COMPOSITION: All shiplap sheds have high grade premium quality tongue and groove timber throughout including roof and floor – No chipboard or OSB. Our wooden sheds use 12mm extra thick shiplap cladding responsibly sourced in line with our sustainability policy. SECURE WINDOWS: Garden sheds with windows use toughened safety glass as standard - 500% more resistant to heat and shock than ordinary glass. Pre-fitted to our garden sheds to make assembly even easier. DURABILITY: Wooden apex sheds with premium features including heavy duty framing with corner bracing for increased strength, galvanised rust resistant ironmongery, and advanced wood preservative for increased protection. High performance polyester roofing felt which lasts longer on your garden shed. WATERPROOF FELT: This Shed is complete with a waterproof felt with special "polyester" backing ensuring It lasts longer and dosent ripple or tear easily. The felt is saturated with a protective coating called bitumen (Asphalt), which repels water but still allows the product to breathe GALVANISED IRONMONGERY: A Power shed comes with galvanised hinges, turn bottons and door pull so the shed lasts longer and minimises oxidisation. Galvanising is a coat with a protective layer of zinc in order to protect it from rust and other damage.