People often use the phrase, “They don’t make them like they used to,†referring to things that fail to last or perform well. Considering the cracks in tile floors installed only a few years ago, the remark certainly seems to apply. After all, there are buildings with tile floors that remain intact after centuries. Why can’t modern tile floors last like that?
Some of them can. Modern underlayment for tile flooring is using an old idea in a new way to produce tile flooring that resists cracking “like they used to.†An example is Schluter Systems’ Ditra underlayment offered at www.southshoreflooring.com.
Most people assume that cracking of a tile floor results from thousands of footsteps. This may be true in a minority of cases, but in far more, the cause is shifting of the surface under the tiles. Even the best structures experience some settling over time, and the surrounding soil can shift from water movement or geological activity.
Recognizing that this shifting was inevitable, the tile setters in ancient times found a way around the problem. Instead of laying tile directly on the substrate, they poured a layer of sand and put tile on that. The sand provided a pliant shock absorber so substrate movement would not be transferred to the tile.
Due to cost and time constraints, this technique is no longer used for homebuilding. Instead, a layer of pliant underlayment is unrolled and cemented in place, providing the same function with less work and expense.