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What Are Egress Windows? Does My Basement Need Them?

What Are Egress Windows? Does My Basement Need Them?

A finished basement can be one of the simplest ways to add additional space to your home. It can be a good area for another bedroom, a family room or a playroom.

As you plan your basement remodeling project, be aware that you may need to add bigger windows. Egress windows, also known as basement windows, are large openings that provide an escape route in an emergency. They can also add natural light and make your basement feel more welcoming.

Egress windows are mandatory for basement bedrooms, regardless of whether your basement is updated. They’re also needed for living spaces in basements that don’t have egress windows. This affects offices, TV rooms, workout rooms and workshops, to note a few.

These windows are an important secondary exit. During an emergency, stairs or an above-ground basement door could be blocked. Egress windows need to be large enough for an average adult—or a firefighter in full gear—to come through.

In short, your finished basement won’t be fully finished until egress window installations are complete.

Windows in Older Basements May Be Too Small

Basements in older homes, especially those made before World War II, were not originally designed to be remodeled into sleeping or living areas. Homeowners at that time used this style of basement for utility space, laundry and storage. Therefore, emergency escape windows weren’t necessary.

If you live in an older home, there’s a good likelihood it has narrow rectangular windows in the basement. Also known as hopper windows, these above-ground windows open inward to provide fresh air. But these windows are small—too small for an adult or fully-geared first responder to climb through.

Basement fires happen regularly, with firefighters handling about 6,500 of them in the U.S. annually. And time is limited to get out when there’s a house fire. It can become fatal in as little as 2 minutes and engulf a home within 5 minutes, according to the National Fire Protection Association.

Requirements for Basement Windows

Building codes require a basement window’s opening to be a particular size. This allows for a speedy exit in an emergency.

According to the International Residential Code, basement windows must have:

  • An opening width of at least 20 inches.
  • An opening height of at least 24 inches.
  • A net clear opening of at least 821 square inches—or 5.7 square feet.
  • A sill no more than 44 inches off the floor.

Not sure if your present basement windows meet today’s requirements? All you need is a tape measure.

  • Open the window completely.
  • Measure the width and height of the opening.
  • Multiply the width by the height.

Is your measurement equivalent to the required 821 square inches—or 5.7 square feet? If not, you need to have bigger windows installed.

If your basement windows are below ground level, you will need to have a well dug at the base of the window frame. This well needs to be at least 36 inches wide and 36 inches long. If the well is more than 44 inches deep, it will need a permanent ladder or steps.

It’s simple to add steps when you use timber or concrete blocks in the well. Plus, you can include several small landscaping features, like crushed rock or potted plants, to increase your curb appeal.

Basement windows can be located under a deck or porch as long as there’s enough room for an average-sized adult to escape. At minimum, there should be 36 inches between the top of the window well and the bottom of the deck or porch joists.

Because basement windows are a way out, they must open from the inside. Any screens, grilles or bars need to be removable from the inside. Both must be accomplished without keys or tools, because time is critical in an emergency.

It’s also essential that basement windows can open entirely. The window sash, or the moveable part of the window that holds the glass, shouldn’t interfere with the opening. This enables your family to quickly exit—or first responders to quickly enter.

Local requirements for basement windows may vary. Check with Boston building officials to learn more about area guidelines.

Choosing a Basement Window

There are several kinds of windows that work well for basements and meet building code requirements.

Casement windows are a good option for homeowners with limited wall space. These windows work like a door, swinging free to provide a wide opening.

Casement windows are opened by rotating a handle. Pella® casement windows use a crank that smartly folds away so it won’t disrupt shades.

The minimum net opening for this type of window is 8 square feet.

Sliding windows are great for homeowners who have a big basement or want increased light. These windows have to be wider and taller because the opening is only half as wide as the window. This is due to the horizontal sliding sash.

Sliding windows are opened by shifting the sash, typically from left to right. Some Pella models include extra-durable tandem nylon rollers, which provide even more effortless operation.

The minimum net opening for this type of window is 16 square feet.

Basement escape windows are a must-have for downstairs living spaces. They can also be a lifesaving device in an emergency. Meet with the professionals at Pella of Boston when you’re planning to remodel your basement. They can help you find the right windows that fit your project, budget and local egress requirements.

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