Ronseal 5 year woodstain is independently guaranteed by the bba to waterproof and protect your exterior wood for a full 5 years the easy to apply woodstain has been specially developed to give ultimate protection against all types of weather it keeps the wood dry by preventing excess water from entering the wood whilst allowing moisture inside the wood to evaporate to prevent cracking peeling blistering and surface mould growth rainproof in one hour suitable for bare or previously stained wood a