100+ Free ACT Grouts Practice Questions

No. ACT Grouts and ACT Membranes are the two ACT disciplines that do NOT require Certified Tile Installer (CTI) or BAC Journeyman status, because they are traditionally finisher disciplines. The other seven ACT modules (mud floors, mud walls, shower receptors, gauged porcelain tile panels, large format tile, exterior, and stone) still require CTI as the prerequisite. To register for ACT Grouts, you must complete the ACT 100-Level Foundations Series and schedule through the ACT Consortium.

ANSI A118.6 — Standard Cement Grouts (Portland cement + dispersible polymer powder, baseline performance, prone to efflorescence). ANSI A118.7 — High-Performance Cement Grouts (calcium aluminate cement + polymer; better stain, color, abrasion, and chemical resistance, less efflorescence; about 2× the cost of A118.6). ANSI A118.3 — Chemical-Resistant, Water-Cleanable Tile-Setting and Grouting Epoxy (100% solids, virtually waterproof, used in commercial kitchens and labs). ANSI A118.10F — Urethane Reaction-Resin Grout (single-component or two-part, flexible, stain-resistant). ANSI A118.19 / A108.22 — Organic Premixed (single-component) Grouts (ready-to-use, polymer-based, no field mixing).

TCNA recommends a minimum 1/8 inch grout joint for rectified tile, including rectified large-format porcelain. For calibrated tile (tiles with natural manufacturing variation in size), the minimum jumps to 3/16 inch. The joint width also drives the grout choice: joints under 1/8 inch should use unsanded cement grout, while joints 1/8 inch and wider should use sanded cement grout — sand reinforces wider joints against shrinkage cracking and provides necessary aggregate. Joints smaller than 1/16 inch are not recommended because they cannot be reliably filled with cementitious grout.

Slake time is a 5-10 minute rest period after the initial mix and before remixing the grout. During slaking, water finishes penetrating the powder, the polymers begin to activate, and the mix reaches its final working consistency. Skipping slake produces a weaker, more crack-prone grout. After slake, the grout will feel stiffer — DO NOT add more water (re-tempering). Instead, remix by hand or with a slow drill to restore plasticity. Adding water after slaking dilutes the polymer binder and significantly weakens the cured joint.

Use a hard rubber grout float and work in small (10-25 sq ft) sections. Spread grout across the tile face working DIAGONALLY to the joints — this packs grout fully into the joints without pulling it back out. Hold the float at a 30-45° angle to apply, then at 70-90° (close to vertical) to strike off excess. Always work from the far side of the area back toward the exit so you don't step on freshly grouted tile. Make a final diagonal pass to clear excess grout from the tile face before starting cleanup at the thumbprint stage.

Thumbprint stage typically arrives 15-30 minutes after grouting (faster in hot/dry conditions). Press a thumb on a joint: if it leaves a clean print but no grout sticks to your finger, it is ready for initial cleanup. Use the 2-bucket method: one bucket of clean water, one for rinse. Wring the sponge until it is nearly dry, then wipe the tile face in straight diagonal passes — never along the joint. Change rinse water as soon as it clouds. After the surface dries, a haze remains; buff it off with a dry microfiber cloth. Avoid flooding the joints with water — overwashing weakens the grout.

No. ANSI A118.3 epoxy grouts and A118.10F urethane reaction-resin grouts are essentially non-porous and stain-resistant by design, so they do NOT require any post-installation sealer. Cement grouts (A118.6 standard or A118.7 high-performance) are porous and DO benefit from a penetrating sealer, applied after the grout has cured for 48-72 hours and reached the bulk of its 7-28 day full cure. Penetrating sealers fill the pores so the grout still breathes — topical/membrane sealers are not recommended on freshly installed cement grout.

EJ171 requires soft-joint sealant (NOT grout) at: every perimeter where tilework abuts a restraining surface (walls, columns, curbs, dissimilar floor finishes), every change of plane (wall-to-floor inside corners, wall-to-wall inside corners, ceiling transitions), every structural/expansion/control joint, at field locations every 20-25 ft for interior and every 8-12 ft for exterior installations. Joints must be at least 1/8 inch wide and filled with an ASTM C920 sealant — typically a color-matched sanded or silicone caulk supplied by the same grout manufacturer to match the grout color.