To find out how to clean tile joints that have turned black, tests may be necessary to ensure that you do not damage the joints concerned. Here’s everything you need to know about grout, the mold that can grow in them, and how to clean them.
Usefulness of tile joints
The first role of seals is to ensure thewall sealing on which the tiles are laid.
In addition, wet rooms are subject to variations in temperature and humidity which can cause very small changes in the dimensions of the tiles. As small as they are, without the joints, cracks could appear. The tile could even burst.
The joints also compensate for the few irregularities that may occur when laying the tiles.
And to complete the list of the roles of tile joints, let’s talk about their decorative effect because they are no longer limited to the single color white.
The composition of tile joints
In a kitchen or bathroom, if the work has been carried out correctly, the product used to grout the tiles contains water-repellent and chemical-resistant products: this makes cleaning easier.
Most modern gaskets contain silica (composed of sand) and l’lower (composed of clay). These two natural materials, present in large quantities in many parts of the world, are resistant to chemical attack. They have properties plastics which allow them to resist the mechanical attacks and the small deformation movements that we mentioned in the previous paragraph.
Mold in tile joints: not only aesthetic inconveniences
If you notice that the joints are blackening, it means that the tiles are in contact with water or laid in a room with high humidity. Indeed, the water that stagnates in the microscopic irregularities of the joints promotes the development of fungi of different colors (green, gray, black) called mold.
Beyond the aesthetic inconveniences they cause, these molds multiply by emitting spores into the atmosphere of your home. If inhaled by a susceptible person, the spores cause irritations mucous membranes of the upper respiratory tract and lead to manifestations such as rhinitis, bronchitis or asthma.
Cleaning tile joints that have turned black
For successful cleaning, don’t wait for mold to grow. Intervene as soon as possible!
The White vinegar is the great classic of daily cleaning products, effective and safe. Vinegar being a fairly strong acid, it is best to do a test beforehand to ensure the resistance of the seal. Once you are confident that the vinegar is safe on the grout to be cleaned, you soak a toothbrush in the solution and scrub the blackened grout. You wait at least 15 minutes before rinsing thoroughly with clean water.
A mix of lemon and coarse salt, applied with a toothbrush, may also work. Coarse salt will add a slightly abrasive action. Thus, in addition to the acid action of the lemon on the moulds, you operate a slightly harder friction than with the toothbrush alone. You leave it on for at least 30 minutes before rinsing thoroughly as before.
L’bleach can be tried as a last resort, if the two previous solutions do not work. However, it must be used with great care because it may whiten the joints. A test on a very small area, in an inconspicuous place, is essential to be sure that the aesthetics of the tiling will be preserved.
If you cannot clean the seals satisfactorily
If no method of cleaning proves satisfactory, it may be necessary to consider a renovation des joints.
Remove 1 to 2 mm from the thickness of the existing seal, using a pointed tool. Then you thoroughly clean, dry and dust the affected surfaces.
You spread the paste for joint renovation as widely as possible and smooth, by a gesture diagonally in relation to the tiles, with a squeegee or a rubber spatula, limiting the surplus on the tiles.
Refer to the instructions indicated on the box of the renovation mortar you are using to find out the pause time before cleaning, which will be done with a slightly damp sponge, without pressing. What is called the residual milt is generally removed with a clean, dry cloth after the seal has dried on the surface (it is dry to the touch but not in depth).
Think about taking action against the development of mold
It is important toventilate wet rooms at least once a day, for at least ten minutes, after activities that produce water vapor (shower, bath, cooking, starting the washing machine, etc.). that the drying of the laundry inside the housing promotes humidity.
If your home is particularly humid, do not hesitate to dry the surfaces after use, or even use a dehumidifier air or a moisture absorber.