|Tile expansion Joint วันที่ 22/03/2015 08:00:13 AM ,ผู้เข้าชม : 2217 |
Tile expansion Joint
Most of the homes, offices, shopping malls and shops are now installed with tiles everywhere. Tiles are very common material for walls and floor for both exterior and interior. They are also used for wet areas like kitchen, bathroom and swimming pool. They enhance the beauty of a home, they are highly durable and lasts lifelong if properly maintained. The maintenance cost is low and it is easy to maintain. The tiles come into various design and shapes. They are easy to install and can support huge foot traffic. The tiles can be installed using tile adhesive and grouting.
Why do you need expansion joint?
In simple words the answer is expansion joints are needed to prevent the movement of the tiles, everything in the construction world moves and this movement can cause materials to fall apart. The tiles are the surface of the floor and every type of traffic takes place on it, movement joints are needed to decrease stresses that occurs between the substrate and the tile due to differing amounts of expansion and contraction. In bigger rooms, this expansion joints should be done every 15-20feet. Without this expansion joints which works as pressure-volumetric compensator, there is a high possibility that the tile may get crack and contract when temperature changes. Tile moved off the floor and sometimes cracked is often a sign that movement joints were not used sufficiently. For tile over concrete, the curing of the concrete places the tile under compression. Anyone who lives in a tiles house for more than one or two years knows how temperature can wildly affect tile from one day to another. The tile expansion joints are necessary for places where the changes every year. The expansion joints are usually available in a couple a different shapes. The purpose of different shapes are different depending on their need, the L-shape joints are typically used for walls and T-shape expansion joints are used between the tile courses. The L-shape is also needed in front of doors, where it helps to reduce the tile from cracking when the door open and closes regularly.
Movement joints are also required at all changes of plane. For example, the corners of an installation, or the transition between stair treads and risers. There is greater stress at these areas and they therefore require the use of a soft movement joint.
Type of Expansion Joint Materials:
Possibly the best type of expansion joint material that can be used is a flexible silicone or urethane sealant placed over a closed cell foam backer rod. The sealant that is used in expansion joints must achieve minimum shore strength of 35 or greater. The two-sided bond allows for highest movement of the sealant. A three-sided bond to the substrate can create a barrier the total capable movement of the flexible sealant and cause early joint cracking and disintegration. Bond breaker tape can be placed in joints that are too shallow to receive the closed cell foam backer rod. This bond breaker tape also makes provision for a two sided sealant bond. In certain cases, a suitable primer should be used in wet area conditions or when using a porous finish material.
Expansion joint strips are also available and can be used in many applications. An advantage to these expansion joint strips is that they protect the exposed tile edge better than the sealants. However, a disadvantage to the strips is that they do not allow for full joint movement as do the sealant joints. Some of these strips are composed of very strong plastic or metal and are not as flexible as the sealant joint. If they are used, it may be a good idea to increase the frequency of placement and/or allow for a wider space when they are placed
Conclusion of tile expansion joint
If you are working on flooring project for your home or any room, where you may think you do not need expansion or there is no space for joints then again you should install an expansion joint. Make a good calculation of everything when you install tile, a good calculation and proper installation will allow you to enjoy your floor for longer years. You can also consult with a tile expert regarding the whole matter to get good suggestions.
In summary, every tile installation should allow for movement. Skillfully and properly designed installations, where expansion and contraction do not create shear forces, should have no problem for the tile to stay well adhered.