Running new wiring in old houses.
ahneedhelp
| Posted in Construction Techniques on
Hello –
I would like to add trim or bumped out walls to the surface of existing plaster walls to run new wiring and mount outlets.
The house does not have baseboards so I have an opportunity to tuck the wires behind new baseboards.
Local code will not allow me to mount conduit onto the walls in residences.
Then I recall something about minimum height requirements for outlets.
This may not allow the outlets mounted on baseboards.
Anyway, does any of this sound like too much trouble for wanting to avoid having to cut into plaster walls and fish wires ?
Many of the existing outlets will be updated as well – wire will have to be pulled for those.
Thanks for your help,
Alan
Replies
Yes, it sounds like too much trouble.
Cut in for the boxes. Use old-work boxes.
Use a mirror and bright light (or a fiber optic
probe) to look inside the wall. Use a long
flexible bit to drill through blocking and plates.
You go in through the outlet cutout. May need an
extra access hole here and there. Just patch them.
Don't drill through anything important, like pipes.
Use a "hot stick" fiberglass fish to pull the cable.
Beware of any walls that may contain plumbing. USe
a magnetic probe to find hot wires and avoid them.
Maybe $200 worth of tools there (not counting fiber
optic stuff). An hour or so per outlet. Compare
with a hundred sheets of drywall, tape, mud, paint,
mess, etc.
"An hour or so per outlet."
Or hire a cable guy to show you how to run and drill. I had a cable modem installed and he was very fast and good (being paid by the job will do wonders for the efficiency!)
Bob:
The cable guys in these parts (Comcast) are notorious butchers. It's common to see cable wires coming out of brick exterior walls on 2nd floors, then run down the side of the building(sometimes zigging and zagging) to the cable junction.
Generally they start from the inside and drill till they see daylight. If they hit brick they change to a masonry bit and keep going. Again, its not uncommon to see chunks of brick broken off from these guys drilling from the inside out.
Maybe your cable Co. pays more than minimum wage.
Craig
Yup, I have a place where one of those morons drilled down thru the floor, hit a joist, and just kept going straight down all the way thru the middle of the joist.
-- J.S.
We have THREE different entry points in our brick wall from previous installations. (Yanked out the cables and plugged the holes.)
We also have a line running along a wall and then up into the attic through the soffit.
Then it comes back outside on the other end and down a wall before it enters the house through the wall.
I've seen too many examples of caveman cable installations over the years. Total hack jobs.
Alan
"Maybe your cable Co. pays more than minimum wage."
Piece work around here.
Now that you mention it, maybe the fact that I told him I do home inspections and went down in the crawl and helped him thru the really cruddy part of my crawl helped avoid the butcher work!
If it was mine I would cut off the lowest 5" or so of plaster/lath, put the outlets in the baseboard using plastic adjustaboxes (confirm with code - no problem here) and install new baseboards - 1 x 6 with basecap and shoemold - check door casings to make sure they project enough to receive 3/4" base. There's nothing like a continuous raceway.
T. Jeffery Clarke
yup, there's about a million ways to run new romex thru old walls, and a lot of great tools to make it possible - many of them not easy to find at the big box stores. A lot of the tools are pretty simple things, but until you see them used...
Doing it really does look like magic when you get to see an experienced pro at work.
Those who don't know how, always say "it can't be done".
It can be time consuming, and quite frustrating, but it is also hugely gratifying to successfully install an outlet or a fixture where you always wanted one and finally learned how.
And have no plaster damage in the process.
And to have wiring that you don't have to wonder about / worry about any more ("I think it is safe, but don't really know").
Successfully adding outlets (that work) with no major wall damage earns a lot of wifely gratitude. ...that's not a mistake, it's rustic
Also get yourself a diamond blade hand grout saw. They're inexpensive and perfect for cleaning up those places where the router can't reach. They cut plaster so easily that if I'm just making a hole for a box, I do it by hand -- easier than getting a power tool out.
-- J.S.
Thank-you so much to everyone who replied to this thread.
Every advice and humor is appreciated.
Some walls will have to be dealt with the old fashioned way but there are plenty other spots where the wires can be tucked behind new or old trim.
I am looking forward to trying many of the techniques offered here.
But not too thrilled about working in the attic where I will be installing new junction boxes and wires back to the new panel.
We're finally easing into summer weather.
Alan
Please be careful.
If you can schedule it try to do the attic work between 9PM and 9AM. Your brain cells will thank you. Wear a thin long sleeve shirt with a tight weave to keep the fiberglass out. Throw your hand tools and small part in a zipper bag. Klein makes a heavy cotton one that's good.
I had forgotten about the small grinder with the Diamond blade on it. We got one long after I did my last chair rail type rewire job. It would probably work better than the router for cutting the grooves and is now the tool of choice in cutting in the boxes in plaster-lath. Be careful with the grinder. It doesn't have an easy depth stop, maybe you could rig one, and will do a number on plumbing, wiring and anything else it hits.
Best of luck to you.
Thanks, 4LORN1 -
I ordered five Tyvek jump suits and full headshield that has elastic cutout for respirators.
I have very little tolerance for anything that makes me itch.
(Attic work will be done long after the sun sets and the roof cools down.)
And, yes, the grinder may turn out to be the most handy tool for this dealing with the plaster walls.
Have a great weekend.
Alan
I prefer the morning because it has all night to cool down (that damn thermal mass holds the heat way past the sun sets, usually).
