Vertical blinds have a quality no other blind shares: they are built from parts that come apart on purpose. Each slat - properly called a louvre or vane - hangs individually from its own clip in the headrail, so one bleached, bent or snapped louvre does not mean a new blind. You unhook the bad one, hang a replacement, and the blind is whole again. No other common blind type lets you swap its fabric piecemeal, which makes verticals uniquely worth repairing rather than replacing.

What actually fails

Almost always, it is the soft parts, not the mechanism. Louvres fade unevenly in strong sun, snap at the top where the hanger hole is punched, or get bent and chewed at the bottom by pets, children and vacuum cleaners. The bottom weights that keep each louvre hanging straight can fall out when their pocket seam gives way, and the stabilising chains that link the weights along the bottom snap or lose their clips - the blind then swings and tangles in a draught. Occasionally a hanger clip inside the headrail cracks so one louvre will not stay up. Every one of these is a cheap, ordinary spare part; none of them is a reason to bin the blind.

Replacing a louvre, step by step

  1. Unhook the damaged louvre. Tilt the louvres open so you can reach the top of the offending one, then lift it up and off its hanger clip - most simply unhook, some need the clip flexed gently open with a thumbnail. Unclip the stabilising chain from its bottom weight first if there is one. No tools needed.
  2. Note the width. Louvres come in standard widths, and in the UK that overwhelmingly means 89 mm or 127 mm. Measure across a flat louvre to see which yours is - a replacement in the wrong width will hang in the set like a wrong-sized book on a shelf.
  3. Note the drop. Measure the full length of an undamaged louvre from top edge to bottom edge. Sellers of replacement louvres usually ask for either the louvre length or the blind drop, and they are not the same thing - check which is wanted before you order.
  4. Order the replacement, then transfer the bottom weight and chain clips from the old louvre into the new one if they are reusable - most weights just slide out of the bottom pocket and into the new one. Many replacements arrive with fresh weights anyway.
  5. Hang it. Hook the new louvre onto the clip, reconnect the chain, tilt everything closed and check it sits level with its neighbours.

Matching the fabric

Here is the honest part. If your blind's fabric range is still made, order the replacement from the same range and colour - the name is often on your original order paperwork or a label on the headrail. Even then, expect a subtle difference: the rest of the set has been fading in the sun for years and the new louvre has not, so a brand-new vane can stand out in a south-facing window no matter how exact the match. If several louvres are tired, the neat answer is a whole-set refresh: keep the existing headrail, which usually outlasts the fabric by many years, and replace all the louvres in one go. Every vane then matches perfectly, the blind looks new, and it costs far less than replacing the whole thing. If you do, order a spare louvre or two and keep them in a cupboard - your future self will thank you.

When replacement is not worth it

Two situations tip the balance towards a new blind. The first is a discontinued fabric you cannot live without matching: if the range is gone and a contrasting vane would annoy you daily, patching one louvre only postpones the decision. The second is a failing headrail - cracked carriers, a stripped tilt mechanism, louvres that no longer turn together or a cord that has given up. New fabric on a dying track is money down the drain. But if the rail runs sweetly and only the fabric has suffered, repair first: it is a ten-minute, tool-free job, and it is exactly what vertical blinds were designed for.

Frequently asked questions

Can you replace just one slat on a vertical blind?

Yes. Louvres hang individually from clips on the headrail, so a single damaged slat lifts off and a replacement hooks on in seconds, with no tools.

What width are vertical blind slats in the UK?

Almost always 89 mm or 127 mm. Measure across a flat louvre before ordering - a replacement in the wrong width will stand out immediately.

Why does my new slat look a different colour?

The rest of the set has been fading in daylight for years and the new louvre has not. Ordering the same range and colour gets you close, but in sun-facing rooms a whole-set louvre refresh is the way to a perfect match.

Is it worth repairing an old vertical blind?

If the headrail runs smoothly, yes - louvres, weights and chains are cheap spares and the track usually outlasts the fabric. If the mechanism itself is failing, put the money towards a new blind instead.