How thick are porcelain slabs for shower walls?

Porcelain slabs for shower walls run from 6mm to 12mm thick. Six millimeter slabs are the lightweight option for walls only — they cut easily and bond well to a tile-backer substrate. Twelve millimeter slabs are the standard for most shower work, and they handle benches, niches, and curbs without flex. Twenty millimeter porcelain exists but rarely shows up in shower-wall jobs because the weight gets unwieldy on vertical surfaces. Brand specifics: Laminam offers 5mm, 12mm, and 20mm. Neolith runs 6mm and 12mm. Xtone and Dekton typically come in 12mm for walls. We pick the thickness based on the substrate, the format, and whether you want a wrapped curb or bench. The right thickness gives you a shower that lasts decades. The wrong call shows up as flex or hairline seam cracks within a few years.