Books are heavy, they take wall run rather than floor area, and in an apartment the wall is frequently not yours to fix things to. All three constraints have straightforward answers.
Wall run is the constraint, not floor area
A metre of shelving at 30 cm depth holds a surprising number of books, and a metre of floor holds almost none. So the question at every viewing is how much uninterrupted wall exists, not how large the room is.
Measure the longest wall in each room, then every other segment between doors, windows and radiators. Note the ceiling height as well, which in Luxembourg ranges from around three metres in a nineteenth-century conversion to considerably less in a 1970s block, and which determines how much of that wall is usable above head height.
High shelves in a tall room are ideal for books consulted rarely, and they turn an unused strip of wall into the largest single storage gain available in most apartments.
Weight, which matters more here than people expect
A filled bookcase is heavy, and in the converted townhouses that dominate Limpertsberg, Belair and the Gare district the floors are frequently timber over joists.
Two practical consequences. Distribute weight along a wall rather than concentrating it: a long low run is safer than a tall narrow tower. And place heavy runs against a structural wall rather than mid-floor where a plan shows partitions.
Tall units should be secured to the wall in any case, which brings the fixing question.
What you may fix, and to what
In a rental, read the lease before drilling, and photograph each 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. The structure is a common part under the amended law of 16 May 1975, and improvement works require an absolute majority of all millièmes, present or not.
Where fixing is not possible or not permitted, freestanding units that lean or stand independently are the answer, and they should still be weighted low.
Where books should not go
- Against an external wall in an older building, particularly on a low floor or in a valley district, where condensation is more likely. Check the corners of external walls and window reveals for any dark bloom before deciding.
- In front of a radiator. It blocks the heat in a season running roughly October to April and dries the paper unevenly.
- In direct sun. South and west-facing rooms in newer buildings with large glazing will fade spines within a couple of summers.
- In the cave, unless it is demonstrably dry. Check the base of the walls for salt bloom or a tide mark, because a damp cellar stores no paper at all.
Using the walls most apartments waste
Three positions are consistently overlooked in Luxembourg apartments.
Above door height. A shelf running around a room at 2 metres is invisible in use and holds a great deal.
The corridor. Shallow shelving at 20 cm depth on a corridor wall works where the corridor is wide enough that it does not become the narrowest point. Measure at the pinch point before committing.
Deep window reveals. Older converted buildings frequently have them, and a shelf or board across a reveal produces both storage and a seat with the best light in the room.
Light, for reading rather than for the shelves
The sun sets before half past four in late December and a large share of days between November and February are overcast, so a reading position needs its own light for five months.
A directional lamp beside a chair, not a ceiling fitting overhead, and an ambient source elsewhere so the contrast is not tiring. Check the number of ceiling points and the position of every socket at the viewing, because unfurnished Luxembourg lettings frequently come with bare fixtures or none, and anything wired requires the landlord's consent in a rental.
Keeping it from becoming storage
A bookcase in a small apartment accumulates objects that are not books, and at that point it stops reading as a library and starts reading as clutter.
One discipline handles it: books only, everything else in closed storage. It also has an acoustic benefit, since irregular mass on a wall scatters sound and reduces the reverberation that makes a hard room tiring and calls sound poor.
Three questions we are asked
How deep should shelves be? Around 25 to 30 cm for most books. Deeper wastes wall run and encourages double-stacking, which makes the collection unusable.
Is a built-in library worth it in an owned apartment? For a long hold, on a wall run, yes. Highly specific joinery narrows the pool of future buyers, which affects how quickly a property sells rather than what it is worth on paper.
What if there is no wall at all? Use the corridor and the space above door height before concluding there is none. Between them, most Luxembourg apartments have more usable wall than a first look suggests.
What to check at a viewing
Four measurements decide whether a home library is possible, and none appears in a listing.
The longest uninterrupted wall in each room, and every other segment between doors, windows and radiators. The ceiling height, since above door height is the largest single storage gain available in most apartments. The width of the corridor at its narrowest point, since shallow shelving there works only where it does not become the pinch point. And whether the walls are structural or partition, which the drawn wall thickness on a floor plan will usually indicate.
Then check the practical constraints: the socket positions for a reading light, whether any external wall shows a dark bloom in the corners or reveals, and the size of the cave, measured rather than described, for anything that has to be stored rather than shelved.
Three questions we are asked
Should books go in the bedroom? They work well there acoustically, since irregular mass on a wall reduces reverberation, and the bedroom is frequently the room with the most uninterrupted wall in a Luxembourg apartment.
What about a reading chair? It needs less space than people assume and it needs its own directional light rather than a ceiling fitting. A deep window reveal in an older building frequently makes the best reading position in the apartment.
Is it worth reducing the collection? Before moving, yes. Books are the heaviest thing in most households, and a lift car or a narrow stairwell in a converted building is a real constraint on moving day.
Building it over time
A library assembled at once rarely fits the apartment; one assembled over a year fits it precisely, because each addition is measured against what actually remains.
Start with one wall run, adjustable rather than fixed-shelf, on the longest uninterrupted wall. Fill it before adding a second. Then look at the positions most apartments waste: above door height, the corridor at shallow depth, and any deep window reveal. Between them, most Luxembourg apartments hold more than a first assessment suggests, and none of those positions requires surrendering floor area.
Editorial note: Building rules, communal regulations and market practice in Luxembourg vary and change. This is a framework rather than advice on a specific property. Check your lease, your règlement de copropriété and your commune before relying on any of the above.