It is not unusual for water to penetrate into the grout joints, but perhaps there are excessive voids behind the tiles. Industry standards say you can't have more than 5% voids behind a tile that 5% should be dispersed.
Grout Is Porous
Grout is the sandy, cement-based filler used between tiles. While grout seals the spaces between tiles, it is still porous, meaning water can seep through. Over time, the porous nature of grout allows moisture to penetrate deeper into the wall cavity.
Efflorescence is a common tile, stone, concrete, brick and grout problem. In this case, the efflorescence is caused by water soaking through the tile grout under the tiles and then evaporating to the surface.
Hi, welcome to the forum, unfortunately cement based grouts are not waterproof, they can be sealed which helps but epoxy grout is waterproof and won't stain.. Be careful with the grout tool that you don't run it too deep and damage the former tray..
The most common reason grout crumbles and disintegrates with minimal force is water - too much water. Virtually all powdered wall and sanded floor grouts are made from Portland cement. Some grouts have additives, such as powdered latex or acrylic modifiers, that make them bond even better.
You can make adjustments by adding more or less water and/or powder. If you're mixing grout for your walls, it should have a strong, thick consistency. It should be easily moldable and not too moist, similar to bread dough. Floor grout will be a bit smoother, like peanut butter.
Portland cement based grouts are particularly porous. Porous grouts attract water, dirt, oils, etc. While the tile industry does not require sealing, it is always recommended, especially in wet or high-traffic areas. Penetrating sealers are the most commonly used and offer high water, chemical and stain resistance.
A question we're often asked is, “how long should grout last in my bathroom last?” Grout doesn't last forever and has a lifespan of between eight and sixteen years, depending on your upkeep and treatment in your shower area specifically.
The walls connected to the flooring can absorb the water, causing water damage and mold to grow on and in the wall, as well as loosen any tiles attached. This loosening is due to the water damaging the grout between the tiles, and loosening the tiles adhesive.
ANSWER - Water coming up through your tile grout joints is an indication that you have a high water table on your property or that water is being directed towards your house, and you don't have a vapor retarder under the concrete slab to prevent water from migrating through the concrete.
Medium to heavy showers will weaken the slurry formula and, once dried, cause it to crack and break. An excess of water in the grout can cause paving failures, stains, or efflorescence further down the line.
The most common area where leaks will occur is in the areas where grout has been used to bind or seal the material chosen for the install. This issue is mostly caused by a building moving over time and this shift will generate cracks in the grout.
Check pipes, drains and gutters
A leaky pipe, blocked drain or a clogged gutter could be the culprit behind your mysterious damp patch. If safe to do so, inspect the pipes and fixtures for broken seals or rusted exteriors, as these could all be potential sources of the leak.
For clear defects in the tiled shower surface, grout replacement will usually rectify your water leak.
Moisture and direct water contact contribute to grout deterioration over time, and eventually, the tiles will crack. This is why you should consider regrouting shower tiles every six months. This is a quick and budget-friendly fix that can restore your bathroom's previous glow immediately.
Steam cleaning is one of the most powerful ways to clean grout without the use of harsh chemicals. Professionals often use steam to loosen the dirt and other particles trapped in the grout without needing to scrub manually.
Grout can absorb water, creating a breeding ground for mold when paired with excess moisture. Virtually every shower forms soap scum, an organic matter that mold thrives on.
If your grout is visibly cracked or crumbling, it's likely going to be letting water behind your tiles. Even if your grout doesn't appear to be damaged, if it's not water-resistant it could potentially be the source of the leak.
Grout helps hold tiles in place, preventing them from shifting and becoming loose. Unsealed grout is susceptible to moisture penetration, which can lead to the deterioration of the grout itself. Over time, this degradation can result in weakened grout lines and tiles that may become loose or crack.
Epoxy grout: Waterproof, durable, stain- and shrink-resistant. The best grout in shower walls, backsplashes and other surfaces susceptible to moisture or stains. Ideal for use with unglazed and other tiles.
If you have a high water table the french drain won't keep the water away from the bottom of your concrete slab. So the water from the high water table must be in contact with the concrete slab so the water migrates into the concrete slab and up through the grout joint.
As mentioned earlier, the specific recommended waiting time for grout to set and dry will vary based on the product and brand you are using. However, a common guideline is to wait approximately 15 to 30 minutes after applying the grout before wiping off the excess.
Tile and grout is not totally waterproof and neither is cement board, backer board, sealers and cement adhesives, they absorb water but do not block penetration.