Pre-1950s houses, North Portland
Knob and Tube Abatement
We disconnect and remove the old knob and tube wiring and install new wiring and junction boxes, so an insulation crew can finally cover the attic and an insurer has nothing left to flag.
Chapter 01
What knob and tube is still doing in a St. Johns attic
Most of the houses around our shop on N Lombard Street predate 1950, and a lot of them were wired for a house with one lamp and a radio, not a kitchen full of appliances and a garage full of chargers. The insulation on knob and tube conductors ages the same way any insulation does: it dries, it cracks, and it stops doing the one job it has. That is a higher fire risk than a modern circuit carries, and it is why an insurance company looking at an older Portland home so often asks about it before anything else.
There is no ground conductor in a knob and tube circuit, which is the other half of the problem. Touch the wrong thing at the wrong time and there is nothing routing that fault away from a person. It was never built for the load a modern house puts on it, and it makes it hard for an insulation contractor to do their own job right, because code will not let them bury live knob and tube under blown-in insulation.
A wall of vintage switchgear and disconnect panels labelled by circuit inside the Bridgetown Electric shop on N Lombard Street
How we clear it out and wire the attic modern
We disconnect and remove the existing knob and tube wiring and install new wiring and junction boxes in its place. If there is already insulation sitting over the old wiring, that has to come out first before we can get to it safely, so walk the attic before you call if you can and tell us what you find.
Our base price is $3,495 per attic or crawl space area for that removal and re-wire. Wiring on to the devices, switches and lighting fixtures themselves is priced additionally once we've seen what's actually up there and how many drops it feeds. Conditions apply. Pricing subject to change.
Bridgetown Electric has been doing this kind of work in North Portland's older housing stock since 1994, two generations now, and we're licensed, bonded and insured under CCB #103824. Estimates are typically available within one to two weeks. Call (503) 621-7122 to get on the schedule.
Chapter 03
What changes once the old wiring is out
Once the knob and tube is disconnected and removed, the insulation crew you hire can finally do a proper job covering that attic, and the insurance question most owners called us about in the first place usually closes itself. The new wiring and junction boxes we install are built for the load a modern house actually runs, not the one it was wired for in 1948.
If you're not sure whether a room or an attic still has knob and tube in it, the giveaway is usually visible from the attic floor: two separate cloth-insulated conductors run apart on porcelain knobs and tubes, instead of one sheathed cable. If that's what you're looking at, it's worth a call before an insulation job or a sale closes around it.
Bridgetown Electric — Licensed, bonded and insured. CCB #103824, electrical contractor 26-887C. Call (503) 621-7122.