How to Choose a Rideau: Light, Privacy and Insulation

Quick answer

Choose the lining first, then the fabric, then the size. Bedrooms need a lined or blackout rideau for darkness and a little curtain insulation; living rooms usually do better with a light curtain fabric or a sheer layer that keeps daylight and daytime privacy. Measure the rod, not the window: width should be about 1.5 to 2 times the rod length, and length should run from the rod to just below the sill, to the floor, or to a slight puddle.

Most people buy a rideau because they like the colour, then discover it lets in the streetlight, the neighbour's window, or the cold. The order that actually works is duller but faster: decide what the room needs the curtain to do, then choose the lining, then the fabric weight, then the size.

This guide covers the four jobs a rideau can do — light control, privacy, insulation and decoration — and where each one should win. It also covers the measurements people most often get wrong, and how to tell whether a fabric will hang well before you commit.

Start with the job the room needs

A bedroom and a living room rarely need the same rideau. Bedrooms are judged on how dark they get and how well they hold warmth at the glass; living rooms are judged on how the light looks at 5pm. If you buy one style for the whole home, you usually end up with a bedroom that is too bright and a living room that feels shut in.

Write down three things before you shop: how dark you want the room at night, whether the window is overlooked from the street or a neighbouring building, and whether the room feels cold near the glass in winter. Those three answers point to a lining and a fabric weight far more reliably than a mood board.

• Bedroom: darkness and warmth first, decoration second.
• Living room: light quality and privacy first.
• Kitchen or bathroom: a shorter length and a fabric that tolerates humidity.

Blackout vs sheer curtains: what each one really does

Blackout and sheer are not opposites on a quality scale; they are two different jobs. A blackout lining blocks most incoming light and reduces the glow around the edges, which is what makes it useful for shift workers, light sleepers and children's rooms. A sheer rideau filters light instead of stopping it, softening the view from the street while keeping the room bright.

The most flexible setup is a double track: a sheer layer against the glass for daytime privacy, and a heavier lined rideau in front for night. If a double track is not possible, choose the layer that matches the hours you actually use the room. A sheer alone will not darken a bedroom, and a heavy blackout rideau alone will make a living room feel like a cinema at noon.

• Choose blackout when sleep, screen glare or night-shift schedules matter most.
• Choose sheer when you want daylight and only need to blur the view in.
• Choose both when the window faces a street or a close neighbour.

Curtain fabric: weight, drape and how it ages

Fabric weight decides how a rideau falls and how much it muffles sound and draughts. Lightweight cotton and linen blends move easily and suit sheer or unlined panels; heavier weaves, wool blends and lined constructions hold a straighter fold and block more light. A heavy fabric on a flimsy rod will sag in the middle within a season, so match the fabric to the hardware.

Texture matters as much as weight. A flat, tight weave reads as calm and modern and is easier to keep clean; a looser, more textured weave adds warmth but collects dust and can snag. If the window gets direct sun for hours, expect any strong colour to soften over time — that is normal, not a defect, and it is a reason to avoid committing a very saturated tone to a south-facing wall.

• Hold the fabric up to the light in the shop or check the product photos for how much passes through.
• Ask whether the panel is lined, unlined or has a separate lining layer.
• For tall windows, a heavier fabric hangs better and needs fewer panels.

Curtain size guide: measure the rod, not the window

Width is where most rideaux fail. A panel that exactly matches the window width will hang flat and look mean when closed. Aim for a total fabric width of roughly 1.5 to 2 times the rod length so the curtain keeps soft folds and still overlaps in the middle. If you want a fuller, more generous look, go closer to 2 times; if the window is narrow and the room is small, 1.5 times is enough.

For length, decide the finish line before you measure. Sill length stops just below the window ledge and suits kitchens and radiators. Floor length stops about 1 cm above the floor and is the safest choice for living rooms and bedrooms. A slight puddle, where the fabric rests on the floor, looks generous but traps dust and is impractical in busy rooms. Always measure from the rod or track, not from the top of the window frame.

