Hung correctly they make a window look larger, keep heat in through a six-month heating season and soften a hard room. Hung as most people hang them, they do none of those things.
The hanging height, which is the whole decision
Curtains hung inside the window reveal permanently cover glass, because they have nowhere to go when open. Hung outside and above the reveal, they clear the opening entirely and the window reads as larger.
The rule that produces the best proportion is to fix the pole close to the ceiling rather than just above the window, and to extend it beyond the reveal on each side by enough that the gathered fabric sits on wall rather than on glass. In most rooms that is 20 to 30 cm each side.
The gain is not decorative. In a country where the sun sets before half past four in late December and a large share of winter days are overcast, the difference in usable daylight over five months is real.
Length
To the floor, or within a centimetre of it. Curtains stopping at the sill cut a room horizontally and make the ceiling look lower, which in Luxembourg's 1970s stock with modest ceiling heights is the opposite of what is needed.
Where a radiator sits under the window, which is common, curtains reaching the floor over it block the heat during the heating season running roughly October to April. Two workable answers: hang them to just above the radiator with the pole still near the ceiling, or move the seating rather than shortening the fall.
Deep reveals, which older buildings have
Converted townhouses in Limpertsberg, Belair and the Gare district frequently have deep window reveals. They are handsome and they cut the angle of light entering the room.
Hanging outside the reveal partly compensates for that, which is a further argument for it in exactly the stock where people most often hang inside because the reveal looks like the natural place.
What fabric does through a Luxembourg winter
Heavy lined curtains reduce heat loss through glass measurably, and in older buildings with single glazing on a rear elevation, which is common in converted stock, that is a genuine saving across a heating season.
They also add mass to the largest hard surface in most rooms, which reduces reverberation. That matters for conversation, for television and for anyone taking a call, and in a building with timber floors it contributes to reducing what carries to the neighbours below.
Where the room overheats in summer, curtains help less than people expect. Internal fabric stops glare after the energy has passed the glass; external roller shutters stop heat before it enters. You cannot add external shading yourself, since the facade is almost always a common part of the copropriété.
Privacy at street level
In the denser districts, ground and first-floor rooms face the street directly. The usual solution is two layers: a sheer that admits light while obscuring the interior during the day, and a heavier curtain for the evening.
A sheer costs some daylight, which matters here. Where the room is already dark, a better answer is frequently a lower sheer covering only the portion of the window at eye level from the pavement, leaving the upper glass clear.
Fixing, and what needs permission
A pole near the ceiling requires fixing into the wall or the ceiling. In a rental, read the lease and photograph the wall before and after: filling and touching in a fixing costs a few euros before an exit inspection and appears at contractor rates afterwards.
In an owned apartment, anything touching a load-bearing element or the building's common systems requires consent and frequently the general assembly's authorisation. Fixing a pole into a partition is generally straightforward; fixing into the structure is a different question.
Where fixing is not possible, tension systems and freestanding options exist and they are visibly a compromise. The gain from a properly hung pole is large enough to be worth asking for permission in writing.
Colour and pattern
Under flat grey light, a strong pattern on the largest textile surface in a room dominates it for five months of the year.
An unpatterned fabric in a tone close to the wall makes the room read as larger and lets the curtain function as texture rather than as an object. Where colour is wanted, the curtain is a substantial commitment and a rug or seating is usually the better place for it.
What to measure before buying
Ceiling height, since the pole goes near it. The width of the window plus 20 to 30 cm each side. The drop from pole to floor, or to just above a radiator. The reveal depth, which tells you how far the pole must project. And the position of any obstruction: a light fitting, a shelf, a door swing.
Fabric ordered without those five is fabric ordered twice.
Three questions we are asked
Blinds or curtains? Blinds sit inside the reveal and cover glass, which is the problem this article is about. They suit a kitchen or a bathroom; for a living room, curtains hung high do more.
Do curtains really affect heating? Lined curtains over single glazing, measurably. Over modern double glazing in a Kirchberg or Cloche d'Or apartment, considerably less.
How much fabric? Roughly twice the pole width for a proper gather. Flat panels read as a temporary arrangement, which is usually what people are trying to move away from.
The order to do it in
Curtains are usually bought before the pole position is decided, which is why so many end up hung inside the reveal.
Decide the pole height first, close to the ceiling. Decide the pole width second, extending 20 to 30 cm beyond the reveal each side. Check the fixing is permitted and possible, and photograph the wall. Only then measure the drop and order the fabric, allowing roughly twice the pole width for a proper gather.
Where a radiator sits under the window, decide before ordering whether the curtain stops above it or the seating moves, since that decision changes the drop by half a metre and cannot be corrected afterwards without re-hemming.
Three questions we are asked
Should curtains match the walls? Close in tone rather than matching exactly. That makes the window read as part of the wall and the room as larger, which is the point of hanging high in the first place.
Can I hang curtains in a rental? Usually, with consent for the fixing. Ask in writing, photograph before and after, and keep the hardware, since it moves to the next apartment and the fabric frequently does too.
Do I need a track or a pole? A pole is simpler and reads better in most rooms. A track suits a bay or a run that turns a corner, which is uncommon in Luxembourg apartments.
Editorial note: This is a design framework rather than advice on a specific property. In a Luxembourg copropriété, the facade, structural walls and building systems are common parts, so anything fixed, wired or visible from outside may require the landlord’s consent or the general assembly’s authorisation. Check your lease or your règlement de copropriété before work.