Knob and tube wiring

9 Replies

Hey everyone, rookie here.

I’m working on finding my first double I can house hack and add some value to with my boyfriend. I found one that was built in 1912 that has knob and tube wiring and some exposed updated wiring. We haven’t put it under contract and had and inspection yet but the electrical seems to be the biggest issue. I was looking for some people’s experience with updating electrical in their rentals and maybe some ideas on the cost. And information would be greatly appreciated!

Recently had an electrician give me a typical cost of $4000-5000 to completely rewire a house. This is in TX. I recently did one myself in 2-3 days with a few hundred in materials.

@Ashley Martin I think it would depend on a lot of different factors such as how much knob and tube wiring there is, your market etc. But it can definitely become very pricey. I ran into this on a potential property and the estimate I received was $9250 for a remove all the knob and tube wiring and update.

You will want to check with your insurance company. I looked at one a couple years ago with knob & tube and my insurance company would not cover it with K&T.

If the knob & tube is in decent shape you can usually work around it, so long as you don't run afoul of your insurance company or your local electrical inspector. Most people don't want to buy a house with K&T so you will run into plenty of issues trying to sell it if you don't plan to keep it as a rental.

Rewiring in my area runs about $3k, but that doesn't include the cost of a new panel and I haven't had to do a rewire in a while - and NMS wiring prices have gone through the roof. I just bought 250 feet a couple of weeks ago for $140. A year ago that same wire cost me $80. So you can probably add at least $1k upcharge just for materials right now. 

Originally posted by @Eric James :

Recently had an electrician give me a typical cost of $4000-5000 to completely rewire a house. This is in TX. I recently did one myself in 2-3 days with a few hundred in materials.

 It is worth checking local code. It sounds fine in TX, but in my city you can only rewire your personal residence without an electrical license. Investment property here requires an licensed electrical contractor for any electrical work - even for the owner to do. I am guessing it varies around the country. 

We do not have a choice. Insurance Carriers & Building Inspectors deny coverage & inspection approvals on K&T & old ungrounded circuits.

I did one myself & as @Eric James said it's a couple of days work & for me $400-$600 with an upgraded service feed, upgraded panel & all new wiring to ALL new outlets. Also here many circuits required 12/2 ga. GFI outlets & appliances require dedicated circuits to the panel. Furthermore any new circuits here require AFCI breakers that 'break the bank' to purchase. Some guys put them in & then take them out after the final inspection. Given what we wanted to do & the code requirements an electrical contractor quoted $6k for the complete rewiring, so I pulled the permit & did it myself.

Also here the Building Inspector has to approve & sign off on the permit & electrical inspection before the utility will reconnect.

It depends on how easy it is to access. If it's in an open basement, much of it is pretty simple. It's harder if it's finished basement, crawlspace or slab. We rewired a small house for about $5000 or $6000 recently. 


The Knob & Tube wiring will be an issue for insurance.  We many Insurance companies and both for Homeowners and Dwelling Fire (rentals) Knob & Tube or Aluminum wiring will cause them to decline the policy.  I would figure in the cost of rewiring in your calcuations (not just the visible but all wiring changed from the Knob & Tube).  Even if you do get Insurance, it will impact your resale later if you customers cant get coverage.

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