• Mount the rod wider than the frame — ideally 15–20 cm beyond each side — so the curtain can clear the glass when open.
• Check the drop from the rod to your chosen finish line, then add a few centimetres for hemming.
• For radiators, stop above the radiator so heat can rise into the room.

Curtain insulation and the draught question

A rideau is not a replacement for double glazing, but a lined panel that reaches the floor and overlaps in the centre does reduce the cold feeling near a window and softens outside noise. The effect comes from trapping a layer of still air between the fabric and the glass, so a close-fitting, floor-length, lined rideau works better than a short, unlined one.

If the main problem is a draught around the frame rather than the glass itself, fix the frame first — a curtain will only mask it. If the problem is heat loss through old glass, a heavy lined rideau is a reasonable, reversible improvement, especially in rented homes where you cannot change the windows.

• Floor-length and overlapping beats short and split every time for insulation.
• A separate lining layer adds more than a coating on a thin fabric.
• Do not block a radiator; let heat into the room.

Hardware, headings and the details that change the look

The heading — the way the fabric is gathered at the top — changes the character of the rideau more than the colour does. A simple rod-pocket or tab heading reads casual; a pleated heading reads formal and uses more fabric. Eyelet headings slide easily and suit rooms where the curtain is opened and closed daily.

Check the rod's load rating before choosing a heavy fabric, and check the bracket position: brackets should sit at the ends and, on long rods, at the centre. If the room has a Suspension Songe pendant near the window, keep the rod clear of it so the two pieces do not compete or collide when the curtain is drawn.

• Match heading style to how often you open and close the curtain.
• Use a centre bracket on rods longer than about 120 cm.
• Leave clearance around light fittings and radiators.

Decision rules for buying a rideau

• Rule 1 — Lining before colour: Decide blackout, lined or sheer based on how dark and how warm the room needs to be, then choose the colour. If you cannot answer the darkness question, you are not ready to buy.
• Rule 2 — Width is 1.5 to 2 times the rod: Measure the rod length including any overhang, then multiply. Below 1.5 times, the curtain hangs flat and looks undersized. Write the number down before you shop online.
• Rule 3 — Pick the finish line first: Sill, floor or slight puddle. Measure from the rod to that line, not from the window frame. Floor length is the safest default for living rooms and bedrooms.
• Rule 4 — Match fabric weight to the rod: Heavy fabric needs a rod with a higher load rating and, on long spans, a centre bracket. A sagging rod is a hardware problem, not a fabric problem.
• Rule 5 — Layer only where it earns its place: A double track with a sheer plus a lined panel solves both daytime privacy and night-time darkness, but costs more and needs more wall space. Use a double track on street-facing windows; single layer elsewhere.

Where Maison Sarah Lavoine pieces fit

• Suspension Songe: The Suspension Songe combines rabane, cotton and brass and is available in different dimensions. If this pendant hangs near the window, plan the curtain rod and bracket positions so the rideau clears the fitting when drawn.
• Plateau Basile - Pousse de Tilleul: The Plateau Basile is a high tray with a white border following its curved edge and is available in different dimensions. A tray like this is useful for gathering curtain hooks, rings and a measuring tape while you fit a rod, and it keeps small hardware from disappearing.
• Vase Aquarius - Pousse de Tilleul: The Aquarius vase has a tubular ceramic silhouette with three glossy enamel rings around a matte white base and is available in different dimensions. A slim vase sits well on a sill or side table in front of a sheer rideau without blocking the light.

Who this guide is for

Best for

• Bedrooms that need darkness and a warmer feel near the glass
• Street-facing living rooms that need daytime privacy without losing light
• Rented homes where you cannot change the windows but can add a lined rideau

Not for

• Rooms where the main problem is a draught around the frame — fix the frame first
• Windows where you want an unlined, purely decorative panel and no light control
• Anyone who cannot fit a rod or track and needs a no-drill solution

Choose the rideau by the job it has to do, then let the colour follow. Get the width and length right, match the fabric weight to the rod, and a single well-chosen panel will do more for a room than three decorative ones.