STEEL INTERLOCK SHEDS, GARAGES ,STABLES, & AMERICAN BARNS Steel Interlock Sheds offer easy to assemble steel buildings, ranging from garages to light commercial and agricultural sheds. S.I.S products combine the strength of steel with a patented 'SLIP-FIT' design that makes assembly straight forward, saving you time and money. Our frames have a patented 'TRIPLE-COAT' sealing process and come with a 20 year guarantee. Steel Interlock buildings are relocatable and extendable, perfect for temporary storage and warehousing. Order a component pack and do it yourself or get a complete construction package. Simply call 0800 777 717 for a no-obligation quote