# Commercial Knob and Tube Replacement

> Commercial knob and tube replacement in Minneapolis and St. Paul: mixed-use and small commercial buildings rewired around residents. Request a site visit.

URL: https://northloomminneapolisknobandtube.com/commercial-knob-and-tube-replacement/

Own an older storefront or mixed-use block with original wiring? We trace it occupancy by occupancy and replace it in phases, so your businesses stay open and your upstairs residents stay home.

A storefront below, apartments above, and often a century of wiring changes in between.

Your building has a shop downstairs and apartments upstairs, the wiring dates from the same era as the houses around it, and you can’t close the business or move people out to fix it. That’s the job this page is about.

At [Northloom Minneapolis Knob and Tube](https://northloomminneapolisknobandtube.com/), we replace knob and tube in older commercial and mixed-use buildings in Minneapolis and St. Paul: storefronts with apartments above, small office buildings and corner commercial blocks. They often carry the same original wiring as a house, with more people depending on it.

We work the way we do in a house: trace every circuit, replace whole circuits with grounded cable, and disconnect the originals at their source. What changes is the schedule, the number of occupants and the permit.

## What do you look at when you first walk the building?

We trace your building by occupancy, because that’s how it will be rewired and how your occupants and insurers will want it explained.

- **Each occupancy**: The storefront, each upstairs unit and each office suite, with its panel, meter and circuits.
- **Common areas**: Stairs, halls, basements and exterior lighting, and which panel feeds each.
- **Crossovers**: Circuits fed from one occupancy’s panel that serve another.
- **Loads**: Commercial equipment, refrigeration, signage and anything else that draws real power.
- **Your scope**: A written, phased plan with the order of work and the outage windows for each occupant.

## What usually turns up in a building with apartments upstairs?

Mixed-use buildings put commercial and residential space under one roof, and the wiring usually shows every change of occupant over a century.

| What tracing often finds | Why it matters |
| --- | --- |
| Upstairs apartments on original knob and tube, storefront rewired | The homes carry the oldest wiring and the most people |
| A shop circuit feeding an upstairs hall | One occupant’s breaker darkens another’s space |
| Common stair lighting on an apartment’s panel | One household pays for the building’s lights, and a trip leaves the stair dark |
| Original wiring above a dropped ceiling | Hidden runs over a newer storefront ceiling, sometimes buried in insulation |

We put each occupancy on its own panel and meter, with the common areas on a house panel. Upstairs units get the same protection any home does: arc-fault on bedrooms, living areas and halls, ground-fault in kitchens and baths. The [duplex rewiring](https://northloomminneapolisknobandtube.com/duplex-knob-and-tube-replacement/) page covers the residential side in more detail.

## How do you schedule around my businesses and residents?

We build the schedule around the people using your building.

- **Storefronts**: Work above ceilings and in the basement during business hours; changeovers before opening or after closing.
- **Upstairs units**: One unit at a time, with dates and outage windows passed to residents through you.
- **Common areas**: Done when they’re least used, with temporary lighting where people need safe access.
- **Refrigeration and critical loads**: Kept on a working circuit, or switched over in a short planned window.

## Will the permit need drawings?

Sometimes. Commercial electrical work runs through the same offices as residential: the Minnesota Department of Labor and Industry in Minneapolis and many suburbs, the City of Saint Paul’s Department of Safety and Inspections in St. Paul, or the city’s own inspector where a suburb runs one. The commercial permit goes in at or before the start of work, and larger or more complex projects can call for drawings. We confirm that with the inspecting office when we write your scope, and getting the permit in place is part of the job. The [permit guide](https://northloomminneapolisknobandtube.com/guide/minneapolis-electrical-permits-for-rewiring/) explains the inspection sequence.

