1920's Farm house re-wire, need some input

[Verticaltrx]

I'm getting ready to do a complete rewire on our 'new' home and had a few questions for some of the more electrical savvy folks on here. I'll start by saying that I am a General Contractor and have a decent bit of electrical experience, but it's been years since I've done a re-wire so I'm sure a lot has changed since then.

Little info on the house: 2000sf 1.5 story, built in late 1920's. Wiring has been 'added' through the years with the oldest being the old fabric covered romex, newest looks to be 15-20yrs old. Some of the wiring terrifies me, I shut the main off whenever I'm not there. A majority of the connections are not in boxes and consist of two wire twisted together with electrical tape (no wire nuts). I could go on and on with the electrical horror's I've found. Anyways, the house has one bathroom and oil and wood heat. No AC unit and no plans for one. Has an electric range and electric hot water. So not a huge amount of electrical load and don't have plans for any more.


With that said, the house only has a 100amp service coming in now. It has a almost new 100 amp breaker box, which I wouldn't mind re-using, but I'm not sure if 100 amps is enough. I guess my first question is should I upgrade to 200 amp service at this point?

Second, shared neutral circuits. I'm a fan of them since it really allows you to clean up the wiring, but I've also heard of some drawbacks. What's the story on these nowadays?

What's the best way to group devices together on a given circuit? My feeling is put lights on one for a given area and outlets on another. How many rooms is it ok to group the lights together in? How many outlets? Is is still okay to use one GFCI circuit for both the kitchen and bath?

Lastly, what is the best way to cut in new boxes into plaster walls? There are a couple places I'd like to add outlets, but don't want to make a mess out of the walls. Other options for outlets besides going in the walls?


I'm sure I'll have more questions as I get into the project but those are the first that come to mind. Thanks in advance. :thumbsup:

 

[chucko]

I would say go with a 200 amp box. The number of things on each can vary depending on draw and local codes you really need to get or look at a code book if rewireing bring it up to code

 

[creekbend]

I would recommend a 200 amp service. You will have room for additional breakers for circuits in the future if you want to add another circuit. Plus, you mentioned the old Grey romex. I would definitely replace all the 12 and 14 quage wiring in the beginning and go from there. You did not mention it, but if there is any aluminum wiring present in the house or outbuildings, I would suggest that you replace aluminum with copper.

 

[creekbend]

I would recommend a 200 amp service. You will have room for additional breakers for circuits in the future if you want to add another circuit. Plus, you mentioned the old Grey romex. I would definitely replace all the 12 and 14 quage wiring in the beginning and go from there. You did not mention it, but if there is any aluminum wiring present in the house or outbuildings, I would suggest that you replace aluminum with copper.

I forgot to ask. Since it is an older structure, does it have fuses or breakers? If it has fuses instead of breakers, I would replace them right away.

 

[Verticaltrx]

Thanks for the quick responses. I will be replacing 100% of the wire in the house so that shouldn't be an issue. I like to use 12ga wire for lights, outlets, etc regardless if they are 15 or 20 amp.

 

[creekbend]

I forgot to ask. Since it is an older structure, does it have fuses or breakers? If it has fuses instead of breakers, I would replace them right away.

Sorry. I just reread your thread and saw where you mentioned the almost new breaker box. That answered my question. I'm sorry-it has been a tiring day. I must be less alert than I initially thought. Thanks.

 

[billybobjimmyjoejack]

If you are replacing all of the wire in the house you should use the correct size wire for each circuit. If you upgrade the service panel you will most likely need to upgrade the incoming feed wire and the meter base to handle the extra amperage. If the walls are plaster with wood lath and not sheet rock it will be difficult but not impossible. You can use a "cut in" box for this application and you might be able to run your wires under the house and back to the main panel. The new oscillating multi-tools would work very well for making these holes. If the walls are thin coat plaster over a sheet rock type material or regular sheet rock you would use the same "cut in" box and just cut the hole with a "keyhole" saw.

 

[Ranger Rick]

Lastly, what is the best way to cut in new boxes into plaster walls? There are a couple places I'd like to add outlets, but don't want to make a mess out of the walls. Other options for outlets besides going in the walls?

