Santiy check need on wirign strategy PVC/Flex Conduit sizing

felixrosbergen

Senior Member
Hi Gents,

I need some advice on quantities and sizing of conduits.

My strategy for my new construction home is to not have the building put in excessive wiring, but to have him add a LV bracket to all wall switch location and run a flexble conduit down to basement (in case of first floor) or up to attic (in case of 2nd floor). At the CATV, Cat5e location it will be the same, run a flex conduit up or down. Is this a common strategy? It seems simply, but i'm not sure how much all the conduit and brackers are going to cost me. I imagine it will be cheaper than paying an electrical to run all the cabling i want (especially since i may not use half it initially or ever). Any comments to this strategy greatly appreciated.

I don't envision doing any distributed component video or similar, it's mostly basic coax and cat5. What size flex conduit do i need to run 2 coax and 2 cat5 through one of these flexible conduits later? And what it is max size that a 2x4 framed interior wal can accept.

Then for the main runs from basement to attic is am asking for PVC conduit (probably through an interior wall). Any suggestions on reasonable quantity and sizing?

For reference this is a 2500 sqf 4 bedroom house in which is expect to do some moderate HA, for example:
- Elk alarm/automation with hardwire PIR's, etc
- Russound whole home audio
- OnQ lighting

So by rough estimate i expect to need to run the following from the basement to the ceiling at a later time through the PVC conduits
- 4x RG6QS for satelite
- 2x RG6QS or similar for XM/FM antennas
- 4x 14/4 speaker wires and cat5 for whole house audio
- approx 10 RG6QS for CATV/Sateline distribution
- approx 8 Cat5e for LAN (but could ofcourse put a switch in attic, but attic is not heated so i prefer not to do this)

I assume that for a 2x4 frame internior wall you can probably go no larger than a 2' conduit, my guess is that i will need about 4 of them. I sincerely hope they can be straight shots up from the basement.

The attic will be insulation mats, not blown in (yeah!!).

Comments greatly appreciated. I need to have all this stuff defined by monday morning.
 
IMHO, the stuff you know for a relative certainty that you are going to use, run the wires with the walls open. It will be alot cheaper and easier. Stuff you are not sure of you can run conduit I guess but you still should have the end pretty much where you think the device will go. Depending on the wire it may be pretty much break even just running all the wires, the flex conduit is not cheap. Also absolutely put pull strings in all your conduit, especially the flex stuff. Also understand it gets much hard to pull wire through a conduit as you add more. Just because a conduit can physically hold x wires, doesn't mean its going to be easy to pull them, especially the last ones. Personally I would run all the wire I thought I may use, then use conduit for the far out maybe stuff, or for extra trunk lines between floors, etc.
 
Be sure to pull pull rope into each conduit before rocking the walls. You'll find that the ridges on the flex tube (for the flexibility) sure make for difficult fish taping later. Course fishing a flex tube is better than nothing at all, but you can avoid this pain by running the pull rope before the conduit's fully fastened for easier use later.
 
Gents,

Thanks for the replies so far. Since the house is being built by a developer i can't install any of the wiring myself. I would think it's cheaper and faster for a contractor to run flex up to the attic and down to the basement from the wallplates and switchen then to run wiring all over the place. If i was able to run the wiring myself i would fully agree that flex is not the way to go.

I went to HomeDepot and it looks like 3/4" is pretty much a standard for flex conduit. It appears it will hold 2 RG6QS and 2Cat5 reasonably well. I understand it's not easy to add wires later. Either i pull it all the first time through the flex conduit or i disconnect whats already there, pull it back and then put it back in togther with the rest.

For the PVC straight to the attic, assuming it's in an interior wall (interior walls are 2x4 framing, exterior is 2x6 which the builder has informed will hold a 3" conduit) whats the max size conduit for an interior wall?
 
contractor to run flex up to the attic and down to the basement from the wallplates and switchen
Well, you keep saying flex to the wallplates and switches - but is that really where you want the wire? Or are you talking about putting your own box or mudring where you want the wire and conduit from there?
 
contractor to run flex up to the attic and down to the basement from the wallplates and switchen
Well, you keep saying flex to the wallplates and switches - but is that really where you want the wire? Or are you talking about putting your own box or mudring where you want the wire and conduit from there?


I plan to have LV brackets attached to all wall light switch locations. These LV bracket will either hold OnQ scene switches, Russoudn or similar audio keypads, or have a blank plate but still allow me to take the Cat5 from there and connect it to the adjacent switches for OnQ hardwired control.

For CATV/LAN/Phone type outlet i specified LV boxes/brackets at the usual electrical oulet level, 2 in each room.

Both the wallplate location and the other one are intended to have conduit to either attic or basement. I suppose it doesnt have to be flex conduit if you can go straight up, but i think the flex is easier to work with for a contractor.

Let me know your thought to see if i'm on the right track. I just sent off the specifications to the builder, but there's still plenty of time to change plans if needed.
 
Do you already have alarm wires being run by the builder? I would think you would want them run while the house is still frame. Also you may consider running some cat5 to the locations of your thermostats for later HA upgradeability.

One more thing, if for some reason they do not give you pull strings for your conduit, you can easily add it later by attaching a shop vac to one end of the conduit. Then tie some string to middle of a small piece (2" square) of plastic grocery bag. As long as you have a shop vac with good suction, you should be able to easily suck the string through the conduit to the other side.

Best Regards,

Rod
 
Also, remember that code calls for no more than a 270 degree cumulative bend in the tubing. However, try to keep your bends under 180 degrees for your ease of use.

180 degrees equals two 90 bends, or 4x45 degree bends.

Also make sure that you have no tight bends. All curves should be smooth.
 
"Also, remember that code calls for no more than a 270 degree cumulative bend in the tubing. "

Are you sure this applies to the low voltage wiring?
 
Thanks for the replies all...

I didn't mention it in my post, but i have specified alarm wiring for keypad, outside and inside sirens and optional wiring for all ground floor doors PIR in all ground floor room (depending on the price i may opt for wireless).

I have also asked for additional cat5 to the thermostat locations.

I put the requirements in, not it's time to wait and see what price they quote me for this stuff...hopefully it's not too high since that kind of puts the whole project in jeopardy.
 
Thanks for the replies all...

I didn't mention it in my post, but i have specified alarm wiring for keypad, outside and inside sirens and optional wiring for all ground floor doors PIR in all ground floor room (depending on the price i may opt for wireless).

You mentioned ground floor rooms. Does your house have more than one floor? If it is not much more, you may find it advantages to have them wire all doors and windows including the door leading to your wiring closet. Running alarm contacts to all doors and windows help to quickly identify if you have left anything open before you leave the house. Adding a contact to the wiring closet door gives the alarm time to call the monitoring station before the burglar has time to rip the alarm off the wall.

Best of luck,

Rod
 
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