## How do you keep the building earning while you rewire it?

Most owners need rent and sales to keep coming in. A phased plan is how we do that.

| Phase | What happens |
| --- | --- |
| Trace and plan | We trace the whole building and agree a phase order with you |
| Panels and service | New panels set and service capacity added, often first, so new circuits have somewhere to land |
| Occupancy by occupancy | Each space rewired and switched over in its own window |
| Common areas and cleanup | Shared circuits moved to the house panel; original runs disconnected and exposed runs removed |
| Record | A written record for each occupancy and for the building |

## Can the old circuits handle what my businesses run now?

Usually not. Original wiring was sized for lights and a few small motors. Commercial spaces now run refrigeration, cooking equipment, computers, signage and air conditioning, often on circuits never meant for them. We run a load calculation for each occupancy, and that sets the panel sizes and your building’s service. The [guide to modern appliance loads](https://northloomminneapolisknobandtube.com/guide/knob-and-tube-and-modern-appliance-loads/) explains why original circuits struggle.

## Is there old wiring hiding above my dropped ceiling?

Often, yes. A storefront remodeled several times may have a suspended ceiling grid a few feet below the original plaster or pressed-tin ceiling, with knob and tube still running across the space between. Original runs also hide behind newer drywall or display walls.

- **Above the grid**: Ceiling tiles lift out, so we can usually see and trace original runs above a dropped ceiling.
- **Insulation**: Insulation laid on top of ceiling tiles can bury original runs, the condition the code bars.
- **Old ceilings**: We leave pressed-tin or plaster ceilings above the grid in place and run new cable in the space between.
- **Behind newer walls**: We follow runs from where they enter and leave, and open finished storefront walls only when we have to.

## Is it legal to keep knob and tube in a commercial building?

Existing knob and tube isn’t unlawful in Minnesota just because it’s old, but the code allows it only to extend existing installations and bars it in insulated spaces. Your commercial property insurer will often ask more detailed questions than a homeowner carrier, and your residents’ own insurers may ask too. A building-wide record of what we replaced, disconnected and had inspected is what answers them. The [guide to whether knob and tube is legal in Minnesota](https://northloomminneapolisknobandtube.com/guide/is-knob-and-tube-legal-in-minnesota/) covers the code.

## What sets the price on a commercial job?

We price commercial rewiring from the circuit list for each occupancy. On top of that come the number of panels and meters, any service upgrade, phasing around your businesses and residents, after-hours changeovers and any drawings the permit needs. You get a written estimate built from those parts before anything is scheduled. The [cost guide](https://northloomminneapolisknobandtube.com/guide/knob-and-tube-replacement-cost-minneapolis/) shows how we build residential prices, and the same parts apply here, multiplied by the occupancies.

## What record do I get at the end?

We organize it by occupancy: each storefront, office and apartment with its circuits, panel and meter, plus the house panel and the common areas it feeds. It lists each original circuit we disconnected and how we tested it, and the permit and inspection dates. You’ll use it with your commercial property insurer, your residents’ insurers sometimes ask for the part covering their space, and a future buyer’s due diligence will ask the same questions.

> What to have ready
>
> A list of the occupancies and who uses each, any insurer correspondence, and the hours each business needs power. Questions:
>
> (612) 509-6597
>
> .

## What's included

- Tracing circuits by occupancy: storefront, upstairs units and common areas
- Finding circuits that cross between occupancies
- A phased scope that keeps your businesses open and your residents in place
- New grounded circuits with protection where the code lists it
- Panel and service planning for the whole building
- The permit, with drawings where the inspecting office asks for them
- A written record for you, your insurers and your residents

## House or commercial building: what changes

| Question | Single-family house | Mixed-use or small commercial building |
| --- | --- | --- |
| Occupancies | One household | A business plus residential units, or several businesses |
| Scheduling | Around one family | Around business hours, customers and residents |
| Panels and meters | Usually one | One per occupancy plus a house panel |
| Permit | Residential | Commercial, sometimes with drawings |
| Insurance | Homeowner policy | Commercial property policy, plus residents' own |