If there is any way you can get a fan up there use that too. Mega helpful (not just for temp, but also have it draw air AWAY from you and dust will be much less trouble. You will discover that your body is much more sensitive to cool air drafts than you ever realized, when you find little air leaks in your roof that let the suprisingly cool feeling 90F outside air be drawn over your 120F heated body (ask me how I know) by that lovely fan.
:o)
An alternative that may save your back is to Install a new chair rail that will cover a wiring chase.
1) Figure in which rooms and how high a chair rail will go. Not every room needs to get railed. Not every wall face needs a rail cut but every wall that will have an electrical outlet, switch or receptacle, gets a rail on one side or the other. Also although this method is based on installing a chair rail, to simplify patching the hole, you can patch the wall with plaster or drywall. This works well if you are parging or adding textured plaster to the wall later. Some wallpapers also can help disguise the patch job.
2) Mount a cut guide temporarily to the wall. The specific height will depend on the height of the rail and the model of router you use.
3) Using a router with a carbide straight cut bit set to the depth of the stud face. You need to cut a 1-1/2" wide groove through the plaster. In dry wall, or plaster on gypsum backer board you could make two cuts with a 3/4" bit. With plaster-lath a good 1/2" bit , not so good maybe because you are likely to burn through a few of these, and making two cuts 1-1/8" apart and tear out the center with a hammer. Go slow on the cuts to avoid loosening the rest of the lath on the wall.
4) Lay out and cut in the boxes. Wire to the empty holes. With the groove cut in the wall at chair rail height switches are only a foot or so away and receptacles only 2 feet or so down. Even a run to the attic is no real problem as the bays are completely open making a cable dropped in from above easy to see and grab. Drilling between stud bays is simple with a sharp spade bit but a long spade, about 2', makes the holes straighter, easier to pull cables, and a bit easier to shoot in the center of the studs. If you can center the holes you will preserve the strength of the wall and avoid being forced to use nail plates.
5) Mount and wire the boxes. Make them live and check the circuits. Install nail plates as needed. Plates are not a bad idea even if not required especially if the person doing the rail installation is new to the practice.
6) Usually I'm able to hand of the rail installation to a friendly finish carpenter. With practice and a known substrate The groove can be cut as wide as the chair rail and the rail attached directly to the studs without modification. Another method is to route rabbits on the back of the rail to cover the plaster cut and still allow the rail to contact the studs. Alternatively the rail can be nailed in over the plaster. Not being a carpenter I give these as ideas that have worked only.
Note: Cutting a groove all the way around a room with plaster-lath walls is noisy and messy. Using an old router and tarping the floors is advised. Wear a good dust mask and hearing protection. Watch the cut depth. This is an adaptation of the same general technique done with baseboards but this one gets you off your knees and saves your back while shortening the distances you need to snake the cables. Better all around when it can be used. Another arrow in your quiver of techniques.
I am going to start cutting into some of the plaster work for access.
I can borrow my friend's grinder which he has been using for the same reason at his house.
I'm also interested in using the Fein (is it the multimaster ?) with one of the special blades. I've heard the Fein may kick up less dust ?
Thanks for any feedback.
Alan
Alan - The Fein is too slow for lots of production cutting (I have one). Depending on your approach did you consider a circular saw with a carbide edged cut-off wheel? I just used this setup to cut 40 pieces of rebar in about 30 minutes - it was a breeze.
T. Jeffery Clarke
Quidvis Recte Factum Quamvis Humile Praeclarum
Edited 6/5/2002 3:30:50 PM ET by Jeff Clarke
I'm currently doing a major kitchen renovation in an old house where plaster walls had to be removed as part of the overall redesign, and all new services run as well. I used a professional grade jig saw with a carbide blade to cut into the plaster and lathe, as it was light, I could control the blade speed, and not damage framing that wasn't coming out. I used lots of blades - one every 10' or so of cutting. Dust control is a major issue with plaster. Tape and seal everything with plastic, and wear a respirator. Contain the dust, and don't let helpers walk in and out of the room while you're working. Enjoy the day!
> Dust control is a major issue
Another trick: have the shop vac running and aimed right at the point where the dust is being created. Grab as much as you can of it as soon as you can, and the problem is much smaller. This can be a nice job for a child who wants to help.
-- J.S.
Sorry, John - dealing with lead-paint-bearing plaster dust is NOT a job for a child. It is a job for a well-protected adult that understands what to wear.T. Jeffery Clarke
Quidvis Recte Factum Quamvis Humile Praeclarum
Going back to the original post, please explain this: "Local code will not allow me to mount conduit onto the walls in residences". What is the reasoning behind this?Richard James Tolzman
Don't forget that the wiring needs to be covered by at tleast an 1.25 inches or it needs a metal plate protecting it. It's awful easy to do things "half assed" but isn't worth it in the long run.
Good luck
RE - Don't forget that the wiring needs to be covered by at tleast an 1.25 inches or it needs a metal plate protecting it. It's awful easy to do things "half assed" but isn't worth it in the long run.
-----
Thanks for the reminder.
This will be a fully permitted and inspected work.
Nothing "half assed" about it.
Actually, I tend to overdo things beyond what the code calls for.
Techniques that come from experience is what I am still learning, as most in the business continue to do so.
I appreciate all the pointers given in the thread as they have put me on more firm footing to get the project rolling this week.
One day I hope to be able to dish out useful advise as others have for me.
Alan
Hello -
Please read a new thread I created under the heading "Q on removing hotwater baseboard" (21748.1)
I am trying to gain access behind baseboard radiators for routing new wiring.
Thanks for taking the time,
Alan