Basement Egress Window Requirements in Utah

Every basement bedroom in Utah needs an egress window. Period. It’s not optional, it’s not a suggestion — it’s building code. The reason is straightforward: in a fire, people sleeping in the basement need a way out that doesn’t involve the stairs.

Here’s exactly what the code requires and what it costs.

Utah Egress Window Code Requirements

Utah follows the International Residential Code (IRC) Section R310, with state amendments. The requirements apply to every sleeping room and habitable space in the basement.

Minimum Window Opening Size

• Minimum net clear opening area: 5.7 square feet
• Minimum net clear opening height: 24 inches
• Minimum net clear opening width: 20 inches
• Maximum sill height: 44 inches from the finished floor

“Net clear opening” means the actual space you can climb through when the window is fully open — not the window frame size, not the glass size. The opening when the window is operated at its widest.

What This Means in Practice

A window with a 24″ × 34.3″ clear opening meets the 5.7 sq ft requirement (24 × 34.3 = 823 sq in ÷ 144 = 5.7 sq ft). But most contractors install windows larger than minimum — a 36″ × 24″ opening is more common and easier to escape through.

Window Types That Work

• Casement windows — Crank open fully, providing the largest clear opening relative to frame size. The most popular choice for egress
• Sliding windows — Only half the window opens, so the window must be twice the required opening width
• Double-hung windows — Only the bottom sash opens for egress. Must meet minimums with just the bottom opening
• In-swing/out-swing hopper — Can work if they meet the dimensional requirements when open

Don’t work: Fixed (non-opening) windows, awning windows that don’t open wide enough, or windows that require tools to open.

Window Well Requirements

If the egress window is below grade (which it usually is in a basement), you need a window well.

Window Well Dimensions

• Width: At least as wide as the window, plus enough room to maneuver (36″ minimum is typical)
• Depth (projection from wall): 36 inches minimum from the foundation wall
• If well depth exceeds 44 inches: A permanent ladder or steps are required
• Steps must be at least 12″ wide and project at least 3″ from the wall
• Spacing between steps: 18″ maximum

Window Well Cover

Not explicitly required by code in all Utah jurisdictions, but strongly recommended:
– Must be operable from inside without tools
– Must support at least 200 lbs (some local codes require more)
– Must not obstruct the egress opening
– Polycarbonate covers allow light while keeping out snow and debris

Drainage

The window well needs drainage to prevent water accumulation:
– Gravel base (4-6 inches of clean gravel at the bottom)
– Connected to the foundation’s perimeter drain system, or
– A dedicated drain line to a sump pump or daylight

Water in a window well will eventually find its way into your basement. In Utah, spring snowmelt is the primary concern — proper drainage prevents seasonal flooding.

Where Egress Windows Are Required

Required

• Every sleeping room (bedroom) in the basement
• Habitable spaces in basements without two separate exits (some interpretations)
• Any room marketed or used as a bedroom

Not Required

• Open basement areas that are not bedrooms
• Bathrooms, laundry rooms, storage rooms
• Home offices (unless also used as a sleeping room)
• Rooms that have direct access to the exterior (walkout basements with a door)

The “Bedroom” Question

If a room has a closet and a door, appraisers and inspectors will assume it’s a bedroom — and it needs egress. Even if you call it a “bonus room” or “den” on your floor plan, if it looks like a bedroom and could be used as one, local inspectors may require egress.

Pro tip: If you don’t want to install an egress window, design the room without a closet and with a wider-than-standard doorway. This makes it clearly not a bedroom. But honestly, egress windows add light and value — they’re worth installing regardless.

Installation Process

Step 1: Mark and Plan (1 day)

Determine the window location from inside and outside. Avoid utility lines, structural elements, and landscaping features. Check for any underground utilities with a Blue Stakes call (811).

Step 2: Excavate (1 day)

Dig the window well area from outside. In Utah’s clay-heavy soil in many areas, this requires heavy equipment for most jobs. Depth depends on your basement floor level relative to grade.

Step 3: Cut the Foundation (1 day)

Concrete cutting with a diamond blade saw. This is loud, dusty, and requires professional equipment. The opening is cut slightly larger than the window frame to allow for installation and waterproofing.

Step 4: Install the Window (1 day)

Set the window frame, level, and seal. Waterproof membrane around the entire perimeter — this is where most DIY egress installs fail. Improper waterproofing leads to leaks within the first year.

Step 5: Install the Window Well (1 day)

Set the well (corrugated metal, prefabricated plastic, or poured concrete/stone). Backfill around the well, grade the surrounding soil away from the well, and install gravel drainage at the bottom.

Step 6: Finish Interior (1-2 days)

Frame around the window opening, insulate, install interior trim, and drywall. Finish to match the rest of the basement.

Total timeline: 3-5 days for a complete egress window installation.

Egress Window Costs in Utah

Costs vary based on:
– Soil conditions — Rocky soil costs more to excavate
– Depth — Deeper wells (for deeper basements) cost more
– Window size — Larger windows improve light but cost more
– Well material — Basic corrugated steel vs. decorative stone veneer
– Access — Tight side yards increase labor difficulty

Common Mistakes

1. Measuring the Window, Not the Opening

The window frame might be 36″×24″, but the net clear opening when the window is operated is smaller. Always measure the actual escape opening.

2. Sill Height Too High

The bottom of the egress opening must be within 44 inches of the finished floor. If your window is set in the top of the foundation wall and your floor is concrete, you may be fine. But if you add 2 inches of flooring, that sill height changes. Measure from the finished floor level, not the concrete.

3. No Window Well Drainage

A window well without drainage fills with water during rain or snowmelt. It’s a pool against your foundation wall. In Utah, this is especially critical during March-May snowmelt season.

4. Well Cover That Doesn’t Open From Inside

Security-focused covers that lock from outside are dangerous. The whole point of egress is that someone inside can escape. Covers must be operable from inside without keys, tools, or special knowledge.

5. DIY Concrete Cutting

Cutting a foundation wall is structural work. Cut in the wrong place or without proper support, and you can compromise your foundation’s integrity. This is the one step that absolutely requires a professional.

Egress Windows Beyond Code Compliance

Beyond meeting code, egress windows dramatically improve basement livability:

• Natural light — Transforms dark bedrooms into bright, comfortable rooms
• Ventilation — Fresh air circulation that small basement windows can’t provide
• Home value — A bedroom with egress is a legal bedroom. Without it, appraisers won’t count it
• Rental potential — Required for any legal basement rental unit
• Curb appeal — Properly finished window wells with landscaping look intentional, not like an afterthought

Many homeowners who install egress windows for code compliance say the improved light alone was worth the investment.

Utah-Specific Considerations

Soil Types

• Clay soil (common in valley floors): Holds water, requires robust drainage. May need deeper gravel beds
• Sandy soil (common in bench areas): Drains well naturally but may require more structural support for window wells
• Rocky soil (common along the mountains): Excavation is harder and costs more

Frost Line

Utah’s frost line varies from 30-48 inches depending on location and elevation. Window well footings should extend below the frost line to prevent heaving.

Snow Load

Window well covers in Utah must handle significant snow loads. A cover rated for 200 lbs is minimum — consider 400 lb ratings for areas with heavy snowfall.

Ready to Install?

Egress windows are one of the most impactful upgrades you can make to a basement. They’re required for bedrooms, but the light and air they bring improve every room nearby.

Our team installs egress windows as part of complete basement finishes or as standalone projects. Get a free quote or call 801-515-3473.