Ceramic Tile Basement Floors

Basement ceramic tile floors
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Ceramic is a water resistant, resilient, easy to maintain flooring option, that is appropriate for many basement subgrade installations. However, there are a number of precautions that need to be taken during and after installation, to ensure the integrity of the floor. There are also certain risks associated with using almost any material in a below-grade environment.

Installing a Ceramic Tile Basement Floor

In a basement, the best subfloor you can use for ceramic is the cement slab that acts as the foundation of the building itself.

Installing a plywood subfloor can lead to water penetrating up through the slab and warping the wood.

This moisture generally isn’t an issue for a ceramic floor. However, in very wet, flood-prone areas, a water barrier or vapor barrier layer can be installed between the ceramic and the cement to help stop moisture from affecting the adhesive gripping the tiles above.

Before installation can begin the cement subfloor needs to be carefully prepared. It should be smoothed out, sanded, and made completely flat and even. If there are dips or cracks, the filler should be used to repair them. The integrity of the subfloor will affect the entire life of the ceramic floor above. If there are gaps or rises in it, these can become weak points lurking beneath the tiles.

In most cases, the smooth surface of the concrete will then have to be scarred slightly, in order to create a texture that the tile adhesive can bond to.

Any resultant dust or debris then needs to be removed with a vacuum. Then, finally, the adhesive can be spread, and the ceramic floor can be installed according to the manufacturer's directions.

Professional Installation: This is a personal choice. Ceramic tiles are heavy, and you will have to carry them down the stairs yourself, and then painstakingly lay each piece one by one.

The process can take several days and needs to be done right to ensure the strength of the floor after it is complete. You should only undertake this process if you are confident in your endurance and your tiling skills.

Professional Versus DIY Installations

Ceramic Tile Water Advantages

The glazed surface of a ceramic tile is impervious to moisture. However, any unglazed surfaces are not, and can be prone to liquid penetration. In addition, the grout lines are not protected and will need to be sealed to make the surface impervious. The tiles themselves will also be resistant to the growth of mold, although the grout lines between them are still quite susceptible.

Ceramic Basement Flooring After a Flood

The survival of a ceramic basement floor after a flood will depend on the quality of the initial install. Glazed ceramic tile surfaces are impervious to water, and can remain immersed indefinitely. However, the grout lines between those tiles can be insidious cracks that allow harmful moisture in.

After ceramics are installed in a basement, the grout lines need to be treated with a quality water barrier sealer. This will create an impervious layer, which will stretch across the tile and the grout like an invisible sheet, stopping any liquids from penetrating down.

This seal needs to be reapplied periodically every 6 - 12 months.

If the sealer layer is still intact during a flood then there is a chance that it will reduce the amount of water that can penetrate the floor.

Immediately after a flood, the first thing you need to do is get things as dry as you can as quickly as possible. Letting moisture sit and settle can lead to mold problems later on. Once the standing water had been drained you should open all windows and use fans to circulate humid air out of the space. A dehumidifier can also be used to try and sap the liquids that linger behind in the air.

The extent of the damage will then have to be determined. If grout lines are compromised they may start to rot and fleck away. These can be removed with a grout knife, and then replaced once the whole installation is dry again.

If the water penetration is even more extensive than the adhesive beneath the ceramics may start to come loose. This will require removing, cleaning, and replace sections of the floor.

You can use moisture meters to determine the level of liquid in the air, and in certain parts of the floor. You may also want to consider removing about 12 inches of the floor touching drywall from a section of the wall to see if the water was able to penetrate down through those seams.

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Cold Ceramic Basement Flooring

Another issue that you will run into with below grade ceramic flooring installations is that they can be very cold. The basement is a room which is already subterranean so you want to do everything in your power to make it feel warmer. Unfortunately, ceramics need to be installed directly on the cement foundation slab of the house. This slab interacts with the outside environment and can get quite cold, chilling the entire floor.

One solution is to install a layer of padding as an underlayment between the cement subfloor and the ceramic tiles. This should be laid in conjunction with a vapor barrier layer, to protect the padding from the water. This layer will then act as insulation, holding the heat of the room in, while standing between the cold concrete subfloor and the actual ceramic surface.

Radiant below floor heating systems can also be installed with ceramic basement floors. The radiant heat coils go beneath the tiles, and heat up, sending toasty warmth shooting through the material. This simple installation can go a long way towards heating up what may otherwise be a cold, impersonal finished basement.

Finally, carpets and rugs can also be used as a stopgap measure to create both warmth, and soft within the basement. If you are feeling fancy then electrically heated foot mats can be purchased to create a sense of warm whimsy within this space. 

More About Ceramic Flooring

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Purchasing Ceramic Tiles