Grade A teak garden bench left outside in a frosty UK garden, showing natural weather resistance Yes, you can leave Grade A teak furniture outside in the British winter.  Unlike other woods, teak is naturally saturated with oils and rubber that act as a waterproof barrier. It will not warp, rot, or become brittle in freezing temperatures. However, it will naturally weather to a silver-grey colour if left untreated. If you have just invested in a premium teak dining set , the