Can we leave a concrete block wall unclad? Complete guide

A rough concrete block wall can have its charm. Industrial look, concrete clear and clean lines: it’s a temptation leave as it is rather thancoat. In the reality of the construction site, we arbitrate between cost, sustainability et aesthetic. We at InspiMaison guide you simply, precisely and without unnecessary jargon. Let’s talk concrete block walls, covering, color, cement, mortar and little tips from a craftsman.

Before deciding, let’s distinguish the contexts: internal, shelter, garage, fence OR facade visible from the public road. The constraints are not the same. From a technical perspective, an uncoated concrete block does not offer the same waterproofing nor the same insulation of a protected wall. On the rules side, theexternal appearance is framed by PLU and some procedures (prior declaration). Let’s take stock, then I’ll give you some alternatives credible and gestures ofinterview deposit your cinder block wall.

The advantages of an unclad concrete block wall

First good: the simplicity. Not cover the wall with concrete blocks It saves time, especially in an outbuilding or in a technical room. NO concrete mixer to be relaunched for a mortar D’coveringwithout multiple drying times. THE cost direct reduction: fewer materials, less labor. In a workshop style interior, the concrete block without facing it creates a very contemporary raw atmosphere. We can then cover the wall with concrete blocks by areas (shelves, panels) without immobilizing the entire site.

Second advantage: the reversibility. Leaving the wall raw allows you to observe the concrete block defects (microcracks, hollow joints) before deciding. You can prepare the wall later, then place a cladding coating oh covering. For a garage or cellar, a simple water-repellent and one color sometimes technique is enough. We maintain the possibility ofcoat subsequently if the use of the premises changes, or install a covering without removing a facade cladding existing.

The disadvantages of an uncoated concrete block wall

The opposite is thehumidity. The concrete block is capillary. Sans covering In coveringwater penetrates more easily through the joints mortar. Inside there are traces of saltpeter and dust cement. It’s worse outside: the pouring rain and strong winds damage the skin of the block. In the long term, the sustainability From concrete block building it degrades if water settles, especially in exposed areas. THE’waterproofing the surface becomes a real subject.

Another limit: theinsulation. AND concrete block wall uncoated cuts poorly Cold and the noise. Even a skinny one facade cladding slightly improves air tightness; a rough wall lets dust and sometimes micro drafts pass through. Side aestheticthe rendering might look like a “construction site” if the concrete blocks are heterogeneous or if the beams and the networks remain visible. Brief, uncoated concrete blocks rhymes with more frequent maintenance… and visual concessions.

Rules and regulations around unclad concrete block walls

In a house, you can legally leave a wall blank ? alinternalyes, in general. AloutsidetheI wait of facade is classified: depending on the Municipality, the PLU can impose on covering or a front for concrete block walls visible from the street. As soon as you change the external appearance (for example changing from a rough concrete block to a cladding or changing colour), a preventive declaration (DP) may be required. This is the case of ITE, which changes its appearance, and often of renovation in a protected sector.

For a fence In concrete blockthe PD depends on the sector and the PLU; some municipalities require a covering oh height limited. Check with the city planning department first build wall or leave a concrete block wall « uncoated » at the edge of the property. The reference texts cite the PD for interventions to modify the external appearance and specify the cases in which it applies, in particular in protected areas.

Technical risks and durability of a wall without cladding

Without protection, water finds the defects : irregular joints, broken edges, cement too rich or not tight enough. THE come/dégel can peel the skin of the block. On the ground floor, the capillary rises stain the bottom of the wall. Inside, ambient air captures dust concrete ; to the touch, the dust of the wall. Outside, the facade gets dirty more quickly. These phenomena are not catastrophic the first winter, but add up over time.

Another point: the compatibility with future work. A uncoated concrete block poorly protected, hangs less well for some roofing. If you are considering a cladding coating after, take care of preparation : plug the gravel nests, cover the wall with concrete blocks occasionally, grind the joints of mortar. So the day you move onfacade cladding or to a coveringadhesion and flatness will be present.

Alternatives to traditional cladding for a concrete block wall

There is no need to apply a heavy coating to the concrete mixer. There are lightweight options for cover the wall with concrete blocks : color microporous mineral, stain concrete, water-repellent colorless, thin plaster armed. These systems improve thewaterproofing of surface without weighing down the wall. Indoors, at color technical (garage, workshop) resists light impacts and is easy to clean. We can also pose panels OSB or gypsum fibers if you prefer a smooth finish.

From a furnishings point of view, the face brick or stone, the covering ventilated wood or fiber-reinforced concrete slabs offer a clean finish. Sometimes we talk about itcladding coating (fine grain, tight) to preserve the spirit concrete unifying the color. For an industrial style, keep the same concrete block visible but treaty with water repellent it gives a very contemporary matt effect. The idea is to protect the media without distorting it and to remain consistent with the architecture of the concrete block building.

Practical advice for the protection and maintenance of a raw concrete block wall

Start with prepare the wall : dust vigorously, vacuum the joints, close with mortar. Outside, treat sensitive areas (basement, headboards beams) and break the sharp edges that catch the water. Apply to water-repellent quality in two crossed steps. Indoors, at color The opaque acrylic “technical walls” fix dust and facilitate maintenance, without completely masking the environment concrete block.

Then monitor: after each winter, check the cracksinfiltrations, waterproofing supports and penetrations (cables, pipes in concrete block). Clean gently with a nylon brush; Avoid using the pressure washer too close as it may damage the surface. If the exposure is harsh, plan for medium-term exposure covering more protective (thin plaster, facade cladding, covering). This extends the life of the wall by improving its qualityinsulation with, if necessary, a subtle complex.

In short : we can leave the concrete block wall without lining in several cases (internal, annex, non-visible area), as long as the support is protected and local planning is verified. For a facade oh fence visible, queries the PLU and anticipate the prior declaration yes theexternal appearance it evolves. Maintain control between raw control, cladding coating OR covering lightweight, depending on usage and budget.