Name: stopping white salt crystals on masonry
Uploaded: 2024-09-12T16:16:29.000Z
Duration: 1 min 25 s
Channel: JoVE

L’efflorescence apparaît sous la forme d’une tache de poudre cristalline, souvent de couleur blanche, sur les surfaces de maçonnerie de brique, de pierre ou de béton.
Lorsque l’eau s’infiltre dans la surface de la maçonnerie, les sels alcalins solubles dans l’eau présents dans les éléments de maçonnerie ou le mortier se dissolvent dans l’eau.
Finalement, cette eau migre vers la surface et s’évapore, laissant derrière elle des dépôts de sels à la surface de la maçonnerie.
L’efflorescence qui se produit peu de temps après l’achèvement de la construction peut être nettoyée à l’aide d’eau et d’une brosse.
Bien que l’efflorescence puisse réapparaître, des agents naturels comme la pluie peuvent emporter les dépôts de sel et, avec le temps, l’efflorescence diminue à mesure que les sels s’échappent progressivement de la maçonnerie.
L’efflorescence apparaissant sur les murs de maçonnerie d’un bâtiment après plusieurs années indique que l’eau a récemment commencé à pénétrer dans le mur.
La rectification de la source de fuite permettra de contrôler d’autres occurrences d’efflorescence.
Pour éviter l’efflorescence, des éléments de maçonnerie et du mortier exempts de sels solubles dans l’eau sont utilisés, et l’intrusion d’eau dans les murs de maçonnerie est minimisée.
Les murs peuvent être abrités en assurant un drainage adéquat du toit ou en appliquant des barrières imperméables qui empêchent l’entrée d’humidité externe tout en permettant la migration de la vapeur d’eau vers l’extérieur.

efflorescence dans la maçonnerie

Efflorescence in Masonry

L'efflorescence dans les murs de maçonnerie se présente sous la forme d'une poudre cristalline pelucheuse, souvent blanche, résultant de sels hydrosolubles dans la maçonnerie ou le mortier. Lorsque l'eau pénètre dans la maçonnerie, elle dissout ces sels et les ramène à la surface, où ils se déposent lors de l'évaporation de l'eau.

Si l'efflorescence initiale est courante après la construction et peut être nettoyée avec de l'eau et une brosse, dans certains cas, l'efflorescence peut réapparaître et diminuer progressivement au fil du temps à mesure que les sels sont lessivés des surfaces de maçonnerie lorsqu'elles sont exposées à des agents naturels tels que la pluie. Cependant, l'efflorescence apparaissant sur les surfaces de maçonnerie dans les dernières années de l'achèvement de la construction indique de nouvelles fuites d'eau. Dans de tels cas, la source de la fuite d'eau doit être identifiée et réparée.

L'efflorescence peut être évitée en utilisant des éléments de maçonnerie testés pour l'absence de sels solubles et en employant des ingrédients de mortier propres. La minimisation de l'intrusion d'eau dans les surfaces de maçonnerie réduit également l'efflorescence. Cela se fait en assurant un drainage adéquat du toit et en prévoyant des surplombs de toit abrités dans la mesure du possible. De plus, l'application de revêtements sur le mur qui empêchent la pénétration de l'humidité sans entraver le mouvement de la vapeur d'eau vers l'extérieur empêche l'efflorescence. Dans certains cas, la construction de murs creux peut être préférable à la construction de murs pleins, offrant une barrière supplémentaire contre l'intrusion d'humidité.

Efflorescence dans la maçonnerie

L’efflorescence apparaît sous la forme d’une tache de poudre cristalline, souvent de couleur blanche, sur les surfaces de maçonnerie de brique, de pierre ou de béton.
Lorsque l’eau s’infiltre dans le...

Education

Enseignement

JoVE Core

Civil Engineering

Génie civil

Unit 1

Unité 1

Masonry

Maçonnerie

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

stopping white salt crystals on masonry

Efflorescence is the white, fluffy crystal layer that can form on masonry walls. It happens when water-soluble salts in brick, stone, concrete, or mortar are dissolved by water and carried to the surface. When the water evaporates, the salts are left behind as a powdery deposit.

New efflorescence is often seen soon after construction. In many cases, it can be cleaned with water and a brush. It may also fade over time as rain leaches salts out of the masonry surface. If efflorescence appears years after a building is finished, it often points to a new water leak that should be found and repaired.

Efflorescence can be reduced by choosing masonry units that have been tested for low soluble salts and by using clean mortar ingredients. Limiting water intrusion also helps. Good roof drainage, roof overhangs where possible, and wall coatings that block moisture but still let water vapor escape can all lower the risk. In some buildings, cavity wall construction gives extra protection against moisture compared with solid wall construction.

Stopping White Salt Crystals on Masonry

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efflorescence in masonry

Efflorescence is the white, fluffy crystal layer that can form on masonry walls. It happens when water-soluble salts in brick, stone, concrete, or mortar are dissolved by water and carried to the surface. When the water evaporates, the salts are left behind as a powdery deposit. New efflorescence is often seen soon after construction. In many cases, it can be cleaned with water and a brush. It may also fade over time as rain leaches salts out of the masonry surface. If efflorescence appears...

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key terms and concepts

Learn why white salt crystals form on masonry walls, how to clean early efflorescence, and how to prevent it with better drainage and moisture control.

Stopping White Salt Crystals on Masonry | JoVE K12

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

civil engineering

Stopping White Salt Crystals on Masonry

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