AY Honors/Mosaic Tile/Answer Key

Mosaic Tile

Skill Level

1

Year

2020

Version

27.11.2024

Approval authority

North American Division

1

Give a brief history of tile.

1a

When was it first used?

1b

What were two common uses throughout history?

Ceramic tiles are one of the oldest forms of decorative art. Together with architecture, they have been widely used due to its durability, technical properties and visual richness. The word “tile” comes from the French word “tuile”, which is derived from the Latin word “tegula”, meaning a roof tile of baked clay. As for the word “ceramic”, it comes from the Greek word “keramikos”, which meant “of pottery” or “for pottery”, and it is related to the Indo-European word “cheros”, which means “heat”.

The history of ceramic tiles begins with the oldest civilizations. It is known that Egyptians on the 4th millennium b.c. already used to decorate their houses with blue tile bricks. The glazed bricks were also very common in Mesopotamia; one of its famous applications is the Ishtar Door of Babylon. Originally considered one of the World Seven Wonders, it was built on the 5th century b.c. and decorated with lions, bulls and dragons with a strong glazed blue as background.

The Islamic Empires were responsible for the dissemination of the ceramic tile as a wall covering. Initially mosaics were used resembling the byzantine ones, creating drawings from pieces of stones. But soon enough, under the ceramic Chinese influence accessible through the silk routes, the ceramic tiles with its glaze and drawings began being used. By now they were thicker and widely used in Islamic architecture, as an inside and outside covering, as seen at the monumental public buildings of the Iranian city of Isfahan, the capital of the Safavid empire on the 16th century.

During the Ottoman Empire became famous a kind of ceramic tile from a Turkish city near Istanbul called Iznik. The Iznik tiles had a special glow due to its quartz layers, and shades of red never achieved before. Tiles motifs were generally floral, geometric or Koran passages with beautiful Arabic calligraphy. The Iznik tiles ended up being widely used inside mosques because they helped to resonate the sound of prayers and also gave a feeling of amplitude, taking away the weight of the heavy structure.

In the Iberian Peninsula the ceramic tiles were introduced by the Moors. At the palace of Alhambra in Granada, constructed by the Nasrid Kings in the 13th and 14th century, it is possible to see an incredible work of art. The ceramic tiles were used there in different shapes and colors, and applied to the walls creating beautiful geometric patterns.

However, it was Portugal after the 16th century that truly embraced the ceramic tile art and made it one of its cultural expressions. By now they were done in a squared shape, usually measuring 5,5 inches. The ceramic tiles were used back then everywhere, from public places to private and religious ones, on outside and inside walls.

Very popular on the 17th century, the Dutch tiles from Delft were usually decorated with central figures and delicate ones on the four edges of each piece, creating a united appearance when together combined. These tiles suffered great influence from the white and blue Chinese Ming porcelain, which was imported by the Dutch East India Company and had became a fashion back them.

2

What type of material is tile commonly made of?

Ceramic, Stone such as Granite, Marble, Quartzite, glass

3

What is the difference between glazed and unglazed tile?

In terms of how they are manufactured, there is no difference between glazed and unglazed ceramic and porcelain tile, other than the fact that glazed tiles undergo an additional phase in the firing process. During this additional process, a layer of liquid glass is added to glazed tiles by means of very high temperatures.

Unglazed tiles tend to be denser and thicker than glazed tiles, and because of their unfinished exteriors, they tend to be a great choice if you’re looking for a slip resistant surface in an area like a laundry room or kitchen where the tile is likely to be subjected to high amounts of moisture. In terms of safety, this is a big consideration. For areas with heavy foot traffic, as well as outdoor applications (in milder climates), unglazed tiles are a very good choice.

Along with safety benefits, unglazed ceramic and porcelain tiles are sought after because of their scratch resistance and natural beauty. Since they’re colored by the mineral deposits from where the clay was originally taken, these tiles offer an earthy aesthetic quality. A limitation of unglazed ceramic and porcelain is their vulnerability to staining. As a precaution, it’s a good idea to use a sealant and wax after installing unglazed ceramic tile indoors.

Although glazed ceramic and porcelain tile are a little less robust in terms of density and thickness than their unglazed counterpart, they allow for a wider range of styles and colors. Glazed tiles also tend to be more resistant to staining, as they’re protected by a non-porous layer of liquid glass.

