Generally, you should apply preservative treatment to a Log Cabin as soon as you can and preferably within a week of building. The timbers arrive untreated to make it easier for you assemble. A year after the initial coating it is a good idea to reapply treatment, then you need to repeat every year or two, depending on the weather and condition of the timbers. It is best to apply protective timber treatments during Spring or early Autumn, whilst the weather is dry.
Ideally, we recommend that you apply a protective coating one year after assembling your shed and then repeat every year or two depending on the weather conditions. It's best to apply the coatings on a dry day in Spring or Autumn.
The beauty of buying a pressure treated shed is that you do not need to apply any preservative treatment. That said the wood will still change colour over the years, to keep your shed looking fresh you may wish to apply a timber treatment every 4-5 years.