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Install a Patio Door

Install a Patio Door

If you are longing for a great view of those beautiful green plants and flowers in your back yard, then consider installing a new patio door on your own. You'll love the new view.

Tools & Materials

Use this checklist when you go to the store and purchase your items.


Choosing Your Door

There are some basic principles involved in the installation of preassembled patio doors. Detailed installation instructions will be included with the particular door you choose. Installing a patio door in an existing opening is relatively easy as long as you properly measure the opening before ordering the door. Cutting an exterior wall to install a patio door is more involved and will require that you repair or replace the interior surface of the wall in which the door is placed. Perhaps the biggest step is to overcome the psychological resistance to knocking a big hole in one of your exterior walls.

Several patio door options are available. Choose the style that appeals to you, depending on your situation and preference. Swinging patio doors open like conventional doors, but feature large glass panes for a view of the outside. They may be installed as single, double or triple doors, depending on the size of your door opening, but double door units are most prevalent.

Characteristically, preassembled double door units come with one fixed and one operational door. They are commonly available in wood or steel models.

Bypass (sliding) patio doors are space-saving alternatives to swinging doors. Unlike swinging doors, which require that objects be set well away from the doorway, sliding doors require no room to swing. Sliding patio doors usually have one door that is fixed and another that slides. They often have aluminum frames, although they may be vinyl steel or wood. The aluminum ones are usually the least expensive patio doors.

Either type of door may be characterized as having "right-hand" or "left-hand" operation, as viewed from outside, so you must know which side you would like to operate. Purchase your patio doors with the door panels already installed in preassembled frames. This will greatly simplify your project.



Measure for Your Patio Door

If you are installing a patio door in an existing opening, determine your door's rough opening dimensions before purchasing your new door. In some cases it may be necessary to order a unit based upon the size of the rough opening.

To access the studs and measure for the rough opening, carefully remove the casing from the inside of the existing door opening. Take the measurement from the inside surface of the studs.

Measure horizontally across both the top and bottom of the rough opening, as well as vertically on each side. You may find that the rough opening is not square. When determining what size door you will need, use the smaller of each of your vertical and horizontal measurements. For example, if the left vertical measurement is 83" and the right vertical measurement is 82 3/4-in, use 82 3/4-in for the vertical measurement when determining your rough opening size.

Save the door casing to be reinstalled after the new door is installed and skip to Installation. Some of the steps listed will be unnecessary for your installation.



Prepare Your Wall for a Patio Door

If you are planning to install a patio door in a wall where no opening exists, you have some work to do. Select your door placement carefully. Look for clues that may indicate if there are obstructions in the wall that could cause you problems later. For example, if a vent pipe extends through the roof immediately above the wall area where you want to place the door, you may find after removing the inside wall that the vent passes through your proposed doorway.

After you have determined your door placement and are satisfied that you are unlikely to run into problems within the wall, purchase a door of the type and size you want. The instructions will include information about framing the door, including measurement information concerning the appropriate rough opening size.

This job is going to be messy, so prepare a work space in the area where you plan to install the door. Give yourself plenty of room to work.


Step 1

Remove the inside wall in the area where you want to install the door. You may want to remove the entire wall or you may want to remove just enough of it to allow you to frame the rough opening. A hammer works great for removing drywall. Just knock a hole in it and break it away in pieces. To get a clean break in a straight line, score the line first with a utility knife.

If you plan on removing just part of the wall, locate the studs one bay out from the area where you intend to put the door. Carefully remove the drywall back to these studs and trim it even with the edges of the studs. Later, when you repair the wall around the door, you will nail new studs inside of the existing ones to give you a surface on which to nail or screw the new drywall.


Step 2

Remove any insulation. This will give you a view of the back of the exterior wall.


Step 3

If any electrical wires cross through the doorway, they will have to be rerouted to run outside the perimeter of the doorway. This is not difficult; it is just a matter of extending the wire so you have adequate length. Use the appropriate size and type of wiring for the circuit and splice white to white, black to black and copper to copper colored wire. Just be sure the power is off to the circuit before working with the wires. Also, be aware that codes require that any splices which are made in home electrical wires must be contained in approved electrical boxes. Use wire connectors to make all connections.


Step 4

Frame the rough opening per the manufacturer's instructions for your door. Then, using a circular saw, hammer and chisels, remove the exterior wall from the framed area. Framing the rough opening before removing the exterior siding will delay opening the hole until the last minute. That way, if something comes up and you have to wait until the next day to continue, you do not have an open hole in the side of your house.

You can remove the exterior siding and sheathing by using a circular saw with the blade set deep enough to cut through the sheathing. For areas you cannot reach with the circular saw, such as near the floor, use a handsaw or chisel.


Installing the Door


Step 1

Test fit the patio door in the rough opening. From inside, make any required adjustments and shim as necessary so the door frame is plumb and square.


Step 2

Mark around the perimeter of the door frame brickmoulding. If you have vinyl siding, it will be necessary to add a small amount of extra space outside the line of the brickmould to accommodate the piece of channel trim that will be installed between the brickmould and the siding.


Step 3

Remove the door and carefully cut along the line using a circular saw with the blade set just deep enough to cut through the siding. It may be necessary to use a chisel in the corners and near the ground. Removing the siding in this area will allow the door to sit in a recess against the sheathing and framing. The siding will butt against the side of the brickmould.


Step 4

Cut a piece of drip edge to the width of the rough opening. Using silicone caulk, insert the drip edge along the top of the rough opening, between the siding and the existing building paper.


Step 5

Cut 8 - 10-in wide strips of building paper. Insert the paper between the siding and the existing building paper on the outside wall. Wrap the edges around into the rough opening and staple the building paper in place against the framing studs.


Step 6

Apply silicone caulk around the edges of the rough opening where the siding meets the building paper. Also apply several liberal beads along the bottom of the opening where the threshold will sit.


Step 7

Install the door in the rough opening. Shim the door from inside as necessary to allow the door and frame to sit square and plumb. If there are gaps under the threshold, add additional shims under the door every 6" or so for support. Make sure that you install shims under any screw holes through which the threshold will be attached to the floor to avoid having the screws pull the threshold out of shape. Make the shims snug, but don't force them in place. Forcing the shims could distort the frame and cause a bow along the threshold.


Step 8

Install shims around the edges and top of the door frame. Space them approximately every 12-in. If you are installing a swing style door, use additional shims to support the strikeplate area of the door frame. Make sure everything is level and plumb.


Step 9

Ensuring that the brickmold is flat against the framing lumber from outside, drive 10d finishing nails through the brickmold into the framing every 12-in or so and in the corners. Countersink the heads to facilitate applying the finish later.


Step 10

From inside of the house, drive 10d finishing nails outward through the shims and into the framing. Again, countersink the nail heads.


Step 11

Screw the threshold to the floor.



Finishing Your Patio Door Installation


Step 1

Trim the shims with a handsaw.


Step 2

Wearing appropriate protective clothing and equipment, insert insulation loosely into any gaps between the door frame and the rough opening. Do not stuff the insulation tightly into the cracks. This reduces the effectiveness of the insulation and may distort the door frame. Also install insulation in the area behind which you will be replacing the interior wall.


Step 3

Install sill nosing under the outside threshold.


Step 4

Caulk completely around the exterior door casing. Use a premium quality, paintable silicone caulk.


Step 5

Fill all nail holes and finish the door and frame as soon as possible after it is installed.


Step 6

Repair and finish the interior wall.


Step 7

Install and finish the interior door casing.