Several factors determine the shape and the size of a kitchen island, including the size and shape of your kitchen and the functions you need the island to perform. For example, you should decide whether you want the island to have a seating area, or whether it is going to be solely a work space. Be sure to include countertops at different heights so all your family members can gather around this space.
Regular shaped kitchen islands are usually built-ins, constructed as one unit. The basic regular shape is a long, straight unit, suitable for narrow kitchens. An L-shaped island fits into a large rectangular or L-shaped kitchen and can separate the cooking and eating areas of the countertop. Adding another leg at the junction turns this form into a T-shaped island, which is effectively two straight islands at right angles to each other. The length of the cross part of the "T" can vary depending on the size of the kitchen, from a short work space to a longer countertop that houses a sink or an appliance.
Around the Bend
If your kitchen is an irregular shape, you probably need a nonstandard island shape. You may choose to have one custom-made to your own design, or you could use a selection of free-standing furniture put together into an arrangement that fits. The dogleg kitchen island -- a long countertop with an angled unit at one end -- fits into most awkwardly shaped kitchens. While this arrangement has some difficult-to-use space in the angled corner, that challenge is offset by the length of usable space.
Room for Tiers
What you want to do at your kitchen island determines how many tiers you'll need it to have. A single-tier island is usually 36 inches tall and is mainly just a work space. A two-tier island usually has a second, higher, countertop at 42 inches that blocks the view of the lower tier and acts as an eating space for adults seated on bar stools. Don’t forget the kids, though -- consider installing a second or even a third tier at a lower height to make a table for eating and for homework, just for them.
Calculate the size of your kitchen island by factoring in minimum depth and considering how much clearance it will require from other elements in the room. The standard depth of a kitchen cupboard is 24 inches, so your kitchen island will be at least this deep. For comfortable and safe working in the kitchen, allow an aisle of 36 to 48 inches all around the island. Make sure to provide this clearance between the island and an appliance, a wall or another cabinet. If you’re using the island as a cooking space, experts recommend allowing for 36 inches of continuous countertop for each cook. When your guests are seated at the island, they'll need 24 inches of counter space each, so they don’t bump elbows with one another.