Grout Cleaning or Regrouting?

I am frequently asked if we do grout cleaning or regrouting and my first question in reply is why. This may seem like a silly question with an obvious answer but the reason for the request is actually important.

Obviously, the grout is dirty or possibly cracking out of the seams. Let’s start with the first reason. Grout may be dirty simply because the cleaning task has been overlooked. City water is full of contaminants and when droplets are left to evaporate from the surface, those contaminants are left behind. Over time, it can be a real chore to clean. But, the problem is often much deeper. The term “builder grade” is not a compliment. Builders usually build to code and this is the bare minimum in quality and in showers, code only requires that the pan doesn’t leak when they check it. All of the materials behind the tile are often the bare minimum, code required, “builder grade” materials. These materials are not waterproof, allowing moisture and water vapor behind the tile. Some materials such as drywall will absorb the moisture, even to the point of saturation creating a very friendly environment for mold. The mold then grows on the material behind the tile gradually extending its reach through the pores of the grout. This makes the grout look dirty. If you have cleaned it, even with bleach, and the dirty appearance soon returns, then this is evidence that you have mold behind your tile. You cannot clean it away.

What about cracked grout? It is entirely possible that the grout is cracking due to improper installation, but if this is the cause, it’ll show up within the first year, likely within the first month. If its been five, ten or 15 years, then this is further evidence structural compromise of the substrate; that is, the material to which the tile is stuck. Grout doesn’t crack (after the first year) unless there is movement. When substrate material absorbs moisture, it swells. Additionally, if it is drywall, once the facing paper gets wet, it looses it structural rigidity. So, if your grout is cracking after several years, you very likely have degraded substrate due to moisture penetration. As we discussed in the previous paragraph, a wet substrate is an ideal environment for mold. It is likely already established.

Back to the original question: should you have your grout professionally cleaned or regrouted? There are very few scenarios where this is a good idea. Grout that won’t come clean or is cracking is good evidence of moisture intrusion into your wall cavity and good evidence of mold growth. Replacing an entire shower is no small investment, but if you do it, make sure it is does not just to code, but in compliance with tile industry standards as set forth by the Tile Council of North America. Ask your installer to provide you a copy of the standard he or she will use. If they can do this, you’ve likely found a competent installer who can fully solve your grout problems.