Vertical blinds — fabric louvres hanging from a track, tilting through 180° and drawing to the side — are the default answer for patio doors, sliding doors and very wide or tall windows. Where a roller of that size would be a heavy, expensive tube and a venetian would be unliftable, verticals stay light, cheap and repairable at almost any width.

Why they persist

  • Tilt + draw. Like a venetian, you can angle louvres for privacy with daylight; like a curtain, you can pull the whole thing aside and walk through. Nothing else does both.
  • Repairability. Louvres detach individually. Dog chewed one? Sun bleached the south-facing half? You replace louvres, not the blind — and often without touching a drill.
  • Scale. Tracks span widths that defeat most other blind types, and made-to-measure pricing stays reasonable as sizes grow.

The downsides: the chains and weights at the bottom feel dated to some (weightless “chainless” louvres solve this), the louvres sway in a draught, and a drawn stack takes up 100–200 mm at one end of the track.

Measuring

General technique is in the measuring guide; verticals add a few wrinkles:

  1. Recess fit: exact recess width (smallest of three) and drop (smallest of three — louvres that brush the sill wear and stick). Retailers deduct so the louvres clear the sides and sill; check whether the quoted drop is track-top to louvre-bottom.
  2. Outside fit / patio doors: the track needs to clear the door and its handles — usually meaning generous overlap each side and a track mounted high enough for the louvres to clear the top of the frame. Decide draw direction (left, right or split) when ordering.
  3. Depth. The track itself is shallow, but tilted louvres sweep an arc of roughly their own width — 89 mm louvres need clearance from handles, radiator shelves and deep sills.

Fitting

A vertical blind track fixes either top-fix (screws up into the ceiling or top of the recess) or face-fix (brackets onto the wall). Top-fix into a solid or lintel-backed recess head is often the easiest blind installation there is; face-fix follows the same rules as any other blind (full fitting walkthrough).

The awkward cases:

  • Plasterboard ceilings under a concrete soffit (common above patio doors in flats): short screws hit concrete, long plugs need hammer drilling overhead. This is genuinely unpleasant DIY, and a fair reason to pay a fitter.
  • Very wide tracks are floppy until fixed — a second person makes a 3 m track a five-minute job instead of a wrestling match.

Once the track is up, hanging louvres, clipping in weights and connecting chains is fiddly but easy. Keep the child-safety principles in mind: the control chain needs its tensioner fixed taut to the wall (child-safe blinds).

Costs and the replace-vs-new decision

Verticals are typically the cheapest way to cover very large glass. Fitters usually price them per blind like anything else — wide patio-door tracks may attract a premium; ranges are in the cost guide.

Before replacing a tired vertical blind entirely, check whether the headrail still runs smoothly. If it does, replacement louvres in a standard width transform the blind for a fraction of the price of a new one, with zero fitting work — the best value “new blinds” purchase there is.

Frequently asked questions

Can I just replace the slats on my vertical blinds?

Usually yes. If the headrail works, most retailers sell replacement louvres cut to your drop, and standard widths (89 mm / 3.5 inch and 127 mm / 5 inch) are interchangeable across most brands. It's much cheaper than a whole new blind and there's no drilling at all.

Which way should vertical blinds draw — split, left or right?

For patio doors, match the draw to the door: if the door slides open to the left, have the blind draw right (or split) so the walkway stays clear. For windows it's mostly visual preference.

Are vertical blinds old-fashioned?

They have an office reputation, but on floor-to-ceiling glass they remain the most practical option: fabric choices have improved, they tilt like a venetian, draw like a curtain, and repair cheaply. Alternatives with a more current look — panel glides, day-and-night rollers — cost more and repair less easily.