When you are looking at stair, what tells you that it is modern? Of course, this is a taste which was put into its design. It is very nice when a house owner addresses a professional and their ideas are combined. But we are still sure that everything what is new looks modern. Though, when you want to have modern spiral staircase, you should choose materials carefully. Staircase must be a masterpiece, an elegant item of your house. When you are stepping on the first step, you should feel as if floating above the clouds. This is why modern spiral staircase designs are usually well-thought.
Staircase made of glass or having glassy elements always looks modern. Moreover, you can use glass to build walls near the spiral staircase. As for more interesting ideas, there is a chance to create vision of a snake. You could achieve it painting the steps with bright or shining color. Thus, your spiral stair will resemble a twining cobra.
Think of the size and shape of the steps. They can get narrowed to one side in order to make staircase look unusually. Such steps can be made of wood or glass. Wooden stair brings some classic to the look of a house, and glass is always an object of admiration for guests, especially if some steel items are present as decoration or functional elements.