Guide · 6 min read
Grout Selection, Sealing and Care
Cement versus high-performance versus epoxy grout, why some joints must be silicone, and what sealing does and does not do.
Grout is chosen last and complained about first. It is also the component people are most often misinformed about — particularly around sealing.
Here is the practical version.
Cement-based grout
The traditional option: economical, widely available in many colors, and porous. It absorbs liquid, which means it stains and needs periodic sealing to slow that down. Sanded versions go in wider joints, unsanded in narrow ones and on scratch-prone surfaces like polished stone and glass.
High-performance cement grout
Modified cement grouts with much lower absorption, better color consistency and greater stain resistance. Most do not require sealing. For most residential floors and showers, this is the sensible default now — the cost difference over standard grout is small relative to the labor around it.
Epoxy grout
Essentially non-porous and highly chemical resistant, which makes it excellent for commercial kitchens, heavy-use areas and anywhere aggressive cleaning happens. It is harder to install, less forgiving of mistakes, and more expensive. It is genuinely useful in the right place and overkill in a guest bathroom.
Where grout does not belong
Every change of plane — inside corners, the tub-to-tile joint, the counter-to-backsplash joint, the perimeter of a floor — should be flexible sealant, not grout. These are movement joints. Grout is rigid and will crack there, repeatedly, no matter how well it was mixed.
If someone regrouted your shower corners and they cracked again within a year, this is why.
What sealing actually does
A penetrating sealer makes grout more resistant to absorbing liquid, buying you time to wipe up a spill. It does not make grout waterproof, it does not stop water from passing through a shower wall, and it wears off with cleaning and traffic.
Natural stone tile itself also needs sealing — and in the case of marble and travertine, protection from acidic cleaners, which etch the surface regardless of sealer.
Cleaning without doing damage
Simple habits keep grout looking right longer than any product does.
- Use pH-neutral cleaner; acidic products attack cement grout and etch stone
- Avoid steel wool, scouring powder and abrasive pads on glazed tile and glass
- Squeegee shower walls after use — it removes most of what leaves mineral deposits
- Ventilate the bathroom during and after showers to reduce persistent damp
- Reseal cement grout on the schedule the product specifies, if it requires sealing at all
- Keep a few spare tiles from the original order; a matching repair later is far easier
Choosing a grout color
Matching the tile makes the surface read as one field and makes minor lippage less visible. Contrasting emphasizes the pattern and is the point of a graphic layout like herringbone. Very light grout on a floor and very dark grout in a hard-water shower both show their problems soonest — pick with your maintenance tolerance in mind, not just the showroom lighting.