A somewhat US biased article on library ladders used for kitchens but interesting none the less. We have not done many library ladders but the request comes from time to time. The highest cabinets we have made were over 3.5m tall.
Where there are appliances, care must be taken to make sure there is sufficient ventilation. Often there are limitations to cabinet material lengths and access restrictions and so we have to make cabinets on top of other cabinets which can increase the costs but do open up access to space usually lost.
http://remodelista.com/posts/design-sleuth-library-ladders-in-the-kitchen