Cement as a Home Material: Raw, Calm, Surprisingly Easy to Care For

Why cement works in calm rooms

Cement has an even, matt surface without markings. That is exactly what makes it useful where materials with strong veining would be too much. Next to travertine, wood and leather, it acts as a calm surface that tells no story and therefore drowns nothing out.

The shape is created entirely in the casting mould. Whatever the mould dictates, the material reproduces – down to edges, radii and the texture of the mould wall. That is why cement objects often have clear, geometric outlines: they are the obvious choice in terms of production, and they suit a surface that brings no markings of its own anyway.

The surface itself can also be controlled. Fine aggregate and a smooth mould produce a dense, satin-matt surface; coarser sand or an open casting face produces a sandier appearance. Both remain matt. Cement does not shine by itself – a sheen always comes from a coating or a polish, never from the material.

Hand-cast means uneven

With industrial concrete, uniformity is the goal. With hand-cast objects it cannot be achieved, and that is intended.

Each batch dries under slightly different conditions. Temperature and humidity during curing determine the colour tone; small air pockets on the surface form where the mass was not fully compacted in the mould. For the same reason, almost every surface shows fine shading and a structure of its own.

Then there is the amount of mixing water. More water makes the mass more fluid and the mould easier to fill, but it increases the porosity of the cured material and affects the colour tone. Two casts of the same recipe can therefore differ simply because of slightly different handling.

The process is not finished with demoulding in any case. Cement continues to set over weeks and only reaches its final strength after a longer period. During this phase the tone can still change slightly; usually it lightens as residual moisture escapes.

Anyone who buys two vases and expects exactly the same colour tone will see a difference. With a cast material this is not a defect but part of the process.

What a sealant really does

Cement is absorbent. Without treatment it takes up water, oil and dyes, and a drop of red wine remains visible.

A stain-protection sealant, as is usual on decorative cement objects, does not close the pores; it delays penetration – liquid stays on top long enough to be wiped off. Provided you actually wipe it. Leave a drop overnight and the advantage is lost.

Broadly, two approaches can be distinguished. An impregnating sealant soaks into the material, narrows the pores and leaves the surface visually unchanged, matt and open. A film-forming sealant lies on top as a thin layer, keeps liquid out more reliably, but in return changes the character of the surface and can have a slight sheen.

Neither is permanent. Every sealant wears with cleaning and use and can be renewed – the time has come when a drop of water no longer beads but leaves dark rings.

To care for it, use a damp cloth. Aggressive cleaners are unnecessary; strong acids attack the lime content, much as with travertine.

Outdoors and indoors

Cement itself is weather-resistant. Sun, rain and normal changes in temperature do little to the cured material, and UV light does not bleach it as happens with plastic or textiles. Cement objects are therefore often suitable for outdoor use.

What changes outdoors is the appearance. In permanently damp, shady positions, algae and moss settle, and efflorescence can emerge from the material itself: dissolved lime travels to the surface with the moisture, reacts there with the air and remains as a pale haze. Both are harmless and can be removed mechanically. Leave them, and you get a patina.

One real limitation remains nonetheless: frost. A porous material that has become saturated with water and then freezes works against itself, because ice expands. After some years, fine spalling appears at the edges. Bringing cement objects under cover or indoors over the winter extends their life considerably. Vessels in which water stands are particularly vulnerable.

The second point concerns plants: fresh cement releases alkalis for weeks, which can harm sensitive roots. For a cement planter, an inner pot made of plastic or terracotta is simpler than planting directly into it.

Cement versus natural stone

Both have a matt, mineral surface, both feel cool, both look heavy and solid. The difference lies in the markings.

Natural stone has them and is therefore an object that receives attention. Cement does not have them and is therefore an object that gives attention. In a room with many calm surfaces, travertine is the better fit. In a room with a lot of wood, pattern and textile, cement is the more honest material.

That cement has to be grey and heavy is one of the more persistent assumptions. The colour tone depends on the binder: cement with a higher iron content produces the familiar grey tones, whereas low-iron white cement produces pale, almost cream-coloured surfaces, and pigments extend the range further. And because it is cast rather than worked from a block, thin walls are possible. Smaller objects therefore often weigh considerably less than their stone-like appearance suggests.

And in price: a cast cement object costs a fraction of a comparable stone object, because no block has to be sawn and no surface polished.