Putting a hole in a wall without getting electrocuted.

DirtAddsHP · 04-22-2009, 03:41 PM

I need to install ventilation in my server closet at home. Which requires me to put a hole in my wall for the tubing. But i have no idea where the wires inside the wall are. I have a stud finder but im not sure if that will help with conduit and wiring.

how do i find where the wires/conduit are?

RegeSullivan · 04-22-2009, 03:51 PM

Some stud finders will locate AC in a wall. It will usually tell you on the device if it has such a feature. I do not trust them so I usually put a small hole in the wall and look around in the wall cavity with a mirror and pen light. I also have a small camera system with a USB powered LED I rigged that I can stick in the wall using my laptop. If this is an outside wall you will have insulation to deal with also.

Rege

Willie T · 04-22-2009, 04:56 PM

It's not possible to use the wall stud bay, just as it sits, as a plenum?

RegeSullivan · 04-22-2009, 05:07 PM

WilliT,

I think you are suggesting or asking if using the stud bay without some kind of duct is possible. That would be a fire hazard in most cases. I know this was common practice in older homes but I believe it is against code today. Perhaps one of the HVAC guys could verify that.

Rege

Willie T · 04-22-2009, 05:22 PM

I know that entire ceilings and floor spaces are used across hundreds of square feet of office areas for air supplies and returns in many commercial applications. If you are venting the closet to the outside, it could turn out to be allowable, maybe???

DirtAddsHP · 04-22-2009, 05:28 PM

Quote:

Originally Posted by Willie T

I know that entire ceilings are used across hundreds of square feet of office areas for air returns in many commercial applications. If you are venting the closet to the outside, it could turn out to be allowable, maybe???

no i have a window mount ac a few feet from the closet, so im just running ducting from the AC though the soon to be hole in the closet.

DirtAddsHP · 04-22-2009, 06:19 PM

so i need to drill a 1 or 2" hole and stuck a mechanics mirror with a penlight and poke around?

220/221 · 04-22-2009, 06:36 PM

Quote:

how do i find where the wires/conduit are?

Cut a hole and look in there

You are just cutting with a hand held drywall saw....right?

Use some logic and finesse and you will be fine. Make the first cut inside the closet so a patch wont be evident incase something is in there.

DirtAddsHP · 04-22-2009, 07:03 PM

Quote:

Originally Posted by 220/221

Cut a hole and look in there

You are just cutting with a hand held drywall saw....right?

Use some logic and finesse and you will be fine. Make the first cut inside the closet so a patch wont be evident incase something is in there.

ill have to find a handsaw, i was gonna use a sawzall or something.. and good point about cutting the first hole on the inside, thats smart.

Yoyizit · 04-22-2009, 07:10 PM

Usually the Romex is protected by a nailing plate.
There is an expensive device called DrillStop or something that cuts the power to the tool.
Use a hand drill to drill the hole, in any case. It gives you better feedback as to what you're hitting.
If you do hit a cable, the drilled hole acts like a barrel so that the sparks are thrown out horizontally.

Looks really cool. . .

If you're using a grounded tool you won't get a shock but it may trip a breaker. If not, stand on an insulator like wood or carpet or have rubber shoes on.

jbfan · 04-22-2009, 10:55 PM

Quote:

Originally Posted by DirtAddsHP

ill have to find a handsaw, i was gonna use a sawzall or something.. and good point about cutting the first hole on the inside, thats smart.

Nothing spells disaster like a free running sawzall without know what is behind the drywall.
Buy a drywall saw for a few bucks and save much grieve later on.
Is there anything that makes you think there may be electrical in the walls?

Chemist1961 · 04-23-2009, 06:59 AM

I run 2" vac pipe in blind walls frequently. Hope this helps.
Find your preferrred joist bay and mark you studs, Check the oppoposite side of the walls for receptacles. Generally if receptacles are strung across a wall the wiring will run at a height of 14-18". If they are fed from above or below they will enter and exit the wall within 1" of a stud and should be secured to it.
If you drill a fine marker hole in the closet floor at the stud location to the basement below you can inspect for wiring running from below in that joist bay. Also inspect your closet area for switches running up the wall to over head lites.
I do use a stud sensor with AC detector.
When I have to cut blind and can't inspect from below I drill a small circle of shallow holes at my centerpoint with a 1/8 masonary bit. Then do a shallow cut hole to hole with a knife. This alows me to perforate without slicing blindly into hidden wires. I then fish in a hooked coathanger and pull gently in several directions. If necessary feed in a mechanic's folding mirror or Rigid SEE SNAKE.
This should get you through the worst.

Chemist1961 · 04-23-2009, 07:04 AM

Here is another thought don't know your heat and venting requirements requirements. What about a transfer grille setup. Cut into the bottom inside your closet. Then the top of the same joist space from the outside. This is called a transfer or transition? in Hvac to help vent an unvented room to the nearest return air vent. Post a note on the HVAC forum for proer details and you're away

DirtAddsHP · 04-23-2009, 11:00 AM

Quote:

Originally Posted by jbfan

Nothing spells disaster like a free running sawzall without know what is behind the drywall.
Buy a drywall saw for a few bucks and save much grieve later on.
Is there anything that makes you think there may be electrical in the walls?

nope i have no reason to suspect.

**Termite** · 04-23-2009, 03:51 PM

Just use a keyhole saw and go slowly and carefully. Avoid sawing right up against the studs and you should be fine. Using a sawzall won't allow you to feel what you're cutting into whereas a handheld saw will. This isn't a big deal and will likely be a piece of cake.