Rect.height

Description

The height of the rectangle, measured from the Y position.

Setting this value will also change yMax.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    public Rect rect = new Rect(0, 0, 10, 10);
    void Example() {
        print(rect.height);
        rect.height = 20;
    }
}