What 'Up to Code' Means for a 1905 House

“Up to code” sounds like one standard. In a house built in 1905 and remodeled every few decades since, it’s really three questions: what rules the old work answers to, what rules your new work answers to, and who gets to check.

Existing work stays

Wisconsin’s electrical code is direct about this. Existing electrical installations “shall conform to the electrical code that applied when the installations were installed,” and so do repairs to them ¹. Your 1950s cloth-covered cable or a run of knob-and-tube isn’t illegal just because today’s code wouldn’t allow it in a new house.

There are two limits. First, anything “known to be defective so as to endanger life or property” must be promptly repaired, permanently disconnected, or isolated until it can be fixed ¹. Second, when an existing installation is or creates a hazard, the authority having jurisdiction, in practice the electrical inspector, may require it to be brought up to the current code ¹. Grandfathering protects old work that’s sound, not work that’s dangerous.

New work meets today’s code

The same chapter applies “to all new installations, reconstructions, alterations and extensions,” and additions and alterations must comply with the code in force at the time of permit application, or at the start of the project if no permit is required ¹. That code is the 2023 National Electrical Code, adopted with Wisconsin’s own changes ².

So the moment you touch a circuit, the part you touch is judged by today’s rules. Replace a switch and the replacement must follow current requirements for switches. Extend a circuit and the extension must follow current wiring rules. Add a bedroom circuit and it gets today’s protection. The next lessons go through the cases you’ll meet most: switch loops, AFCI and GFCI, alarms, and the service.

The house itself

Wisconsin’s Uniform Dwelling Code (SPS 320 to 325) covers one- and two-family dwellings built on or after June 1, 1980, and additions and alterations to those dwellings ³. A 1905 house is not a UDC house. That doesn’t mean anything goes: cities regulate building, plumbing, and electrical work by ordinance and permit.

In Stoughton, that’s Chapter 10 of the municipal code. Permit fees are paid to the Planning and Development Department before a permit issues; permits for one- and two-family remodeling and additions are good for 24 months; and the building inspector can suspend or revoke a building, plumbing, or electrical permit if the work doesn’t comply ⁴. Call the department before a project and ask what needs a permit; the answer is cheaper than a correction order.

Who may do the work

State law generally requires licensed electricians, but it exempts a residential owner who installs, repairs, or maintains wiring in a home the owner owns and occupies, unless a local ordinance requires a license ⁵. Doing your own work doesn’t excuse you from the code or from permits.

The one place you can’t go it alone is the service. The utility won’t energize a new or rebuilt service until it has an authorized electrical inspector’s certificate of approval ⁶.

Try it

Make a list of every change you’ve seen evidence of in your house: a newer panel, Romex in the basement, a remodeled kitchen, three-prong outlets on old wiring. For each one, ask: is it old work that’s sound, old work that’s a hazard, or new work that should meet today’s code? That list is your upgrade plan.