Safe-Off and Disconnect Circuits.

[mstrlucky74]

Looking for some help here. Want to know how to go aboutestimating hours and what’s involved tosafe-off and disconnect circuits to prep for demo. I have a pretty large floor(35ksq. ft.) that’s being completely gutted/demolished.

Does the safe-off/disconnect/tagging take place only at thepanel? Do you just shut breakers off? Do you need to trace circuits if entirefloor is being demolished? Any insight would be extremely helpful.

 

[cdslotz]

If it's being gutted, then it all comes out, right?

If so, get with the GC, or ask the GC if you're just bidding, how long will his demo window be?

If he says 2 weeks for example, give/estimate 2 men, 4 men, or how many men you think, based on density, or demo phases, and figure that many men for 2 weeks to assist the GC to make safe and verify safe for removal

 

[mstrlucky74]

If it's being gutted, then it all comes out, right?

If so, get with the GC, or ask the GC if you're just bidding, how long will his demo window be?

If he says 2 weeks for example, give/estimate 2 men, 4 men, or how many men you think, based on density, or demo phases, and figure that many men for 2 weeks to assist the GC to make safe and verify safe for removal

Thank you CD. YEs everything is coming out. You think electricians need to be there the entire time demo is going on?

 

[infinity]

Thank you CD. YEs everything is coming out. You think electricians need to be there the entire time demo is going on?

Not if all of the power is disconnected unless someone is paying for standby.

 

[mstrlucky74]

Not if all of the power is disconnected unless someone is paying for standby.

Right. Nut indo think youd want some guys there to assist woth demo. So what's exactly entailed when do a safe off and disconnect of circuits for demo/removal? If you had 2 electric closet with a few panels in each serving a floor of mostly small hvac, lighting and general receptacles what would you do If the panels where being reused and all conduit and cable was being removed by demo guys. Guess you'd have to disconnect all wires in panel since they are being reused.

 

[infinity]

Right. Nut indo think youd want some guys there to assist woth demo. So what's exactly entailed when do a safe off and disconnect of circuits for demo/removal? If you had 2 electric closet with a few panels in each serving a floor of mostly small hvac, lighting and general receptacles what would you do If the panels where being reused and all conduit and cable was being removed by demo guys. Guess you'd have to disconnect all wires in panel since they are being reused.

Yes, if you're reusing the panels then they'll need to be disconnected anyway.

 

[Smart $]

...completely gutted/demolished.
...

Completely gutted has different meaning to different trades. For example, is the HVAC system being demo'd or existing to remain. If ETR, you will not be disconnecting that circuit. In some cases, it means floor to ceiling grid. Chances are if the panels are being reused, so can some of the wiring... or the conduit. If reusing conduit only, leaving the wire in place would help e's pull in new while pulling old out.

 

[cdslotz]

Thank you CD. YEs everything is coming out. You think electricians need to be there the entire time demo is going on?

Maybe not, but my estimate would assume they were

 

[Ponchik]

If EVERYTHING is being demoed and removed, I would disconnect the feeders for the panels that belong to that floor and disconnect the conduit entries to the panels and let the demo crew to go to work.

Ask the project manger to see if they need any temporary power or of they need you to stay on site.

 

[mstrlucky74]

Completely gutted has different meaning to different trades. For example, is the HVAC system being demo'd or existing to remain. If ETR, you will not be disconnecting that circuit. In some cases, it means floor to ceiling grid. Chances are if the panels are being reused, so can some of the wiring... or the conduit. If reusing conduit only, leaving the wire in place would help e's pull in new while pulling old out.

Thanks so in the scenario that you were removing all the light fixtures and re-using all wiring. What would you do to disconnect when removing the lights? Just flip the breaker. correct? But now a step further. If that breaker/circuit fed an area outside the demo scope( say it was one office) and you had to keep the other office live, what would you do? Have to modify/temp the circuit to keep the other area active I assume?

 

[Smart $]

Thanks so in the scenario that you were removing all the light fixtures and re-using all wiring. What would you do to disconnect when removing the lights? Just flip the breaker. correct? But now a step further. If that breaker/circuit fed an area outside the demo scope( say it was one office) and you had to keep the other office live, what would you do? Have to modify/temp the circuit to keep the other area active I assume?

E.g. ceiling grid light fixtures – flip the breakers (making certain properly labeled in the panel; breaker lockouts or lift panel-end wire* wouldn't hurt), pull the fixture-end of the whips, wire nut the hot(s) and neutral(s), coil and tie-wire up out of the way.

ETR office on the same circuit as a demo office will require circuit modification, as you have surmised.

*Recommended over breaker lockouts.