Patio Door Series Part 1: What to Consider Before Choosing a New Patio Door

Jim Coshow smiling.

"We recommend products with a resilient exterior finish, like metal or fiberglass, for most applications."

- Jim Coshow


Welcome to our four-part patio door series, where we’ll break down everything you need to know about patio doors—from selection to installation. In this first installment, specialty window and door sales manager Keith Church discusses how to choose the patio door that’s right for you.

Replacing a patio door can be a lot of work, and choosing the right door is a big decision. Not only do you need to consider how the door functions and fits in your space, but also how it will stand up to weather. In this first installment of our four-part patio door series, I’m sharing insights on what to consider before you decide which kind of patio door is best for you, your needs, and your home.

Weather exposure

When choosing a replacement door, first assess the severity of the weather exposure at the door’s location. Ask yourself these questions:

  • What is the exposure?
  • Is the area under full or partial cover?
  • Will it be exposed to full sun, heavy rain, or severe weather?

For example, if you have a pair of all-wood doors that have failed and need replacing, it would be unwise to purchase another pair of wood doors without expecting a similar outcome. We recommend products with a resilient exterior finish, like metal or fiberglass, for most applications.

Wood doors are far less likely to fail when in a protected and covered area. Wood door manufacturers have a warranty on their products, but they require the end user to apply and maintain an appropriate finish. If an all-wood product has failed and needs replacing, it’s important to evaluate why the finish didn’t adequately protect the door. Was the exterior finish improperly applied or not maintained, or did it fail because the location of the door had little to no protection from severe weather and sun?

If you have an aluminum sliding door that needs to be replaced because it’s old and doesn’t slide well, it's likely you’re not replacing it due to damage caused by sun or rain. If the area is well-protected, you could replace it with any type of door. If the area is exposed to significant sun and weather, it would be unwise to select an all-wood product and expect it to hold up as well as an aluminum sliding door.

Wooden patio with blue double doors leading to the house.

A good way to protect your door from the elements is with an overhang. Use the calculator below to determine the best measurements for your doorway.

Diagram titled "APPROPRIATE OVERHANG CALCULATION." Text at top reads: "Adequate overhang is very critical to the life and performance of a wood stile and rail door. A proper overhang will help protect your door from the elements and extend the life of the door. In most climate conditions the following formula can be used to determine the appropriate amount of overhang: X=1/2Y (where X is the length of the overhang required and Y is the distance from the bottom of the door to the base of the overhang.) For example, if the measurement from the bottom of the door to the base of the overhang is 8 feet, then the required overhang is 4 feet. For more severe climates, very wet or dry areas, the following formula should be used: Y=X." Under the text is a diagram marked with Y (the distance between the bottom of the door to the base of the overhang) and X (the distance from the edge of the overhang to the exterior wall).

Inswing vs. outswing

Patio doors are primarily inswing (opening into the room) for many reasons. One concern used to be the fear of being snowed in, but we don’t have to worry too much about that here in Seattle. I started selling doors and windows almost 40 years ago, when most door companies didn’t have a sill system designed for outswing doors (opening away from the room). Manufacturers would gladly sell you an outswing door but advise you to never allow it direct exposure to rain, or else it would leak into the home—and they had no warranty for leaking.

Fortunately, this has since changed. Whether you’re buying a high-quality metal-clad product or an all-wood door, you’ll receive a sill that’s weather-tight. Newer designed sills for outswing doors often perform slightly better than inswing doors during pressure and water tests. The more the wind blows against outswing doors, the more it pushes them against the weather stripping, so there are no issues with their ability to seal well.

Another aspect to consider regarding outswing versus inswing is your furniture layout. Furniture can be positioned differently if the door doesn’t swing into the house. However, keep in mind that the door panels will swing outside when open, so you’ll need to consider your outdoor furniture, as well. Another thing to keep in mind is that if it rains and the area is not covered, the tops of the door panels will get wet. And you should always install a doorstop for outswing doors to ensure even a small breeze doesn’t slam the door against the house or frame.

Large stone patio of building with glass walls facing outdoor area, with dark wood framed glass patio doors.

To screen or not to screen

Some manufacturers of hinged patio doors offer screening options for inswing but not outswing doors. For inswing doors, you can also install hinged, aluminum screened doors that mount on the exterior and swing out. You may prefer to contact an independent screen supplier that can provide a retracting screen system so you don’t have to look through a screen unless the doors are open.

For outswing doors, manufacturers do not offer an inswing pair of hinged screens. A retracting screen can be installed by an independent supplier—but keep in mind you will see the canister and track system on the inside, and concealing it is difficult.

Clear opening height

One final thing to consider when replacing a patio door is the net clear opening height of the new door. If the rough opening of your door is framed at 80” instead of 82”, you may need to order a retrofit-sized replacement door. If you replace a sliding glass door with a retrofit-sized swinging patio door, it may feel short as you walk through it. We recommend gathering measurements and comparing them to your current door before placing an order for a new one.

Now that you know what to consider in choosing a patio door, stay tuned for the rest of this four-part series, where we’ll go over more tips for purchase and installation. In the meantime, read up on how to know when to replace your patio doors, placing pocket doors, and installing prefit doors.