Do you need a permit?

Almost always. Cutting an opening in a foundation wall is structural work, and finishing a basement room to sleep in changes how that room is classified. Both of those are the building department's business. Here is what the paperwork costs, who normally files it, and the single number worth phoning them for.

What it costs

There is no national permit fee, and anyone quoting one is guessing.

Permit fees are set by the city or county, published by the city or county, and they differ between neighbouring towns. So instead of an average, here is one real published schedule, read in full and linked, worked through on a job the size we actually recorded.

East Lansing, MI, as published on 2026-08-31
Application, zoning review and base fee Non-refundable. You pay it whether or not the permit is granted.	$60
Each inspection Charged per inspection, and a job can need more than one.	$70
Work valued $1 to $2,000 Flat fee for the lowest valuation band.	$70
Work valued $2,001 to $25,000 $70 for the first $2,000, plus $14 for each additional $1,000 or fraction of one.	$70 +

Source: East Lansing building division fees. One town in Michigan, not a national figure. No plan review charge below $50,000 of building valuation, which covers any egress window job.

Worked through

A $6,000 job, the median of the 24 installed prices we recorded.

Base fee	$60
Permit fee on $6,000 of work	$126
2 inspections at $70	$140
Paperwork total	$326

The number of inspections is our assumption, not the schedule's: the city publishes the price of an inspection, not how many your job needs. Ask them. Every other line here is arithmetic on their published rates, and on that job the paperwork is roughly 5% of what the work itself costs.

Who files it

2 installers we recorded state the permit in the price.

Whether the permit is yours to pull or theirs is a question to settle before signing, not after. These prices came off their own public pages, and the permit is named in the same breath as the number.

$3,000

Egress Systems, Inc. · PA

Egress Systems, Inc., read 2026-08-30

$3,199

All Good Egress · MN

Standard Andersen Clad Egress Window. All Good Egress, read 2026-08-30

Ask any contractor the same three things: who files, who pays the fee, and whether a failed inspection is re-inspected at their cost or yours.

Buried gas line warning tape uncovered while excavating beside a foundation — Photo: The Great Egress Co.

Before the permit, one free phone call

Dial 811 and have the utilities located.

A window well is a hole dug hard against the house, which is exactly where the gas, water and electric services run. The tape in this photo is the warning you get if you are lucky. In the United States, 811 is the free national number that sends a locator out to mark what is buried before you dig. It is not the permit, it does not replace the permit, and no permit protects you from a service you did not know was there.

The one number to ask for

Ask which net clear opening they apply.

The model code sets the net clear opening at 5.7 sq ft (R310.2.1, 2021 edition). Local jurisdictions amend it, so the figure your inspector applies is the figure that decides which windows can pass. Get it on the phone before you buy anything, because a window bought against the wrong number is a window you own and cannot use.

See the windows with their published net clear opening

Every size we list carries the opening its maker publishes, so you can hold it against the number your department gives you. Glass block, and why it never clears it.