DIY Window Well

Excavation

• Shovel out the hole or use a backhoe to create the necessary opening. The well must be centered across the window. Refer to the instructions for direction on the dimension of the hole. Generally, a standard-sized basement window consisting of 5 square feet requires about a 4-foot wide opening that protrudes, at minimum, 36-inches from the foundation wall. Dig the depth of the hole a maximum of 44-inches from the floor of the well to the surface of the soil. The depth should be 6 to 7 inches below the window sill.

  If the well is deeper than 44-inches, and the window will be used for egress, install a step. Concrete blocks can be used to form the step, but make sure that the window will not be blocked. Another option is to install a ladder.

Install the Window

• Cut the rough opening for the window .25 to .50 inches wider than the outside dimensions for the window or per the product instructions. For example, the window guidelines may require you to install 2-inch by 8-inch pressure-treated framing around the opening, so you will have to incorporate the thickness of the boards into your measurements. Use a concrete demolition saw when cutting into a masonry wall.

  Make sure that you wear eye protection and cover up because the saw will create a huge amount of dust. Also, you may need to install a steel lentil at the top of the cavity, which provides support for the wall section above the opening for wider windows or if there are floor joists perpendicular to the space. Make sure that the window is level and straight. Use wood shims as necessary before securing the window in place.

Install the Drain & Floor

• To ensure that rain water drains properly, use 6-inch pipe to tap into the foundation drain system to provide adequate drainage for the well. Cover the drain pipe with about 12-inches of .50-inch diameter rocks. Place about 3 inches of course rocks along the foundation wall and slope the rocks toward the window well 1 inch per foot.

Setting the Window Well

• Center the window well about 3 inches above the soil. The bottom of the well should be about 8 inches below the window sill, but at least 2 inches off the floor of the well. Secure flanges of the well to the foundation wall with the appropriate fasteners. Drill the pilot hole for the fasteners. When mounting to a masonry wall, install the fasteners in the mortar joints when possible.This will prevent splitting the bricks or concrete blocks.