WHOA. The new King Electric SCM Snow Melt Mats have an INCREDIBLE number of sizes to choose from. Almost 200 sizes from 2 foot x 4.4 foot up to 3 foot x 59.4 foot (that’s 6.4kW covering 178.3 sq.ft.!)
https://morelectricheating.com/products/MANUFACTURERS/KING%20ELECTRIC/SCM.aspx