Running electrical wire through plaster and lath?

11 Replies

Hi everyone on BP, I recently closed a 4 family house in Massachusetts in June. The house has a 1BDRM, 2BDRM, 3BDRM, and a 4BDRM. The 1 BDRM and the 2 BDRM are rented from before and are close to paying for the mortgage. I have been renovating the 2 other units the past month and have gotten a lot done. I have been researching as much as possible about running electrical wire and adding lights and outlets. I'm just starting out and I'm only 23 so I don't have a lot of reserves but I do have some credit available. I got a estimate from a friend of a friends electrician, and he came in at $2400 for adding 10-15 outlets, 4 or 5 lights, and adding 3 or 4 circuits. I can't really afford to pay that but will if I have to. I was wondering what's the best and easiest way to run electrical wires through plaster and laths. I could run some off old circuits but I'm going to have to add a couple new circuits no matter what. I was thinking about doing what I can then have him come back and give a new estimate. I also would like to cut the smallest amount of walls possible, for repair reasons. I found a way to run the wires up to the 2nd and 3rd floor but not sure what to do when I run into old plaster. Also this is an older home that has some electrical conduit in one or two rooms. So that is an option but most of the units is getting renovated, just don't want to outdate anything if I don't have to. Thank you in advance for giving any advice!

DON'T do this!!! Wiring has codes and unlikely you have the training.  If anything ever goes wrong, your insurance could be canceled and then you're really in a pickle.

Hell Ryan, 

I like your last name by the way, lol

As far I as I know the proper way to run wire is to fish it through the walls, maybe if your handy you can see what a electrician would charge just to run the wires if you supply the material ( make sure you have what's needed ) then you can install the fixtures and outlets. When it comes to electrical you really don't want to skimp considering it can cause a fire and even death if done improper. You never want that on your conscience, let along being sued for shotty work. Don't come up Short .. 

Take care my friend and maybe family, 

Michael Short  

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I believe you should have a licensed electrician do this. It might be law and there are codes that must be followed like adding "AFCI" outlets to the breaker board for every new outlet you install. Also you must be aware of your Electrical capacity load and what not. 

   If something where to happen that was caused by this, insurance probably will not cover the damage and you will be left out in the cold. Good luck my man. I know how it is to just want to do things your self but the risk isn't worth it. 

I've done some of my own electrical, when I didn't know what I didn't know.  You are going to be a landlord.  You have a duty to your tenants to provide them with a safe environment.  If there is a fire, and you have done this yourself, and there are codes that you didn't follow, you can have the claim denied, and if people are hurt, you can be found negligent.  Especially considering that you are a landlord and knew, or should have known, that this was not proper.  

When you do your own plumbing, and it fails, stuff gets wet.

When you do your own cabinets and counters and floors and wallboard and doors and windows, and you do a crappy job, it may look lousy.

When you do your own electrical and it fails, people can die.

Nuff said.

hey I'm  a real estate investing electrican haha I'm sure I can help you.  I can give you an estimate message me the details. What part of Massachusetts? And I have to agree with the group if your not licenced or properly trained you can get someone killed also although you technically can do your own e.l. work in mass it's a prosses and an inspector is especially hard on homeowners. And Mass is the strictest Code there is. The electrical code for the country was written in quincy ma.

Agree with what everyone's saying...I've worked in electrical distribution for 12 years now, and I've learned enough to do damage (I mean, good solid work) on my own house, but I would call an electrician for anything I needed in my rental unit.

Spend the money on electrical as its best not to mix copper and aluminum wiring.  That price didn't sound bad.

Repairing plaster is easy and cheap.  You can repair like drywall for the most part. Drywall mud will become your best friend!  Plaster walls was done two ways, lath-and-plaster or plaster over plaster board which is basically drywall.  The later is the most durable and was consider a premium install back in the 1930's-1950s.  The thickness of plaster will vary with systems. 

My rental has 3/8" plaster over plasterboard.  I found using a dremel worked well to grind out a recessed area to place fiberglass tape at cracks.  This allowed drywall mud to level and help eliminate the additional feathering out.   Build up mud in small increments and let fully dry before adding more mud otherwise it will crack on you, don't be in a rush.   Infill wall holes with drywall or the metal screen products that are out there.  Use a wet/damp rag to sand smooth the final finish as this help eliminate the dust. 

Thanks everyone for all the feedback. I completely agree, there's a lot of things that could happen that would not be repairable. I am going to have my electrician do the work. I will try and save money in other areas like cabinets and floors to make up for the cost.

As a LL it's either pay now or pay later and so you always need to keep this in mind when your DIYing it. Like everyone has mentioned pick the projects where you can do the least damage.

Another option is spending your time to run the wire and have the electrician do the connections. Cutting holes in drywall, drilling through joists, and fishing the wire is definitely challenging, but this isn't the dangerous part. It definitely is time consuming, so if you can do a lot of that work yourself, you'll save some on the labor expenses. Also ask your buddy if you can help him out to reduce the costs. 

To run wire, you'll need a drywall saw (~10 bucks), a paddle bit (3/4" or so), and a few long drill bits (I bought a 72" long x 1" bit for around $40 online). A 36" bit would also be nice to have. 72" bit - link to see what I'm talking about. You'll also need a fishing tape or fish poles (~20 bucks) and some electrical tape.

Youtube is your friend... 

Good luck

All this is good advice, but I'd like to point out that the DANGER!!!! stuff is a bit overblown if it's even slightly right. You wouldn't believe some of the ancient stuff I've pulled out of walls and ceilings that didn't burn down the house. Hub and spoke ceiling connections with 7 BX cables and no box. BX splices done by looping (not twisting) the 2 copper wires together and wrapping them with tape, again no connector nor box. Lamp cord stapled around baseboards for outlets, or even buried in plaster. In my old city this is stuff is pretty common, yet houses burned down by the standing electrical work as opposed to extension cords etc are pretty rare, plug in electric heaters are THE most dangerous household item by far. The most common DIY (or pro) error by far is box fill calculations, and it's REALLY unlikely to actually cause a fire. Even more so that modern loads are so light what with efficient appliances and LED lighting. One of my 1 BR units that hasn't been rewired is running on a single 20A line! And they don't blow the breaker ever.

Wiring old plaster requires planning and methodical work if you don't want to be doing massive repairs. That's why it's so expensive, and the OP's price didn't sound high to me. You cut holes for new outlet boxes using an oscillating saw. The high sand content of the brown coat will dull the blades fast. Grand floors and top floors are easy, you can drill through the sill plates to bring the wire into the wall. Middle units are tougher, you can be crossing lot's of joists.

A common way to do this without simply cutting out the whole path and drilling the joist (or cat) is to cut out like a 5x5 of plaster, notch the joist just deep enough for the cable, fish the cable through, then cover it with steel nail protection plate. I like to use 4x4 box covers rather than the usual plates, because then I can simply plaster the whole hole using Easysand setting joint compound. But most electric contractors want a whole slot opened because closing it ain't their job!

EDIT: Here's the best outlet box ever for old plaster. CDOW-TG-25. They're not easy to find, but worth it for the way they clamp the plaster in thick walls, most old work boxes are made for wallboard.

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