Whether you choose glazed or unglazed tile, both types have their own unique qualities. As always, it’s best to know the needs of your space and the look you are after. This way, your flooring project will be something you can enjoy for many years in the future.

4

What is the difference between sanded and unsanded grout? In what applications is each type used?

Tile grout acts like a mortar that binds the tiles together, but it also keeps moisture out and helps ensure the tiles stay a certain distance apart. A variety of grouts are available commercially, but all of these can be classified as one of two basic types: sanded or unsanded. The right choice for your tile depends on the type of tiles you’re installing and the size of the joint between them.

The main difference between unsanded and sanded grout is the presence or absence of sand. Unsanded cement-based grout is a smooth mixture of Portland cement, powdered pigments and water. Epoxy grouts are made of resin and hardener. Sanded cement-based grout and sanded epoxy grouts are basically the same as the previously mentioned mixtures but with sand added. The sand thickens the grout to prevent shrinking in the joints.

Both cement-based grouts and epoxy grouts come in sanded and unsanded types and can both be used with floor and wall tiles. Cement-based grouts are traditionally used in residential applications. Epoxy grouts are more ideal for situations where the tiles will be exposed to harsh materials, such as acids and greases.

Unsanded grout should be used in joints that are less than 1/8-inch-wide. It has a smooth texture and clings well to vertical surfaces, which makes it useful for grouting ceramic wall tiles. Sanded grout should be used for flooring and wall tile joints wider than 1/8 inch because it resists shrinkage and cracking. It is possible to use sanded grout in thinner joints, but forcing the bulky mixture into these joints is difficult, and pinholes may occur in your finished grout lines. Joints larger than 3/8 inch need heavily-sanded grout mixture, which is typically labeled as a wide-joint mixture and is available at most hardware and flooring stores.

The size of the tile joint usually dictates which type of grout to use, but sometimes the type of tile is the deciding factor. For example, unsanded grout is recommended for highly polished, easily scratched tiles such as marble because the aggregate in sanded grouts may damage these types of tiles. Unsanded grout should not be used in floor tiles, however, because the grout can crack and break under the pressure of floor traffic.

5

List three tools commonly used for tile installation.

• Tile Cutter
• Diamond Drill Bit
• Tile Mortar Mixer
• Buckets
• Tile Trowel
• Rubber Grout Float
• Tile Spacers
• Sponge
• Knee Pads
• Level
• Tape Measure

6

Do the following:

6a

List two tools commonly used to cut tile.

• Manual Tile Cutter
• Wet Tile Saw
• Tile Nippers
• Rotary Cutting Tools
• Oscillating Multi-Tool

6b

Demonstrate the ability to cut tile using one of these tools.

By completing the project in Requirement #9, the Pathfinder should be able to show their skill in cutting tile using a tool from the list above.

7

Describe how to properly apply grout.

Good grout makes for a great tile job and here is the best way to apply grout. After the grout is totally mixed, apply a generous amount to the tile surface and use a foam tile float to distribute it completely filling the tile joints all the way to the bottom by pressing firmly. Once the joints are filled, hold the float at a steep angle and begin removing excess grout from the face of the tile. Always move in a diagonal direction. If you don’t, you run the risk of scooping out grout from the joints you just filled. Dip a cellulose grout sponge in water and wring out most but not all of the water. Then wash the face of the tiles, being careful not to pull the grout out of the joints. Cutting the sponge in half on a tile saw creates a nice square edge that’s ideal for getting into corners. For a final rinsing, dip the sponge in clean water and wring it out thoroughly. Then tip the sponge up so that only the leading edge is touching the tile. Move diagonally across the surface with straight overlapping strokes. Every couple of strokes, flip the sponge around and use one of the remaining clean edges.

8

Describe how to properly seal and finish a tile project.

9

Complete a tile project such as a trivet, potholder, or other household items. The item should be at least 6” x 6” (15.25 cm x 15.25 cm).

References

• Ceramic Tiles History
• Characteristics of glazed and unglazed tile
• Sanded vs. nonsanded grout tile
• Tile cutting tools
• How to apply tile grout