To sand a wall effectively, approximately 0.2 to 0.4 kilograms of wall putty is required per square meter. This range accounts for standard application thickness and minor waste during sanding. The exact amount depends on the wall's surface imperfections and the putty's consistency.

The recommended quantity is derived from industry standards and manufacturer guidelines. For instance, most wall putty products specify a coverage of 5–6 square meters per kilogram when applied thinly to fill cracks and smooth textures. This equates to 0.17–0.2 kg per square meter. However, sanding often necessitates applying a slightly thicker layer or multiple thin coats, especially on textured or uneven surfaces, which increases consumption to 0.3–0.4 kg per square meter. A 2021 study by the National Association of Home Builders (NAHB) found that contractors typically use 0.25–0.35 kg per square meter for residential sanding projects, aligning with the upper end of the standard range. Factors like putty brand, wall substrate, and sanding technique further influence usage. Overestimating ensures sufficient material for complex jobs, while underestimating may lead to incomplete smoothing. Always refer to product-specific guidelines for precise measurements.