2024-25_NTCA_Reference_Manual_dig_dwnld

Curing Compounds/Release Agents/Sweeping Compounds – Testing/Letter

TESTING

This page is for the tile contractor's use only!

The water beading test is an effective method of indicating the presence of a curing compound or other contaminating material on a concrete surface. This sim ple test can be effectively performed by the tile installer: Step 1: Thoroughly sweep (clean) surface to be tested. Step 2: Visually survey area to identify potential problem areas. Step 3: Damp clean various areas on the slab and sprinkle with water droplets. If the drop lets of water bead up and do not pene trate the slab within a few minutes, it is likely that the surface is contaminated, and the tile will not adhere.

Date

Company Address City, State Zip

Re: Project Substrate Conditions to Receive a Bonded Tile or Stone Installation.

Contact:

The success of the finished tile installation is directly related to the proper prepara tory work done by other trades.

When tile or stone is to be bonded directly to a concrete slab, the following require ments are necessary: 1. Concrete slab must be sound, crack-free, and fully cured. 2. Concrete slab must be free of dirt, dust, oil, curing compounds, or any coatings that may prevent bond of the tile to the slab. 3. Concrete slabs to receive a thin-set tile installation shall have no variation in plane exceeding 1/4 in. in 10 ft. (6 mm in 3 m). For tiles with at least one edge 15 in. (0.38m), the substrate shall have no variation in plane exceeding 1/8 in. in 10 ft. (3 mm in 3 m). 4. Concrete slabs shall be steel troweled, then light broom finished. 5. Prior to commencing ceramic tile work, the surfaces to receive tile and acces sories will be inspected. The architect or other designated authority will be notified in writing of any defects or conditions that will affect a successful tile installation. Installation work will proceed when satisfactory conditions are provided. Concrete slabs that do not comply with industry requirements may be corrected by the use of the following procedures: 1. The removal of curing compounds, oil or other coatings can be accomplished by bush hammering, sandblasting, shot blasting, water blasting, chipping or scarifying to provide a substrate acceptable to receive tile and stone. 2. Slabs that are out of tolerance for the materials selected can be brought to standard by the use of cement-based flowable mortars or latex trowel-applied underlayments. Gypsum based underlayments are unacceptable without a full release of any liability to the tile/stone installer. 3. The ANSI A108 Standards and Specifications for the Installation of Ceramic Tile require that cracks in the substrate be treated with a crack-isolation mem brane system to help avoid those cracks from telegraphing through the tile installation.

Test Sample Install several pieces of tile randomly in non-traffic areas. Allow to set at least three days, remove them to determine the adhesion to the slab.

Suggestion to the tile contractor: The Curing Compounds, Form Release Agents, and Sweeping Compounds data is separate from Testing data so the tile contractor can copy page 24 and provide information needed by the contractor/builder without disclosing the tile contractor’s test procedure.

Name and Title Company

This document is compiled by the NTCA Technical Committee and published by National Tile Contractors Association, Inc. • P. O. Box 13629 • Jackson, MS 39236 U.S.A. The disclaimer on page 1 and the introductory comments contained in the complete Reference Manual are applicable to copied or excerpted parts.

NTCA Reference Manual | 2024 / 2025

Chapter 2 | Substrates

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