HomeRefurbers

Should I rewire my 1957 home?

« back to Electrical, Wiring & Electronics forum

Topic by dvhart posted 10-08-2013 04:31 AM 12033 views 0 times favorited 11 replies Add to Favorites Watch
View dvhart's profile

dvhart

12 posts in 2807 days

10-08-2013 04:31 AM

Topic tags/keywords: electrical ground rewire gfci

Our “new” 1957 home has most all of its original wiring and an updated breaker panel. With only a few exceptions, the main circuits are all 14ga 2 conductor wire with a braided sheath running to metal boxes. This means most of the circuits are not grounded. I have already installed GFCIs in the kids bedrooms for some added safety.

As we start in on our remodel with insulation, wallpaper removal, a new closet, etc. I’m asking myself if I should bite the bullet, rip out all the drywall, run all new electrical, insulate, and install new drywall, or if I should blow-in fiberglass or inject foam into the walls with the drywall up and leave the wiring alone. The bathrooms have already been re-wired on their own circuits with 12/2 grounded romex. The kitchen will get gutted to the studs sometime in the future and get new electrical. So we’re only talking about the bedrooms, living areas, and general lighting here really.

As I think about this, I wonder if there is really much value in replacing the wiring. First off, it isn’t knob-and-tube and the wiring is in good shape and was installed well originally. Second, a grounded circuit is only beneficial to the inhabitant if the device plugged in is grounded, and honestly, most are not. Laptops, lamps, phone charges, even large flat screen televisions – all 2-prong plugs. There is some added safety to the electrician working on the metal boxes if those were grounded, but that would be me, and me isn’t who I’m worried about there. Third, the main value the grounded circuit brings is to avoid energizing the body of a device. Having added the GFCIs, even though the body of a device could still become energized, no significant damage could be done to an inhabitant before the circuit was tripped. While the GFCI would not protect from injury should an inhabitant insert themselves between hot and neutral…. a grounded outlet wouldn’t help protect against that either.

Finally, let’s talk load. One major motivation for replacing wiring had typically been load. As I already said, the bathrooms and kitchen will get new circuits, so hairdryers and 8 bagel toasters are covered! As for the rest. While it used to be that modern living added a lot of load to the lighting circuits as we add can lights or install higher wattage bulbs… by using LEDs we can increase lumens by 5 times or so before we start to increase the load on those circuits. As for the devices we use, they are becoming more and more battery powered (phones, tablets, laptops) and those that are not are using much less power than they did even 10 years ago (LCD/LED screens instead of CRTs, laptops instead of desktops, etc.).

So with that, my current thinking is that there is little to no value in replacing all the wiring with 12/2 just to add a ground and increase the amp rating to 20A. Where I do need grounded power, such as my office, the media centers (debatable) and the garage (big power tools), I can run a couple dedicated circuits. Everything else…. I think I’m going to leave alone.

Anyone care to challenge my logic? Have I overlooked something?

-- Darren



View Dan Lyke's profile

Dan Lyke

331 posts in 3902 days

10-10-2013 02:43 PM

I don’t know about the long-term viability of the braided sheath, but I think I’m in the “leave it ‘til you’ve got the wall open” camp. However, don’t underestimate the possibility of pulling new Romex, we had an amazing amount of luck with tying string to the end of both the K&T (lighting circuits) and some of the braided (sockets), pulling it out from the attic or crawlspace, and then pulling Romex back in.

What with modern power supplies being plastic encased and having their own ground isolation, the only additional reason I can think of to want ground is that apparently you get a little more arc fault protection? Maybe just because of having an additional path to ground in the boxes. So the protection from the additional ground wire isn’t just for working on the system, there’s a little bit of safety for mechanical failure.

But AFCI breakers also provide a lot of safety for many 2 wire fault situations (if you can tolerate the false trips, our window air conditioner won’t run on an AFCI circuit…), so you probably get most of the benefit just by switching to those for your bedroom circuits.

-- Dan Lyke, Petaluma California, http://www.flutterby.net/

View dvhart's profile

dvhart

12 posts in 2807 days

10-10-2013 05:07 PM

Thanks Dan, good thoughts.

I’m starting to question my recollection on the braided sheath. I need to go check the panel and confirm that is the case.

