upgrading electrical in 1900 house

Questions, answers and advice for people who own or work on houses built during the 20th century.

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upgrading electrical in 1900 house

Post by chris »

We are buying a wonderfull old home. It still has the electrical from the 1930's (approx). How spendy is it to completely upgrade? Is it hard to do with the old lath and plaster walls?



Re: upgrading electrical in 1900 house

Post by Shannon »

*Some* of the electrical in our house has been updated - late seventies. However, it was done shabby and we need a new box. Our electrician says we're running on power meant for a home a quarter the size of what we have.

Just to redo the panel it's about $1600.00. We have one panel with no main shut off (we're told a no no) and some fuses for the old knob and tube. To rewire the entire house (4 bedrooms, one and a half baths - 2400 sq ft approx.) they gave an estimate of $6,000.00. We're located in the midwest - so I'd assume in the northeast or other high cost of living areas the price would probably be higher.

Our electrician said they have some sort of tool to snake out the old wires and replace the new ones through the "already there" outlets to minimize damage to walls.

Anywho, haven't done this yet, but thought something we were told might be helpful. Good luck and congrats on your house!!


Don M

Re: upgrading electrical in 1900 house

Post by Don M »

Hi, Shannon is right on with her information although I would say that the estimate for replacement of the main service panel and upgrading of the service to today's standards is a bit high in my experience. Our upgrade from 100 to 200 amps and new breaker box ran about $700. The difference could be due to replacement of other wiring around the old boxes. New wiring can be "snaked" through walls and ceilings but it is tricky and time consuming; thus expensive. It is a necessity as most old houses have a 60 amp service, knob & tube wiring designed for a few light bulbs and perhaps a radio and vacuume sweeper! Good Luck, Don



Re: upgrading electrical in 1900 house

Post by Joel »

We took a step-by-step approach to it. Replaced service with 200 amp and "back-fed" existing panels making sure all circuits were protected with a fuse/breaker that was appropriate for wire size. Later, I added new circuits and replaced old as I saw fit and as renovation work allowed. House is now mostly on new wire/breaker. Cost for service was $1200 but I went underground 200 ft. to the road. Got new phone and cable in same trench. If we only could get cable down our road.... Good luck


Nancy W

Re: upgrading electrical in 1900 house

Post by Nancy W »

I am not handy with rewiring, but could not afford to pay for everything at one time. So I made a list of what I wanted in the long run. Then the electrician and I developed a plan to complete the work in stages. When we began a new stage, I paid for 1/3 of the estimate for the job, then the other 2/3 upon completion. For adding new outlets and wall switches (to rooms that had 2 entry doors but only one wall switch), I allowed him to work partial days here and there. We agreed on the time frame of 1 to 3 months to finish a stage and he gave me a better price because I was willing to be patient and be fit in between other jobs as he had time. It may not work for you, but it did for me.



Re: upgrading electrical in 1900 house

Post by Cynthia »

Yes, it is hard, it is very labour intensive and you will pay for the labour. And please be prepared to repair your lath and plaster walls because accidents will happen with those long drill bits!

A minimum 100 amp panel is your best bet, I would recommend going with something higher with lots of breaker slots. The cost of a larger panel is only a few hundred dollars and it takes the same amount of labour to mount a 200 amp panel as it does a 100 amp. This may seem like a lot but consider the price of the entire job and future considerations. I know of houses that needed a new panel because they ran out of circuit breaker slots to feed garages or air conditioners.

Rewiring a house means bringing everything up to current electrical code. Wiring a new house costs $4000 and up. All that wire, outlets and switching add up. If your house is not knob and tube, you can do it in stages starting with a service change. After you have been in your house a while, you may want to renovate the bathroom or kitchen for example and the wiring in those walls can be done in stages.

You have a lot of expenses to deal with just purchasing the house. Live in it awhile and see how things go. Take the time to find contractors that you are comfortable with, and get references. If a contractor doesn't have the time to call you back or estimate the job, find someone else. And be prepared to stick to what you want. Don't believe that because you have an old house you have to "live with it". Piece of advice: everything you do in the house will take twice as long and cost twice as much as you thought it would!



Re: upgrading electrical in 1900 house

Post by Janet »

We had our 1914 house completely rewired, new 200 amp panel, cable and telephone wires included since we didn't want to have to open up the walls any more than we had to. Added lots of new fixtures, rewired the old ones and added new outlets inside and outside the house. Cost $31,000.00 (in the southwest)! Biggest tip: make sure you have a VERY complete contract of what is going to be done and what materials will be used. Our contractor would try to say that something "wasn't in the contract" too many times. While the lath and plaster took somewhat of a beating, it is repairable, they were very good about not damaging the extensive woodwork in the house. Good Luck


Re: upgrading electrical in 1900 house

Post by dave »

I am an electrician and love doing old homes( my own included) I would be glad to assist with questions about needs, tips, and helpful hints on redoing a mess.



Re: upgrading electrical in 1900 house

Post by dave »

Would you like a reasonable quote on good work? I would travel to your home to install for fair cost. I love doing old homes RIGHT na they need TLC to do it right.



Re: upgrading electrical in 1900 house

Post by pablo »

I just bought a 1920's house and it had a mix of new wires and old knob and tube. the knob and tub was mainly in the second floor and in all the light fixtures. We replaced all the knob and tube wiring in the house. This meant some damage to the walls and ceiling. My electrician was very careful not to destroy too much but some damage is to be expected. The only danger with plaster and lath is if the plaster is in very bad shape it will crumble like a cookie when you start cutting into it...you can still patch it but it just means more work :) I was able to run all new wires up next to the vent pipe all the way up the attic. This made it easier to drop all new wires to the second floor. We were painting the entire house anyway, so whatever damage the electrician did I went behind him and patched all the holes. Make sure you get a few quotes before you proceed. The first electrician we spoke to wanted to tear out entire sections of the wall to get to the wiring!! my electrician got away with a few 4" holes here and there to get the job done and was very careful not to damage any of the wood work in the house.


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