Plan the height of your cabinet appropriately. Since most islands will have at least two stools or chairs pulled up to the surface, you may want to think about the seating or stools first. There are two kinds of bar stools with one being much higher than the other. Unless the island will be used primarily for family eating, there really are no hard and fast rules on height. It does not have to match the height of the kitchen cabinet, but often does. If it is not going to match it should be taller in most cases.
Include a ventilation hood overhead to eliminate smoke, steam and cooking odors if your kitchen island is going to have a cooktop. The range hood should extend beyond the cooking area by 3 inches or more on the sides for proper ventilation. Using the correct fan size will ensure that removal happens as intended. Have a fan capacity of about 50 cubic feet per minute (cfm) for each square foot of cooktop area.
Islands can "float" as well. Smaller islands used primarily as an aid in cooking or baking can be fitted with wheels and moved around the kitchen as needed to aid in cooking. Whether you consider a floating island will probably depend on what you have installed on the floor now, or plan to install (a soft wood will be nicked and scratched).
If you have a big island that can accommodate many people, consider using full benches. The benches can be with or without backing to allow for more comfortable seating.
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