Is older home electrical rewiring necessary?
wiyosaya
| Posted in General Discussion on
I am about to embark on a remodling project for my Mother’s house. The house was built in 1920, and has had some upgrades over the years.
The oldest wiring in the house terminates in two-prong outlets, and is copper wire; this is about 2/3 of the wiring in the home. An addtion done in the early 60’s was done with grounded 3-wire copper wire and is, approximately, the remaining 1/3 of th house’s wiring. Two years ago, we installed a new breaker panel.
I understand that wire ages, and that insulation becomes brittle over time, however, I am not aware of the guidlines as to when rewiring is necessary or mandated by code.
Are there any general guidelines as to when rewiring becomes recommended or necessary?
Thanks in advance!
Replies
The old knob and tube wiring and the older cloth-covered romex wiring used prior to maybe 1950 is quite fragile. It's generally "safe unless disturbed", but if you'll be remodeling around it you'll be disturbing it, and it should be replaced.
Wiring from the 50s and early 60s is usually in much better shape, but, of course, is apt to not be properly grounded. Not generally a problem for table lamps and the like, but many modern electronic devices want to be grounded. Also consider that many older people use CPAP machines and the like in bedrooms and those need to be grounded.
So grounded outlets should be installed in any area designed to be a home office or home entertainment area, and you should strive for at least one grounded outlet in each bedroom. (Also be aware of the rather perverse rules requiring ACFI breakers for bedrooms and other areas -- this may have been addressed with the new panel or maybe not.)
And of course bathrooms and kitchens absolutely need grounded GFCI outlets, as do laundry areas and outdoor outlets.
The guideline is when you're doing a major remodel don't leave anything out. You've got a new panel so it sounds like all you need is to pull new wire through the old portion of the house. Go for it, if you don't do it now it will probably never get done.
Don't replace, but don't extend the old stuff
My recomendation, and what I do on my own remodels, is to add new circuits in areas that are being remodeled and/or need new capacity, and leave the old wiring alone as long as it is not creating problems. Running new wiring to areas of the house that are not otherwise being remodeled is a major undertaking. I have remodeled and maintain 11 100 year old houses and very rarely have a problem with the original wiring. I always add new circuits for additional outlets where needed and GFIs in the Kitchen and Bath. The tricky situation is where you want to make a change in an existing circuit such as add a switch... sometimes this can be pretty tricky due to the crumbling insulation, but with patience it can be done.