Cutting and enlarging foundation openings
Most egress projects start with a bigger hole in the foundation. Here's how it's cut and what keeps the wall sound.
Few basement windows built before egress rules came along are big enough to escape through, so most projects mean either making an existing opening taller and wider or cutting a new one into a solid wall. This is the structural part of the job, and it's where experience matters most.
Poured concrete walls
Poured walls are cut with a large diamond saw, usually from both sides, and the piece is broken out and hauled away. Wet cutting controls the dust. A clean saw cut leaves smooth edges for the new window buck. Depending on the width of the opening and what's above it, the contractor may add a steel or concrete lintel, or rely on reinforcing over the opening.
Concrete block walls
Block foundations are cut the same way, but the cut leaves open block cores at the sides and bottom. Those are filled with concrete or mortar, and a header is set over the opening to carry the courses above. Older block walls that already lean or crack should be looked at before any cutting.
Things the contractor should check first
- What the wall is carrying above the new opening: a floor joist end, a beam pocket, or a load-bearing wall
- Plumbing, gas, electrical, dryer vents or a sump discharge in the way
- The condition of the wall, including cracks or bowing from clay soil pressure
- Whether the opening needs an engineered header
Why the Red River Valley clay matters
The North Dakota Geological Survey notes that much of Fargo and West Fargo sits on soft, expansive lake clays left by glacial Lake Agassiz, and some homes in the area have had foundation movement. A wall that has shifted shouldn't be weakened by a new opening without a plan. A good contractor will tell you if a structural engineer should look first.
Permits
Cutting into a foundation is structural work. In Fargo, Moorhead and West Fargo, expect the city to want a permit before the saw comes out. Moorhead's Building Codes office says no work may start before the permit is issued, and in West Fargo the city's Building & Inspections department issues permits and conducts inspections.
The installer prices the job after seeing the wall, the yard and the room. We don't quote prices, and any number given over the phone before someone has looked at your foundation is only a rough starting point.
Where we connect you with help
Common questions
Can I just make my existing basement window bigger?
Usually, yes. Most egress projects enlarge an existing opening by cutting it down toward the floor and sometimes wider. The contractor checks what's above it first.
Does cutting the foundation weaken my house?
A properly sized opening with the right header doesn't compromise a sound wall. A wall that's already cracked or bowing should be evaluated before cutting.
Related services
- Basement egress window installation
- Window wells and ladders
- Window well covers
- Basement bedroom code compliance
More background: Fargo egress window guide.
Finishing the basement or adding a bedroom down there?
Call now and a local egress window installer will help you plan the opening, the well and the permit.