Cost To Replace Knob and Tube Wiring (2022 Estimates)

If you want to replace the knob and tube wiring and looking for an idea on the cost, you are in the right place!

In this guide, you will learn:

  • The cost breakdown of changing out knob and tube wiring systems
  • Ways to save money when replacing knob and tube wiring 
  • Extra costs to consider when replacing knob and tube
  • And more!
cost to replace knob and tube wiring

Knob and tube electrical wiring was the standard style of wiring beginning in the 1880s and was used until roughly the 1950s—but some communities well into the 1960's! As long as it is in safe and functional condition, you don't have to replace this style of wiring; it is recommended.  

Due to this wiring not having a ground wire, it can be dangerous to use with the modern day electronics we have today.  Along with not having a ground, the wiring most likely will not meet code standards needed for safely running today's appliances creating a potential fire hazard. 

Keep reading to learn more about the average cost to replace knob and tube electrical systems!

How Much Is Knob And Tube Replacement Cost?

The average cost to replace knob and tube wiring ranges anywhere from $3,500 to $9,000.

The cost to replace knob and tube electrical wiring can be difficult to estimate because of all the factors that play into replacing it. The size and complexity of your house, the amount of wiring you are replacing, and the cost of labor and materials in your area all play a major role in the cost. 

You have to keep in mind that it is not just the wiring that will need to be replaced. To expose the wiring, holes will have to be cut in the walls and ceilings. These will need to be repaired or replaced as well, adding to the overall cost.

Read Also >> How To Wire And Add An Electrical Outlet? 

Average Cost To Replace Knob And Tube Electrical Wiring If It's DIY?

The average cost to do it yourself would be an average of $2.65 per square foot.

To figure out a good estimate for replacing knob and tube wiring yourself, you will need to price all the materials that will need to be purchased. This will include all the permits you will have to get before beginning your work and inspections you will have to get after.  

DIY Vs. Hiring A Pro

When deciding to do your own wiring, you may think if you do it yourself, you won't have to pay for labor.  In the end, you pay for it, just not in a monetary way.

Depending on how extensive the project is, it is worth considering how fast you want the project done, how much time you will get to work on it, and how often. If you don't have a lot of time to dedicate to the project and you want it done sooner rather than later, you may want to consider hiring it out. 

knob and tube wiring replacement cost

How To Estimate The Cost Of Replacing Knob And Tube Systems?

When estimating the average cost of replacing knob and tube wiring, you will need to find out the current prices, in your area, of the materials you will need. Here is a list of considerations when pricing out knob and tube: 

  • the cost of NM cable (14-2, 14-3, and 12-2 are the common household cables used)
  • the cost of hired labor if you are not doing it yourself
  • the number of outlets and fixtures you will need 
  • the cost of wire nuts and wire staples 
  • the cost of wall plates for the outlets 
  • the cost of a new main panel 
  • permits and inspections
  • dumpster cost if you are removing a large amount of wall and ceiling coverings
  • cost of patching or replacing the wall and ceiling coverings 

Depending on the extent of your project, you could hire an electrician to come and do the wiring; then hire someone to come and repair or replace your drywall.  

Another option to consider is hiring a general contractor to over-see the entire project and they will take care of hiring the subcontractors.

While it might end up being a little cheaper for you to individually hire each contractor, if you don't want to deal with multiple contractors, or if you are doing an extensive remodel at the same time, a general contractor may be the way to go.

Read Also >> How To Wire A Light Fixture With Red, Black, And White Wires? 

Estimated Cost of Labor For Replacing Knob And Tube?

The cost of labor for knob and tube wiring replacement will be an average of $75-$125 for the first hour and then $40-$100 for every hour after.

If they are doing a percentage of the overall job total, it could be in the range of 15% to 20%. Material prices may be marked up by an average of 7.5% to 10%.

Contractors have a couple different ways they may bid on your job. They will either estimate their time by the hour or a percentage of the total job cost.  Often times they will mark up the materials cost by a percentage as well. 

How To Save Money When Rewiring Knob And Tube Electrical Systems?

One way to save money when replacing knob and tube wiring is to do all the demolition work required to expose the wiring, you could rent a dumpster and do it yourself.   

You could also consider not replacing the wiring all at once and doing it in stages.  

When purchasing outlets, fixtures, and cover plates watch for contractor packs. Typically, bulk purchases are a little cheaper than buying just a couple.  

Price shop between big box stores and your local electrical supply company for everything you need.

If you are planning on hiring someone to replace your wiring, get quotes from multiple contractors.  You may want to consider getting 3 to 5 quotes from either electrical contractors or general contractors to take care of the entire project for you.

Read Also >> How To Wire A Single-Pole Light Switch?

Frequently Asked Questions

Is It Worth Replacing Knob and Tube Wiring?

Replacing knob and tube is worth it because it does not have a ground. Also, because of its age, the insulation can be very brittle and create a potential fire hazard. 

How Much Does It Cost To Replace Knob and Tube Electrical Systems?

The average cost for replacing knob and tube electrical wiring is between $3,500 to $9,000. Many factors can play into the cost of upgrading your wiring. 

Does Knob and Tube Wires Have To Be Replaced? 

As long as the wiring is safe and functional, it does not have to be replaced, but it is recommended to replace it. 

Can You Partially Replace Knob And Tube Electrical Systems? 

Yes, you can partially replace the wiring. Note that connecting new wiring to old knob and tube wiring can create hazards.

What Is Knob And Tube Electrical Wiring?

Knob and tube wires pose an obsolete electrical wiring system that was installed in the late 19th and early 20th centuries. According to Wikipedia, the obvious indicator of knob and tube systems are porcelain tubes or cylinders that are inserted into old floor joists.

When Were Knob And Tube Electrical Systems Used?

Knob and tube wiring was a common wiring standard from the 1880's to 1940's in the USA and other countries.

Are There Knob And Tube Removal Grants?

There aren't any current federal grant money for knob and tube removal, but some states have what are known as 'barrier mitigation grants' such as in Massachusetts. Homeowners can get up to $7,000 in grant money if the knob and tube wires interfere with new insulation. However, you only get the money after proving that you have newly insulated your home.

Read Also >> Is The White Or Black Wire Hot? (Basic Wire Identification)

Final Thoughts

Before undertaking a major remodel, take time to consider all the costs you are going to incur.  You don't have to replace the knob and tube wiring in your house, but it is recommended because of our modern day technology.  

You can save money and do it yourself, but it is best to have a very good knowledge of electrical wiring and how it works.  If you find yourself in over your head, be sure to call a local contractor or electrician to come and give you a hand! Safety needs to be a priority! 

I hope you enjoyed this Home Inspector Secrets guide!

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