03:36AM | 02/22/00
Member Since: 02/21/00
1 lifetime posts
I just bought a old 2-story colonial (1924), and about 35% of the wiring is knob & tube. After reading a little about it, and examining it in the basement, I want to get rid of it. Most of the remaining knob & tube is on one circuit breaker that feeds a line that runs the length of the house.

It looks like it feeds most of the outlets in the LR, DR, and probibly the ceiling lights, and the upstairs BRs.

I figure I can fish new wire up through the basement for the outlets on the first floor, and I can feed down through the walls from the walk-up attic for the second floor. My PROBLEM is the three ceiling fixtures (on wall switches) on the first floor.

How does one replace the wiring in these? I was thinking about tying a string to the old wire when I pull it out, and using that string to fish new wires. HOWEVER, I do not know if they used the "tubes and knobs" in the walls and in the ceilings...the ceramic tubes would make this very difficult. Will I have clearance to pull the new wire through?

Anyone? Thanks.

Joe Tedesco

04:22AM | 09/29/02
Member Since: 07/27/02
140 lifetime posts

[This message has been edited by Joe Tedesco (edited April 09, 2003).]


04:00AM | 09/30/02
Member Since: 09/27/02
9 lifetime posts
The ceiling will have to be cut into to refeed the fixtures. The problem with knob and tube is you can have one wire coming in from one direction and the neutral(grounded conductor) coming in from the other.
As far as replacing all of the K & T it may be extemely difficult to do.
Some insurance companies will not issue a policy if the house is wired wiht K & T, one problem was and now is the blown in insulation especailly on the exterior walls, where the wire is run to go to the second floor.
Knob and tub by itself was not a bad system and worked well, it just wasnt expected to supply the numerous loads we have today.
that said, you might want to check it first to see if it really needs to be replaced especially in the ceilings, those few lights may well be ok with the current system, as long as you reduce the other loads laundry refrigerator &c.
But add new small appliance circuits for the kitchen, Refrigerator circuit, laundry circuit, this will help alleviate most of the heavy loading on the old system. These suggestions are intended if you have the space in the service panel to locate the new circuits.

Electrical Inspector

02:26PM | 09/30/02
Member Since: 09/27/02
73 lifetime posts
Right on Mark.

you could have some switched receptacles in the LD & DR.....

or you could ( as Mark alludes) take all possible load off the leg of K&T that does the cieling fixtures, disconnect the fixtures, megger the remaioming cuircuit out to establish some integtrity.

reduce the fuse/breaker size to less than normal ( basically derate for age & wear)

rebox the fixtures with 'old work octogons', prefereably plastic.

add 90 deg pigtails to the K&T

find new lighting fixtures of a plastic variety, or basically something that does not require grounding.

there are also some specialty breakers that would enhance the safety of the older circuit.

this may all sound extensive, but whatever you choose please get back to us, there are members that can address specifics for you.

good luck.



Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.


type the code from the image


Post_new_button or Login_button

For an eclectic table setting or outdoor lighting, try a riff on this project from The SITS Girls blog—converting mason ja... It turns out that many bath and kitchen cleansers contain chemicals that are dangerous to the skin and eyes, and often pro... So often we paint tiny nooks white to make them appear larger, but opting for a dark, dramatic wall color like this one—Be... Chocolate-colored walls and large window frames allow the exposed wood beams to take center stage in this small screened p... If you're not crazy about the idea of commingling plants and pool, this modern variation may be more to your liking. The s... Yes, a freestanding garage can become its own tiny house. Artist Michelle de la Vega has all the comforts of a modern resi... There’s nothing like a new set of cabinet hardware to refresh a room. The possibilities are endless: Go modern, rustic, or... Pursue what's known as the stack effect. To achieve it, open the windows on both the upper and lower floors, and as warm a... Like no other floor type, a checkerboard design works wonders to underscore the retro kitchen theme. Vinyl flooring, ceram... Twine lanterns add pops of crafty—but sophisticated—flair to any outdoor setting. Wrap glue-soaked twine around a balloon ... When securely fastened to a tree or the ceiling of a porch, a pallet and some cushioning make the ideal place to lounge. V... Incorporate nature into your lighting scheme by securing a dead tree in a concrete mold and draping your pendant lamp from... For the cost of a can of exterior paint , you can totally transform your porch. Paint the floor a hue that complements yo... In this urban apartment, a standard-issue patio became a serene and green perch by replacing the typical concrete with gro... If you put the washing machine in the mudroom, you can stop the kids from walking through the house in dirty, grass-staine...
Newsletter_icon Google_plus Facebook Twitter Pinterest Youtube Rss_icon