Egress Window Installation — Madison & Dane County, WI
An egress window is a basement or ground-floor window built and installed to meet specific dimension and access rules so it can double as an emergency exit and a way for rescue personnel to get in. It comes up most often when a basement is being finished into a bedroom, since Wisconsin's building code ties bedroom use directly to having a second way out. This page covers what the Wisconsin Uniform Dwelling Code (UDC) actually requires — not the figures that get repeated on national sites that are quoting a different code — and what an installation involves from planning through the finished opening.
Why a Basement Bedroom Needs One
Wisconsin's code requires at least two exits from any basement or ground-floor area used for sleeping (SPS 321.03(5)(b)1.). For a bedroom, the second of those two exits has to be a code-compliant egress window that meets the dimension rules under sub. (6) of that same code section (SPS 321.03(5)(b)4.d.). A regular basement window installed for light and ventilation doesn't satisfy this rule on its own — it has to meet the specific size, sill-height, and well requirements described below. What is an egress window and why Wisconsin requires one and can a basement room be a bedroom without one? cover this trigger rule in more depth.
What Wisconsin's Egress Code Requires
The Wisconsin UDC sets the opening size at a nominal 20 inches by 24 inches, irrespective of height or width (SPS 321.03(6)(b)1.). The lowest point of the clear opening can be no more than 60 inches above the floor (SPS 321.03(6)(d)1.); if that low point sits more than 46 inches above the floor, a permanent platform is required — at least 20 inches wide by 9 inches deep, with a top surface no more than 24 inches above the floor, rated to hold 200 pounds (SPS 321.03(6)(d)2.–4.).
These numbers are worth double-checking against what shows up on a lot of national egress-window content, because Wisconsin's own rules genuinely differ from the International Residential Code (IRC) figures that get repeated everywhere. Wisconsin UDC vs. IRC egress window rules walks through exactly where the two diverge, and the full dimension breakdown — opening size, sill height, platform, and window well — is laid out in one place in egress window size, sill height & well dimension requirements.
Window Well (Areaway) Requirements
Below grade, an egress window needs a window well — the code calls it an areaway — sized at least as wide as the window and projecting at least 36 inches out from the wall (SPS 321.03(6)(e)1.). If the bottom of that well sits more than 46 inches below grade, a permanent ladder or steps are required (SPS 321.03(6)(e)4.), with rungs at least 12 inches wide, projecting at least 3 inches from the wall, rated for 200 pounds, spaced no more than 12 inches apart, and extending to within 12 inches of grade (SPS 321.03(6)(e)5.). The well also has to drain so water doesn't end up inside the house (SPS 321.03(6)(e)6.). Where an egress window sits under a deck or porch, the code adds a clear path to open space at least 36 inches high and 36 inches wide, running no more than 15 feet (SPS 321.03(6)(f)). Window well installation covers how these areaway rules translate into an actual dug and installed well.
A window well cover is a common add-on once a well is in — but whatever cover goes on, it must never interfere with using the window as an emergency exit. A well that's code-compliant on its own can stop functioning as a second exit if the cover on top of it gets in the way. Window well covers goes into what to look for.
Permits in Madison and Dane County
Permits for basement alterations aren't triggered by a single statewide rule — Wisconsin's administrative code makes permits for alterations and repairs a local-ordinance matter, decided by each municipality (SPS 320.09(2)(b)1.). The City of Madison's own Development Services Center specifically lists basement alterations and conversions as requiring a permit. Every other municipality in Dane County sets its own process, so it's worth confirming with the local building department before work starts. Egress window permits in Madison and Dane County covers the Madison-specific rule alongside the general framing for the rest of the county.
Egress Window vs. a Regular Basement Window
Not every basement window is an egress window, even if it looks similar from the yard. The difference comes down to whether the opening, sill height, and well meet the dimension rules above — a window installed purely for light or ventilation usually doesn't. Egress window vs. regular basement window breaks down the practical differences in size, frame, and well design.
Enlarging an Existing Opening vs. a New One
Some basements already have a window opening in roughly the right spot, just undersized for egress. In that case, the existing foundation opening can sometimes be enlarged to meet the code dimensions rather than cutting an entirely new opening elsewhere in the wall. Basement window enlargement covers how that decision gets made and what changes when an opening is being cut larger in an existing foundation wall.
Egress Window Types
Egress-rated windows come in a handful of common styles — casement, slider, and hopper among them — and not every style makes it equally easy to hit the clear-opening dimensions the code requires, since some styles lose usable opening area to the sash and hardware in ways others don't. Egress window types compared lays out how the common styles stack up for this specific use.
What Installation Involves
A compliant installation touches the foundation, the window itself, and the well outside it, which is why this isn't a project most homeowners take on themselves. Cutting a new or enlarged opening into a foundation wall affects the structure around it, excavating for a window well means digging next to that foundation, and getting the sill height, platform, and drainage right all at once takes more than a tape measure and a level. What egress window installation involves walks through the general stages of a project — planning, permitting, the structural and excavation work, and the finish work — as background for what to expect, not as a do-it-yourself guide.
Related Services
Beyond the egress window itself, a handful of closely related jobs come up around the same project or later in a window well's life:
- Window well installation — sizing and installing the areaway itself
- Window well replacement — swapping out a failing or undersized well
- Window well covers — adding a cover without blocking emergency egress
- Basement window replacement — non-egress window replacement
- Window well drainage — keeping water out of a well and away from the foundation
- Window well liners & repair — repairing or lining an existing well rather than replacing it
Best Time of Year
Excavation-heavy projects like this one are affected by ground conditions more than by anything else, and frozen or waterlogged soil around the foundation makes digging slower and harder to do well in Dane County. Best season to install an egress window in Dane County covers the general seasonal factors worth knowing before scheduling this kind of work.
What Drives the Cost
Egress window installation cost depends on the foundation type and depth, how much cutting and excavation the project needs, the window and well type chosen, and any drainage or interior finishing tied to the project. Egress window cost breaks down those cost drivers without assuming a single number applies to every basement.
Service Area
This page covers egress window installation across Dane County, including Madison, Middleton, Fitchburg, Sun Prairie, Verona, Waunakee, McFarland, Monona, DeForest, Stoughton, and the surrounding communities. The full list of towns is on the service areas page.
Request a Quote
The next step for a specific basement is a quote request describing the room, the existing window (if any), and what the project is meant to accomplish — finishing a bedroom, adding light to an existing space, or something else. Questions can also go to (908) 493-5028.