walks through how to restring a Roman blind from start to finish, covering the tools needed, the step-by-step process, and tips for sourcing quality roman blind components and cord replacements.

 

Why Roman Blind Cords Need Replacing

Roman blinds are one of the most elegant window covering options available, but they rely on a cord system that is subject to wear over time.

The lift cords run througha series of rings stitched to the back of the fabric, pass over cord rollers at the top of the blind, and connect to a locking mechanism that holds the blind at the desired height. With regular daily use, these cords stretch, fray, and eventually break — usually at a point of high friction such as a cord roller or a ring that has been stitched at a slight angle.

When a cord breaks, the blind loses its ability to fold evenly, and one side will hang lower than the other or collapse entirely.

The good news is that restringing a Roman blind is a straightforward repair that most installers can complete in under an hour, and it requires only basic tools and the correct replacement roman blind components.

 

Tools and Materials You Will Need

Before starting the restringing process, gather everything you need so that the repair can be completed without interruption.

The tools required are minimal — a pair of scissors, a tape measure, a bradawl or small pointed tool for threading cord through tight spaces, and optionally a lighter or heat sealer to prevent the cut ends of synthetic cord from fraying.

The materials you will need are a length of replacement cord of the correct diameter — typically 1.0mm, 1.2mm, or 1.4mm polyester cord — plus a cord lock or cleat if the existing one is also worn, and any cord rollers that need replacing at the same time.

Always measure the total cord length required before ordering replacement parts. A simple way to calculate this is to measure the full drop of the blind, multiply by the number of cord columns, and add an extra 30 to 40 percent for the horizontal run across the top of the blind and the tail that hangs down for operation.

Materials checklist:

• Polyester lift cord — correct diameter for your blind system
• Cord lock or cleat if replacement is needed
• Replacement cord rollers if worn or damaged
• Scissors and tape measure
• Bradawl or threading tool
• Heat sealer or lighter for cord ends

 

Step 1: Remove the Blind from the Track

The first step is to take the blind down from its mounting so that you can work on it comfortably on a flat surface.

Most Roman blind tracks clip or slide into wall brackets, and the blind can be removed by pressing the release tabs on the brackets while supporting the weight of the blind with your other hand.

Lay the blind face down on a clean, flat surface — a large table or a clean floor works well — so that the cord rings and existing cord runs are visible on the back of the fabric.

Take a photograph of the existing cord routing before removing anything, as this will serve as a useful reference when threading the new cord.

 

Step 2: Remove the Old Cord

With the blind laid flat, locate the cord lock at the top of the blind and release it to free the existing cords.

Pull the old cords through the rings from the bottom of the blind upward, removing them one column at a time. If the cord has broken partway through, remove both pieces — the section below the break and any remaining cord still threaded through the upper rings and rollers.

Inspect the cord rings on the back of the fabric as you work. If any rings are loose, misaligned, or pulling away from the fabric, these should be resewn before the new cord is installed, as a faulty ring will cause the new cord to wear prematurely at that point.

Also inspect the cord rollers at the top of the blind. Rollers that show visible wear grooves or that do not spin freely should be replaced at this stage while the blind is already off the track.

 

Step 3: Cut and Prepare the New Cord

Cut the replacement cord to the correct length for each column, adding the extra allowance for the horizontal run and the operating tail as calculated earlier.

If you are using synthetic polyester cord — which is the recommended choice for roman blinds as it is non-stretch and durable — seal each cut end briefly with a lighter or heat tool to prevent fraying. This small step makes threading significantly easier and prevents the cord from catching on rings and rollers during installation.

If the roman blind components you are replacing include the cord lock, install the new lock into the track before beginning the threading process, as it is much easier to do this while the blind is still off the wall.

 

Step 4: Thread the New Cord

Starting at the bottom ring of the first cord column, tie the new cord securely to the lowest ring using a double knot.

Thread the cord upward through each ring in the column, keeping the cord snug but not tight against the fabric. At the top of the column, pass the cord through or over the cord roller and continue horizontally across the top of the blind toward the cord lock.

Repeat this process for each cord column, threading all cords through their respective rollers and bringing them together at the cord lock. The cords should all exit the lock at the same point and be gathered into a single tail that will hang down for the user to operate the blind.

Threading tips:

• Work one column at a time to avoid tangling
• Keep consistent tension across all columns as you thread
• Use a bradawl to open tight ring loops if the cord does not pass through easily
• Double-check that each cord passes over its roller correctly before moving to the next column

 

Step 5: Adjust and Rehang the Blind

With all cords threaded and secured at the lock, hold the blind up by the track and pull all the cords gently to check that the tension is even across all columns.

If one side of the blind rises faster than the other when you pull the cord, the cord in that column is too short and needs to be adjusted before fixing the tail length.

Trim all cords to the same tail length — typically 30 to 40cm below the bottom of the blind when it is fully lowered — and seal the cut ends. Reattach the blind to its wall brackets, test the full range of operation several times, and check that the blind folds evenly at each pleat as it rises.

If the blind has been correctly restrung, it should rise in even horizontal folds and hold its position at any point along the drop without slipping.

 

Sourcing Quality Roman Blind Cord and Components

The quality of the replacement cord and components used in a restringing job has a significant impact on how long the repair lasts.

Polyester cord is the preferred material for roman blinds because it does not stretch under load, maintains its diameter over time, and is resistant to UV degradation. Avoid cotton or mixed-fibre cords, which will stretch with use and cause the blind to lose its level operation relatively quickly.

When sourcing roman blind components for professional use, working with a specialist blind hardware supplier who can provide cords in the correct diameters and lengths, along with matching cord locks, rollers, and rings, will give you a reliable and consistent supply of parts for ongoing maintenance work.

Install blinds professionally by always keeping a stock of the most common cord diameters and cord lock types on hand, as these are the components most frequently needed for both new installations and repairs.

 

FAQ

How do I know what diameter cord to use when restringing a Roman blind?

The correct cord diameter depends on the size of the rings stitched to the back of the fabric and the cord rollers at the top of the blind. The most common sizes are 1.0mm, 1.2mm, and 1.4mm. If you are unsure, measure the internal diameter of the rings and choose a cord that passes through easily with a small amount of clearance.

Can I restring a Roman blind without removing it from the wall?

It is possible but not recommended. Working on a flat surface gives you much better visibility of the cord routing and makes it significantly easier to maintain even tension across all cord columns. Removing the blind for restringing will produce a better result in less time.

How long should replacement roman blind cord last?

Quality polyester cord used in a normal residential Roman blind should last several years under regular daily use. Cords that are exposed to high UV levels or that run through poorly aligned rings will wear faster. Replacing worn cord rollers at the same time as the cord will extend the life of the repair significantly.

What is the difference between roman blind cord and standard blind cord?

Roman blind lift cord is specifically designed to be non-stretch and to maintain a consistent diameter under load. Standard decorative cord or packaging string is not suitable as a substitute, as it will stretch over time and cause the blind to operate unevenly.

Where can I source roman blind components for professional repair work?

Specialist window blind hardware suppliers, including manufacturers based in Taiwan who export globally, carry a comprehensive range of roman blind components including polyester cord in multiple diameters, cord locks, cord rollers, and mounting hardware. Establishing an account with a reliable supplier will ensure consistent access to the parts needed for ongoing professional repair and installation work.