## Guides behind this service

- [**Who Issues the Electrical Permit for a Minneapolis Rewire?** You call the city for most permits, but not this one. Here's who inspects your rewire in Minneapolis, St. Paul and the suburbs, what it costs you and when the inspector comes.](https://northloomminneapolisknobandtube.com/guide/minneapolis-electrical-permits-for-rewiring/)
- [**Is Knob and Tube Wiring Legal in Minnesota?** Your knob and tube isn't outlawed. The code limits what you can do with it, and your insurer, a buyer or an insulation contractor will often ask for more than the code does.](https://northloomminneapolisknobandtube.com/guide/is-knob-and-tube-legal-in-minnesota/)
- [**How Much Load Can Knob and Tube Wiring Handle?** Less than your house probably asks of it. Here's the arithmetic, and why the tempting fix makes it worse.](https://northloomminneapolisknobandtube.com/guide/knob-and-tube-and-modern-appliance-loads/)
- [**How Much Does Knob and Tube Replacement Cost in Minneapolis?** Our typical ranges for whole-house and partial jobs, what goes into a Minneapolis price, the permit fees you'll pay, and why two quotes for the same house can be thousands apart.](https://northloomminneapolisknobandtube.com/guide/knob-and-tube-replacement-cost-minneapolis/)
- [**How Does Knob and Tube Replacement Work?** You've decided the old wiring has to go, and you want to know what happens next. Here's each step, from the first circuit we trace to the final inspection, and what it means for you.](https://northloomminneapolisknobandtube.com/guide/how-knob-and-tube-replacement-works/)

## What happens after I call?

### You call us

Tell us what was found and where: an inspection report, an insurer's letter, a stalled insulation job. Photos and the report help.

### We evaluate

We trace your circuits, check the panel and look at the attic and basement runs. You get a written scope that separates electrical work from patching.

### We do the work

We get the permit in place, route cable in stages, and have the rough-in inspected before your walls are closed.

### We close it out

Final inspection, a labeled panel, and the circuit record you will need for an insurer or a sale.

## What this work looks like

Row of six electric meters on a painted brick basement wall with new cables along the ceiling

Group of new electrical panels on a plywood board with a conduit riser up a brick wall

## Commercial and Mixed-Use Buildings: questions

### Can a business stay open while the building is rewired?

Usually, yes. We phase the work so your storefront keeps power during business hours, with changeovers before opening, after closing or on a day the business picks. Upstairs units go one at a time. Your scope gives each occupant their days and outage windows ahead of time.

### Does commercial knob and tube replacement need drawings?

That depends on the size and type of your building and on the inspecting office. Smaller jobs often go through on a permit alone, while larger or more complex ones can call for drawings. We confirm it with the office for your address when we write the scope, so the permit isn't held up.

### Who inspects commercial electrical work in Minneapolis?

The Minnesota Department of Labor and Industry inspects electrical work in Minneapolis, commercial as well as residential. In St. Paul, the city's Department of Safety and Inspections does. Other cities either use the state or run their own electrical inspection, and we confirm which for your address.

### Is knob and tube in a commercial building treated differently from a house?

The code rules on concealed knob and tube are the same: extensions only, and never buried in insulation. What changes around them is the number of occupants, commercial loads, separate panels and meters, and an insurer that underwrites your building as commercial property. That insurer may ask more detailed questions than a homeowner carrier would.

### What about the apartments above a storefront?

We treat them like any home: each unit gets its own circuits on its own panel, with arc-fault and ground-fault protection where the code lists it. We find any circuits that cross between the storefront and the apartments, or between units, and separate them.

## Related services

- [**Duplex and Triplex Rewiring** Own a duplex or triplex with original wiring and people living in it? We trace each unit, untangle the circuits that cross between them, and rewire one household at a time.](https://northloomminneapolisknobandtube.com/duplex-knob-and-tube-replacement/)
- [**Whole-House Rewiring** Most rooms still on the original wiring? We replace every branch circuit with new grounded cable, the knob and tube and everything spliced into it since, under one permit and its inspections.](https://northloomminneapolisknobandtube.com/whole-house-rewiring/)
- [**Panel Upgrades** Still on a fuse box, or out of spaces in your panel? We replace it with a breaker panel sized for your house, and we check the circuits behind it first, so a new panel doesn't end up sitting on old wiring by accident.](https://northloomminneapolisknobandtube.com/electrical-panel-upgrade/)