If you're interested in timber cladding, take a look at this piece of research from the Scottish Excecutive. It's a study outlining the development of timber cladding in Scotland, describes timber clad buildings in Scotland, and provides practical information on the use of timber cladding in Scotland. As well as lots of useful information (Western red cedar should be avoided in situations where there is a risk of impact damage or vandalism) there are some great pictures, particularly in the case studies section. Here's what they have to say about garden office sheds:
"Poorly-designed, or maintained, temporary buildings such as stables, garden sheds and garages have tarnished the reputation of timber cladding. Design is driven by large DIY merchants and some specialist suppliers and, in this price-sensitive market, ongoing maintenance is virtually unheard of. In this sector better-designed timber-clad buildings are exceptionally seen and it may be that a niche market can be created. The recent growth of garden office structures are an example of this type of more up-market temporary building. European whitewood is the most common cladding timber, with western red cedar being used for more up-market structures."