Tell me about upgrading wiring in a house

In My Humble Opinion
1

We have a fairly small house; the main floor is two bedrooms, a bathroom, a living room and kitchen. The downstairs contains a 1-car garage, a large bedroom and bathroom, and an open area used as an office, and storage under the stairs.

The kitchen and bathroom upstairs were remodeled, and the wiring of course updated. A new panel was put in upstairs at the time, but it only connected to those two rooms at the time.

The downstairs was completely remodeled in a separate project, except for the garage, and the wiring updated there too of course. I’m not positive (I know I should know this but I’m not positive) but I think the downstairs is also connected to the new panel upstairs. The old panel in the garage was too small to accommodate the remodeling needs, as I understood it at the time.

So what remains are the 2 bedrooms and living room upstairs, and the garage downstairs. The house was built in 1949 so I’m fairly certain those areas have knob and tube wiring. I am thinking of having the rest of the house re-wired, mostly for the safety factor. If you have had experience in this area either as a contractor or as a homeowner, can you give me an idea of how long such a project would take, how disruptive it might be, and some ballpark about what it might cost?

2

My house is probably a similar size, about 1000 sq ft, built in 1950, DC suburbs. I’ve gotten a few estimates and they usually come back with 3-5 days, $5000-8000. If you’re in the San Francisco area, I’d add maybe 20%.

3

They are going to know holes in the walls to remove and replace the wires, so there’s that mess and expense. And new paint as well afterwards.

In my area I’ve had good experiences with Home Advisor. You enter information regarding your project and contractors will call to talk to you.

I’d assume though that the really top guys who are all booked up may not be the ones calling.

4

Insurers commonly refuse to cover houses with knob and tube wiring. There might be a clause to that effect in your homeowners policy.

So that’s another reason to get rewiring to modern standards done as soon as possible.

5

Since your house was built in 1949, this sounds like it was slightly after the knob and tube era.

Are your electrical outlets in the bedrooms, living room and garage two-pronged or three-pronged?

6

?? They don’t do any of that around here. A new powerpoint costs around 50USD (although the minimum callout is more), and they just disconnect the old wires and poke the new wires through. Power outlets are always big enough to cover the hole in wall and no painting is required. Obviously, depends on your wall material: double brick would be more difficult.

knob and tube stopped much earlier here, but if I had 1949 wiring the insulation would be perished and the sockets and switches in even worse shape.

7

The garage is probably later now that I think about it, the outlets are definitely 3-pronged, and we run a washer and (gas) dryer out there. The upstairs outlets are 2-pronged. During the upstairs remodel, I think I remember seeing knobs and tubes, or at least wires that were separate instead of in a cable, in a wall that got partially exposed.

8

Without making holes, or slots, in the walls, how do they get the new wires past the studs from one bay to the next? With a one story and an unfinished basement it’s easier because you can come up through the sill plate into the correct stud bay.