HOW K&T WORKS
K&T wiring consists of insulated copper conductors passing through wood framing in drill holes with porcelain insulating tubes placed in the hole. They are supported along the runs with nail down porcelain knobs. Where wires enter a wiring device such as a switch box, plug box or fixture it is protected by a cloth and rubber sleeve called a loom.
ADVANTAGES OF K&T
K&T wiring has a higher current carrying capacity than new wiring of the same gauge. Because they are run separately unlike new Romex that is all enclosed in the same sheathing, K&T can dissipate heat easier. When left alone and not modified or added to by an unqualified person, K&T wiring is in amazingly good shape and still very functional. When this kind of reckless damage has occurred it doesn’t mean you have to rewire the whole house. A qualified electrician armed with K&T experience can make necessary repairs.
K&T REPAIRS AND TLC.
Making qualified repairs and restoring it to its original safe condition is top priority. Once that is done it is crucial to be sure it is protected by the correct size circuit breakers and not still on glass fuses. Sometimes it requires a panel upgrade to complete the safety of the existing K&T. Once a panel with circuit breakers is assured then it is time to bring in dedicated circuits to the larger load equipment in the house such as a refrigerator, a washing machine, microwave, disposal/dishwasher. Because K&T is a 2 wire system that means there is no ground at the plugs. Not to worry, most small appliances from cell chargers to table lamps and even most toasters only have a 2 prong cord cap. Where a ground is needed, K&T can be grounded down the wall to a cold water pipe under the house or a ground rod outside the home in an inconspicuous place. And now with the advent of LED light bulbs and fixtures the load on circuits is greatly reduced. Check with your neighborhood fire department to see if there is a lot of fires due to K&T. I doubt there is.
It is far more expensive and rarely necessary to rewire the house as opposed to the “TLC” method we mentioned above. In fact, studies have shown that K&T wiring is no more likely to start a fire than modern, grounded wiring. With over 30 years of K&T experience and having lived in K&T homes for a very long time, we are the premier experts in K&T wiring. If you are considering removing and replacing knob and tube wiring in your home, it is important to weigh the risks and benefits carefully. There is no one-size-fits-all answer, and the best decision for you will depend on your individual circumstances and consultation with your expert K&T electricians at Metcalf Electric.