How Long for Thinset Grout?

How Long to Leave Thinset Grout

• As a rule of thumb, the experts at Floors Transformed recommend waiting at least 16 hours before putting any pressure on tiles set with regular cementitous thinset, and advise waiting a full day. These figures are based on using 1/4 to 3/8-inch thinset mortar gridded with a square notch trowel.

  Non-cementitous premixed thinset grout -- sold to the amateur market as a convenience product -- typically takes days, and in some conditions can take weeks, to harden. It relies upon dehydration to harden, whereas a cementitous product hardens due to a chemical process.

Factors Effecting Setting Times

• A precise setting time for regular thinset is not quantifiable, due to the many variables involved in a tiling project. Apart from obvious factors such as temperature and ambient atmospheric humidity, some concrete substrates are likely to wick moisture away faster than others, for instance. Always read and fully understand the directions for mixing quantities and both hardening and curing times given by the manufacturer on the packaging of the product you are using.

Variations on the Basic Product

• Numerous variations on regular thinset itself are manufactured, for instance a flexible latex-based thinset should be used for installing ceramic tiles over a wooden substrate, and thinsets blended with acrylic should be used for setting vitrified porcelain tiles. Sanded and unsanded varieties are available for different applications. These all perform in different ways in different situations. Fast-setting thinset is also available, but is only recommended for experienced tilers. Competent amateurs are best using multi-purpose and polymer cementitous thinsets available from home improvement warehouses and the do-it-yourself aisles of department stores.

Hints for Usage

• Choose white thinset for lighter colored tiles, and gray thinset for darker colored tiles. Even with well-matched thinset, follow your project with a wetted toothbrush every few tiles to ensure the joints are entirely clean.