Do rubber tiles and rubber mats change dimensions with heat, moisture and ageing?
Rubber tiles and rubber mats can undergo slight dimensional changes as a result of heat, moisture and ageing. Temperature has the greatest short-term effect on dimensions: tiles expand in warm conditions and contract again as they cool, so this temperature-related dimensional change is largely reversible.
With porous tiles, moisture initially increases the weight, and water may remain within the pore structure. The rubber compound and binder can also absorb small quantities of water, which may cause a slight temporary dimensional change. This largely recedes during drying.
After drying, ageing of the material bond can lead to slight permanent shrinkage over time. With a comparable product construction, ageing shrinkage is lower with EPDM granulate than with ELT granulate from end-of-life tyres.
The extent of dimensional change depends on the material composition, compaction, binder, tile geometry and ambient conditions. On installed areas, small dimensional changes can accumulate across several tiles and become visible at edges or joints.
Before installation, all tiles should be at approximately the same temperature and should not have been heated by direct sunlight. Dimensional tolerances stated in the Product data sheet apply to the measurement conditions defined there. They do not represent an upper limit for thermal expansion.