Basement windows
Basement Egress Windows Cut and Installed in Wentzville
We install egress windows in Wentzville basements: cutting a larger opening in the foundation wall, setting a window sized to the city's escape-opening rules and building the well outside, so a finished basement bedroom has a legal second way out. We also replace basement windows in their existing openings.
Wentzville's Size Rules for a Basement Escape Window
The City of Wentzville's guide to finishing a basement sets three measurements for the emergency escape window in a basement sleeping room:
From the city's Finished Basement Guide
"Clear" means the open space you could climb through with the window fully open, not the size of the frame. That's where small basement windows fall short: once the frame and a sash are subtracted, a window that looked big enough isn't. A casement swings fully out of the way, so it often meets the numbers in a smaller opening than a slider would.
We size the window from these numbers, set the sill at the right height inside, and confirm the details against the city's current guide when the permit goes in.
Cutting the Foundation Opening for Egress Windows
Before any cutting, we mark what runs inside and along that wall (gas, water, electrical, the sump line) and pick a spot that avoids it and suits the room you're building. Outside, the soil is dug out down past the new sill height.
The opening is cut with a water-fed concrete saw, which keeps dust down, and the inside of the basement is sealed off with plastic while we work. In a poured wall the cut edges are clean and solid. In a block wall, the cut cores are filled and a header goes across the top. The new window is then set, anchored and sealed to the wall on all four sides.
The Well, the Drain and the Cover
The window well has to be wide and deep enough for the window to open all the way and for someone to climb out. A deep well gets steps built into its side or a ladder fixed to it. The bottom is gravel over a drain, so water heads away from the wall instead of collecting against the glass.
Last comes the cover: a clear one lets daylight through, keeps leaves and snow out, and stops anyone from stepping into the hole by accident, while still lifting off from inside the well when it has to.
Swapping a Basement Window Without Enlarging It
Not every basement window needs to become an egress window. In an unfinished basement, a storage room or a utility area, the job is usually swapping an old single-pane or steel window for a new vinyl one in the same opening: a hopper that tilts in from the top, or a slider. No saw, no digging, and the basement stays drier and warmer.
If the old window sits low in a well that fills with leaves or water, we'll point that out while we're measuring, since a new window in a wet well won't stay new for long.
Egress Window Questions
Does an egress window need a permit in Wentzville?
Cutting a larger opening in a foundation wall modifies the structure, so it goes through the City of Wentzville's Building Division. Applications are filed through the city's SmartGov portal, and we handle the paperwork and the inspection timing as part of the job. If the window serves a basement you're finishing, it's usually reviewed along with that project.
Will an egress window let water into the basement?
Not when the well drains. We set the well on a bed of gravel tied into the footing drain where the house has one, or into a drain at the bottom of the well, and seal the window flange to the wall. A cover over the well keeps out most rain and leaves; the drainage handles the rest.
How much of the yard gets dug up?
A hole a little bigger than the well, dug against the house. The soil is piled on tarps, used to backfill around the well and the rest hauled off. Expect to reseed or replace the mulch in that patch once it settles.
Can the window go in before the basement is finished?
Yes, and it's often the easiest time. With bare walls inside there's no drywall or trim to protect, and the framing for the finished room can be built around the new opening.
Planning a basement bedroom?
Send us the room and wall you have in mind. We'll look at the wall, the yard outside it and the window that fits the city's numbers.