Tiling is a big project, and it represents a significant investment. One of the best ways to protect that investment is to not walk on it before the grout and mortar have completely dried, ensuring that your tile stays intact and even for the years to come.
You can walk on tile 24 hours after you grout. Before you grout your tile, the thin-set or mortar must also cure for 24-72 hours. Environmental conditions affect drying times, so waiting longer than 72 hours before applying pressure to freshly grouted tile is always best.
So, let’s talk about how long you’ll have to wait for your grout, mortar, and sealant to dry. I’ll discuss the suggested drying times, the environmental factors that will affect your project, and what exactly grout, mortar, and sealant are.
How Long To Let Grout Cure or Dry
Before applying grout, the mortar must be fully cured or dry. You can grout your tile in as little as 24 hours in hot, dry climates. In cooler, more humid climates, you’ll need to wait longer.
Most tile experts recommend waiting between 48-72 hours for your mortar to set. You can let the mortar dry for longer if needed. Allowing the mortar more than 72 hours to cure will not adversely affect the tile. Just be sure not to walk on the tile or get the surface wet while the mortar sets.
You can apply grout as soon as the mortar is completely dry. If you grout tile too early, air cannot circulate to cure the mortar or thin-set properly. Improperly set mortar crumbles and causes tiles to crack or pop off the wall or floor down the road. Moisture from the un-set mortar can also alter the intended color of the grout.
Grout needs a minimum of 24 hours to dry. Grout sealant needs an additional 72 hours to cure completely and must be applied every year or two for continued protection against water and stains.
How Environmental Factors Affect Your Grout’s Dry Time
Temperature and humidity will affect the dry time of your materials. Places that are cooler or have higher humidity will have longer dry times for both mortar and grout. Using a fan to circulate the air in a room can speed up drying times. Keeping a room warm will also assist in curing the grout faster.
The best time of year for a tile and grout project is summer. The heat will help the mortar and grout cure more quickly. If you live in a particularly humid location, turn on your air conditioner or dehumidifier to speed up the curing process. Humidity can slow the drying because the air is wet. Warm and dry air is best for shortening the time for grout to set.
Grout Curing Strategies for Large Areas
If you have a large, heavily-traveled area to tile, consider tiling it in sections to allow for the free movement of people around the area. You can also create alternative paths in and out of rooms. You can also grout in sections to ensure a large area sets appropriately.
If you must cross over the newly-tiled area, build a bridge. The idea is to minimize the direct contact with the tile to prevent the tiles from slipping or not adhering properly. Laying the tiles in sections also prevents your walking on the freshly-laid tile.
Types of Grout and Their Benefits
There are several types of grout. While placing grout in exceedingly narrow spaces between dry-area tiles isn’t necessary, it helps protect your tile from cracking, shifting, and dirt and debris building up between tiles. You should always apply grout if the gaps in your tiles are greater than .0025 in (.00635 cm).
The types of grout are:
- Epoxy, epoxy resin, and filler powder
- Sanded, a mix of cement, limestone, pigment, and sand
- Unsanded, a blend of cement, limestone, and pigment
Epoxy grout is typically more watertight than traditional forms of grout. It is also stain-resistant and does not need grout sealant. It is more expensive than sanded and unsanded grout.
Sanded grout has all the same ingredients as unsanded grout; it just has sand added. It has less shrinkage than unsanded grout and is more durable. It is suitable for high-traffic areas and tile projects with a ⅛ in (.31 cm) gap between tiles.
Unsanded grout tends to crack with excessive use, so it is better suited for tiling shower walls, backsplashes, and gaps between tiles that are less than a ⅛ in (.31cm). The higher shrinkage rate of unsanded grout does not affect its ability to bond to tile. Nor does it affect the durability of the tile.
Should You Use Grout Sealant?
You should use grout Sealant after applying sanded or unsanded grout to your tile. It takes 72 hours to cure fully.
Grout sealant helps keep water and stains out of grout. Grout sealant requires the grout to be completely dry. Moisture present in the grout will prevent the sealant from permeating the grout.
If it is oil-based, it needs to be applied every year or two to ensure continued protection of the grout.
Grout sealant is either chemically or naturally formulated. Chemically-formulated sealants are either petroleum-based or silicon-based or use fluoropolymers. These chemically formulated sealants can last for up to a decade before they need to be re-applied.
Naturally-formulated sealants are oil-based. The oil protects the grout by penetrating it entirely and thereby repelling water. As oil-based grouts are not as robust as the chemically-formulated sealants, they must be reapplied every year or two.
You do not need it with epoxy grout because it is already waterproof and stain-resistant. However, sanded and unsanded grout will absorb water and stains if not correctly sealed. Over time, it will become discolored and crack.
Before you can walk on your new tile, be sure to give the grout at least 24 hours to dry. Then seal it to keep out moisture and stains. The temperature and humidity of the air will affect how long your mortar and grout take to dry. Tile is a significant investment; to protect it, follow the suggested drying times for mortar and grout.