Most basement windows are too small to count as an egress window. Making a code-sized escape opening means changing the foundation itself, so it helps to know what happens on installation day and why each step matters.
Here is how the work usually goes, from planning to finished trim.
1. Choose the location
The spot is picked from both sides of the wall. Outside, the well needs room to dig and should not sit under a driveway, against an air conditioner or over buried utility lines. Inside, the window should be easy to reach, not blocked by a bed, stairs or built-ins.
If the window will sit under a deck or porch, plan for at least 36 inches between the top of the window well and the bottom of the deck or porch joists. That is the clearance Michigan building departments, such as Grand Haven Township, list in their egress handouts.
2. Size the window
Egress is measured by the clear opening when the window is fully open, not by the glass. Michigan's residential code calls for at least 5.7 square feet of clear opening, at least 24 inches high and 20 inches wide, with the sill no more than 44 inches above the floor.
The window style changes how big the unit has to be. A casement window swings clear of the opening, so it can be smaller. Sliders and double-hung windows block part of the opening and need a much larger unit. Manufacturers list the clear opening for their egress models, which makes it easier to compare.
3. Get the permit
Because the foundation is being cut, this work typically needs a building permit and inspection. Your local building department confirms what applies to your home and when inspections happen.
4. Mark utilities and dig
Before any digging, underground utilities are marked through MISS DIG 811, Michigan's free call-before-you-dig service. Then the area outside the wall is excavated deep enough for the new opening, the well and a drainage base.
5. Cut and reinforce the opening
The new opening is laid out and cut into the concrete or block wall. Making an opening taller usually takes less structural work than making it wider, because a wider opening may need a stronger header above it to carry the wall's load. The opening is then reinforced so the wall stays solid around it.
6. Set and seal the window
The window is installed in the new opening, then flashed and sealed so water stays out. This step protects the finished room on the other side of the wall, so it is worth doing carefully.
7. Build the well and backfill
The window well goes in next, with a base that lets water drain. Wells deeper than 44 inches need a permanent ladder or steps so someone can climb out. The soil is backfilled and graded so water runs away from the house.
8. Finish the inside
Inside, the opening is trimmed out to match the room, whether that means drywall returns, a wood jamb or a deep sill. The finished window should open easily with no keys or tools.
Plan it with the rest of the basement
An egress window is easiest to add before a basement is finished, when walls are open and the layout is still flexible. If you are planning a bedroom, office or family room downstairs, decide on the window location early.
See how we approach egress windows, or read about planning a basement bedroom.