I'm sure I'll have more questions as I get into the project but those are the first that come to mind. Thanks in advance. :thumbsup:

I also have been remodeling a 1920's house with plaster walls and researched how to cut holes in plaster wall when my HVAC man butchered the walls with a sawsall cutting holes for new vents. Any way what I found out is a Multitool is what you need. The have a carbide coated blade that cuts through the plaster and a plunge saw blade to cut through the lath. They oscillate at a high speed so they do not shake the lath apart like a sawsall does. I bought the Bosch from home depot to cut the rest of the holes we needed and have used it to cut holes for a new circuit of outlets that I added. It worked great. I just read a review last night that said their blades hold up for more cuts then most of the others. Good luck on your project. Rick

 

[Tractor Seabee]

You really sound like you need some professional electrician advice. There are too many code nuances to try and design your system via this forum. If this is where you live and you have a shop I would 100% use a 200A panel. Over time you will add more circuits, guaranteed. They are cheap at the big box stores and you only buy as many breakers you need. They also have a starter kit that saves much over the indivdual items pieced out. There are some good DIY manuals at the big box stores also. Plus sometimes they have sales people who do know something. I have a few code related questions I know the answers to that I throw at them before relying on their knowledge base. Every 3 years they revise the codes and there are constant upgrades. Spend the money to get good tools especially 1/2 drill motor, 3/4 and 1" augers. You will waste a lot of time using little stuff. For a remodel like you are doing you need an auger with a 5' shank, they are flexible and will reach the double plate above or below from a 48" high switch box so you don't have to cut out the wall and they have a loop on the end to attach the wire and pull it through. I also use some light jack chain to drop down from the attic and fish it with a wire at the box location. There are old work cut in boxes that make remodel work easy. I do not reccommend using 3 wire cable for common neutral. Now you have to use a double pole breaker so one circuit tripping cuts off the companion circuit also. If you have to trouble shoot you will quickly see why I say this. Does't save that much money. Modern electronics plugged in prefer seperated circuits to eliminate feed back problems over the neutral. Do not forget about the rules for GFCIs and Arc Fault circuit breakers. Never put a GFCI in an outdoor exposed box.

Are you getting a permit? Some inspectors are really hard on DIY projects when they find numerous code issues on inspections, other are very helpful. You won't know until they inspect. Do it per code and they will recognize your quality work and breeze through the inspection.

Am I an electrician; no, but have done a lot of remodel, upgrade, and new work and stay up on code issues. I only get a permit when forced to do so.

 

[nwngunner]

First off welcome to a living nightmare. I would go 200 amp main service. So you have the option later on to add more. Now, you will more then likely have to have a new meter and main service coming in. You can use Alum triplex for this but has to be 0000 for 200amp. It is much cheaper to get alum triplex how ever most big box stores dont carry triplex in that size. They want you to buy their 000 copper and have to buy 3 times of distance of it.
I am putting new service in to my house, here in iowa you have to have a lisenced electrical contractor before the power company in my area will even put a new meter in. They also want a disconnect box out side, they are expensive as well. I am having to do a double disconnect box one size for my shop 150amp main, one for my house 200 amp.

Being that you may end up redoing the main service, you then have to pull a permit, which in iowa requires three inspections. One at main service install , 2 at rough in before drywall is up, 3rd is after your all done.

All of your outlets will have to be the new tamper resistant. Also code here requires an outlet at every outside door. The outlets have to be in a sealed weather box, and have a wr "weather resistant" tr "tamper resistant" gfci.

I am not sure how many outlets can be on the same circut, how ever i do know you have to have outlets every 6 feet. How ever i think that applies to new construction only.

Any outlets with in 6 feet of water have to either be gfci outlets or be on an gfci breaker. Also any basement out lets have to be gfci as well. In my basement, i have a sump. That does not have to be gfci, requires a single uni outlet. Same if you have any freezers. Otherwise any other outlets have to be gfci. All bedroom outlets have to be arc fault.

I hate it as well where you are required to get all of this expensive crap, how ever like the tamper resistant outlets are required now. If you ever sell the house and some one gets shocked or electrocuted from putting something other then a plugin, in the outlet you are liable.
Gfci outlets are EXPENSIVE, arcfault breakers are EXPENSIVE shop around and check ebay.

Also in your basement if you have a basement, any wire hanging below the floor trusses has to be in conduit. So every where you can drill though and keep ever thing up out of reach.


Also more then likely, if you are forced to get a permit, expect the tax officer to be out to check out your house. Only reason i know what i do at this point is i have had an electrician out to do a ton of work on the farm and in two houses, i have asked questions and payed attention.

All i have to say is good luck and be safe.