How to Enclose a Porch

Learning how to enclose a porch is a great way to get year-round use out of a space that currently only gets used in warm weather. An enclosed porch provides a heated area in cold weather and the ability to open things up when warm weather returns.

How To Enclose A Porch And Create New Living Space

Your existing porch has a floor, a roof and some structural elements (posts) to hold up the roof. Between the structural elements, you probably have some railing for safety. Most of these elements will stay and the addition of walls and windows will create an enclosed space. Here's how to proceed:

• Porch enclosure planning. Typically, a short wall (called a knee wall) and windows that fill the vertical space are used to enclose porches. The windows are installed adjacent to each other, separated by studs or support posts. You'll need to measure your porch, decide on the type and size of windows you'll use. With a window size in hand, you can calculate how many windows and how much material you'll need. Creating a simple layout plan on graph paper will help you keep track of construction details and dimensions.
• Demolition man. The first step is to remove elements that won't be needed. Remove any railing around the perimeter of the porch and trim the floorboards around the edge so that they are flush with the supports (typically a rim-joist) underneath.
• Cut off at the knees. You'll need to build a short wall around the edge of your porch called a knee wall. The knee wall will reduce the size of the windows you'll need. The knee wall also provides support for the windows and a space to install installation and wiring for internal use.
• Constructing the knee wall. The knee wall is installed between your existing porch posts. If your porch doesn't have posts against the walls of the house, you'll need to add them as a support structure for the knee wall ends. The knee wall is easily constructed using two-inch thick dimensional lumber that matches the thickness of your posts. Typically, 2"x6" wood is used to create a top plate, sole plate and 16" on center studs. These framing members are nailed to the existing floor and posts.
• Top of the world. A top plate (also from 2"x6" lumber) should be installed above the knee wall, attached to your porch's existing ceiling joists.
• Got jack? Once the knee wall and top plate are in place, you'll need to install jack studs between the two that will fill in between windows. Using our original layout plan, mark out the location of all windows on the top of the knee wall. You should plan to have two 2"x6" jack studs between each window. The jack studs will provide support and a nailing surface for installing the windows.
• Window work. Following the manufacturers instructions, install the windows using the top plate, jack studs and top of the knee wall as nailing surfaces. Make sure the windows are plumb and square in their openings.
• Electrical considerations. If you require electrical outlets in your enclosed porch, run wiring according to local code through the studs of the knee wall. Once outlet boxes are installed and wire, finish work can begin.
• Finishing up. With the framing, windows and electrical work in place, you can turn to finishing off your porch enclosure. While bead board is a popular interior finish choice, the exterior finish will depend on the finish of your home. Try to match or coordinate the exterior of your porch enclosure with your home's materials and colors.