-- Darren

View Dan Lyke's profile

Dan Lyke

331 posts in 3902 days

10-10-2013 05:36 PM

My ‘47 home that I think has had some rework before us has something that’s kind of like early Romex (all the stuff in the crawl space that goes up to the sockets, the lighting circuits were all knob and tube). Seems like it’s fine as long as you don’t disturb it too much, but I’ve pulled and re-run two segments of it so far, and am going to do the rest.

I’ve got plaster over button board, which is thick enough and has enough thermal mass that I’m not sure I gain a ton by doing wall insulation (especially in our climate), but any time I can avoid patching walls is good, so I’m big on fished wire replacement.

-- Dan Lyke, Petaluma California, http://www.flutterby.net/

View dvhart's profile

dvhart

12 posts in 2807 days

10-14-2013 05:50 PM

I confirmed that the outer sheath of the original wiring is indeed braided cloth. I also spoke with my insurance agent and there is no issue of coverage nor would there be a discount if I replaced the wiring. I imagine this concern is highly dependent on locale and insurance company, so everyone should do this investigation themselves and not rely on my experience.

-- Darren

View Dan Lyke's profile

Dan Lyke

331 posts in 3902 days

10-14-2013 06:25 PM

So it sounds like the answer for you is “leave it be”. Dang, I love when the “don’t do extra work” answer is the correct one…

-- Dan Lyke, Petaluma California, http://www.flutterby.net/

View Manitario's profile

Manitario

33 posts in 3014 days

10-16-2013 05:45 AM

I’m not sure the utility in needing to increase the circuit capacity to 20 amps; code (at least in Canada) is still 15 amp circuits, except in kitchens. The only time I’ve blown 15 amp circuits is when I do something silly like try and run a bunch of tools off the same circuit. Safety of older wiring and grounding the circuits is a different matter; personally I wouldn’t be too excited to rewire a house unless I was already pulling open the walls for another reason. I think most of the older wiring (with exception of aluminum wiring) is pretty stable unless disturbed.

View rubytorres's profile

rubytorres

5 posts in 1135 days

10-31-2015 07:08 AM

I have not tried yet.

View dbray45's profile

dbray45

158 posts in 1697 days

11-02-2015 01:53 PM

The kitchen and bathrooms should be done – without question. The other rooms may be a different matter. In my daughter’s house 1950 ish, The wires are braided copper, but when I found that she had 4 – 6 plug strips on the same circuit, this was dangerous (someone had put pennies in the fuses, many years prior). They were also running a room A/C unit on the same wires. The house was only wired for 220 volt, 60 amp service, so the fuses were exceeded by quite a bit.

We had a “heavy up” done to the service, bringing it to 220 volt, 150 amp service and a new panel. I then ran a new receptacle with 4 plugs to the living room and wired dedicated cables to the dishwasher and disposal in the kitchen. In the basement, installed a quad receptacle for the washing machine (had an extension cable to the kitchen prior) and four receptacles in the basement (same extension cable that powered the washer. The bathroom got new power with ground faults as well as the kitchen. The room A/C units got their own circuits as well.

In doing this, when we pull the walls (no insulation in any outside walls), I have circuits already there and the old ones will come out. In the mean time, they do not create a fire hazard by over taxing the old wiring.

The idea is to plan ahead and keep things safe. Many older houses did not plan for the current power loads.

-- Love woodworking and fixing most anything

View dufeo's profile

dufeo

1 post in 774 days

10-26-2016 12:51 PM

I provide links on my blog whith informations about marketing and specialize in growth hacking

View franklinbell's profile

franklinbell

1 post in 249 days

04-04-2018 11:45 AM

Wiring standards and product durability has improved over the years.
If the house is ‘47 it’s probably worth looking at a rewire.

Electrician Canning Vale
Electrician Willetton
Data Cabling Perth

View Vishal Mittal's profile

Vishal Mittal

4 posts in 172 days

07-10-2018 09:33 AM

From my opinion you should go ahead with your decision because as you are saying your house have 1957 wiring and i think now the time has came to replace them.

You are absolutely right on the installation of new LED bulbs in your house & if you wants to attract each and every one then you should install these LED as soon as possible. If you wants then you can install other new electronics gadget as well in your house like Air purifiers, Pest controller & Mobile phone network signal booster as well to increase the quality of voice calls.

-- Mobile Network Signal Booster

You must be signed in to reply.

DISCLAIMER: All views and comments posted by members are not necessarily those of HomeRefurbers.com or of those working on the site.

Latest Projects | Latest Blog Entries | Latest Forum Topics

LumberJocks.com :: woodworking showcase