Background This product-specific plant-specific declaration was created by collecting production and supply chain data for Coldspring's manufacturing facility in Marble Falls, TX. Upstream data for stone quarrying operations was adopted from Natural Stone Institute’s (NSI) industry-wide stone cladding LCA published in November 2022. All unit processes were modeled using primary data. Secondary data sources include those available in the ecoinvent v3.10, US-EI 2.2, and Industry data 2.0 databases.

Allocation Since manufacturing resources other than electricity were used across all types of StoneLite® panels, and not dedicated solely to specific panel types, they were evenly distributed based on production area. The annual manufacturing resource use was calculated relative to the annual production area and further weighted according to each year’s production levels, providing a comprehensive, area-based annual resource allocation. Electricity measurement varied due to specific equipment requirements, and porcelain processing was estimated to need approximately 15% less electricity than stone-based processing. The total amount of electricity consumed each year was therefore calculated separately for natural stone panels and porcelain panels. No recycled materials are used in the product system, and there were no co-products manufactured.

Cut-off criteria for the inclusion of mass and energy flows are 1% of renewable primary resource (energy) usage, 1% nonrenewable primary resource (energy) usage, 1% of the total mass input of that unit process, and 1% of environmental impacts. The total of neglected input flows per module does not exceed 5% of energy usage, mass, and environmental impacts. The only exceptions to these criteria are substances with hazardous and toxic properties, which must be listed even when the given process unit is under the cut-off criterion of 1% of the total mass.

In the absence of suitable proxy data sets, some ingredients making up the epoxies and bonding putties were excluded; however, the cumulative mass of excluded ingredients is less than 1% of the product system. No known energy flow has been omitted in this study, and the excluded ingredients are expected to have an insignificant effect on environmental impacts.

All known hazardous wastes released from the manufacturing facility have been included in this study, including methyl ethyl ketone which is used for cleaning purposes and is not a part of the final product. No carbonation or calcination is expected to occur during the production and manufacture of the panels. Biogenic carbon is included in reported results.

Quality Temporal and technological representativeness are considered to be high. Geographical representativeness is considered to be high. All relevant process steps for the product system were considered and modeled. The process chain is considered sufficiently complete with regards to the goal and scope of this study.

The product system was checked for mass balance and completeness of the inventory. Capital goods were excluded since they are assumed not to significantly affect the conclusions of the LCA. Otherwise, no data were knowingly omitted. For more information on data quality, see the LCA background report.

Flow diagram

Major system boundary exclusions

• Construction of major capital equipment
• Maintenance of operation and support equipment
• Human labor and employee transport
• Manufacture and transport of packaging not associated with final product
  
• Building operational energy and water use not associated with final product

Major assumptions and limitations

• It was estimated that porcelain panels consume 15% less electricity than natural stone panels; however, slight deviations are possible
• Generic data sets used for material inputs, transport, and waste processing are considered good quality, but actual impacts from material suppliers, transport carriers, and local waste processing may vary
• The impact assessment methodology categories do not represent all possible environmental impact categories
• Characterization factors used within the impact assessment methodology may contain varying levels of uncertainty
• LCA results are relative expressions and do not predict impacts on category endpoints, the exceeding of thresholds, safety margins or risks