STONE –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– saunas, steam rooms, swimming pools, hot tubs, and exterior areas. 3.7.2 Self Leveling Underlayments. Gypsum-based and self-leveling under- layments are not recommended for use with stone paving, except in conjunc- tion with an approved water-proofing/ crack isolation membrane(See ANSI A118.10-118.12). If using this meth- od, extreme caution in following the Manufacturer’s recommended proce- dure is required. 3.7.2.1 Installation of stone paving directly over gypsum based underlay- ment is not recommended. 3.8 Deflection of Surfaces 3.8.1 General Contractor Responsibility. It is the responsibility of the General Contractor to provide a rigid, code-compliant structure that is adequate to accommodate the stone and its anchorage including all associ- ated loads and forces. 3.8.2 Cast-in-Place Concrete Floors. Design substrate for total load deflec- tion not exceeding L/360, as measured between control or expansion joints. 3.8.3 Frame Construction. The sub- floor areas over which stone tile is to be applied must be designed to have a deflection not exceeding L/720 of the span. In calculating load, the weight of the stone and setting bed must be considered. 3.8.3.1 Strongbacks, cross-bridging or other reinforcement shall be used to limit differential deflection between adjacent framing members. 3.8.4 Maximum variation of a concrete slab or subfloor shall not exceed 1/8” in 10’ from the required plane when thin set systems are applied. 3.8.5 Allowance should be made for live load and impact, as well as all dead load, including weight of stone and setting bed. 3.8.5.1 Mortar Bed Weight. For esti- mating purposes, mortar bed weight can be approximated as 0.75 lb. per square foot per each 1/16” of thickness. 3.8.5.2 Stone Weight. For estimating purposes, stone weight can be approxi- mated as 1 lb. per square foot per each 1/16” of thickness. 4.0 SAMPLES 4.1 The Dimension Stone Contractor shall furnish samples of the various dimension stones to be used. Samples shall indicate the extremes of color, veining, and marking the stone sup- plied to the project will have. Samples must be approved or rejected in their entirety, without stipulation. 4.2 Pending the scope of the instal- lation and the variability of the stone product, a full-sized mockup may be required to adequately demonstrate the range of the material’s color and character. 4.3 Inspection of supplied material to evaluate compliance with approved samples shall be done at a viewing dis- tance of not less than 6’-0” with natural lighting. 5.0 CARVING 5.1 All carving called for shall be per- formed by skilled workmen in strict accordance with approved full-size details or models. Architectural draw- ings will show approximate depth and relief of carving. Carving shall be left as it comes from the tool, unless otherwise specified. 6.0 FIELD REPAIR 6.1 During the progress of construction, changes are often 86 TileLetter | May 2018