Author: David Feller,
This is the fourth installment of a multi-part series covering all aspects of low voltage wiring in the home: entertainment, security, automation, and future planning. A new section will be published every few weeks.
Table Of Contents:
Chapter 5: The Actual “Pull”
Whatever systems or wires you choose, these general rules and procedures will make the job easier.
- Most important: After you get through wiring, go through the entire home with a video camera filming every square foot of every wall and every ceiling. Having easy access to this (storing the file on your computer or DVR) for later access is a HUGE benefit to later trim-outs.
- Coordinate with the builder (See chapter 2) and the local inspector before you start any work. Make sure you are in communication and coordination with other subcontractors, especially electricians and other house systems. Getting your wire ripped out or holding up the project are both killers.
- Don’t confuse pre-wire with future proofing with conduit. While the walls are open, run wire outside the conduit and leave the conduit empty for later.
- A combination of buying unique colors for each system (Ethernet, phone, home automation, cameras) and clear labeling as you pull wire will is critical and can save countless hours of finding the right wires later. Be sure to use the right kind of label for each wire so they stay put.
- Use proper wire types – in wall rated types when you purchase. Truth is that few inspectors will even glance twice at low voltage cable but better safe than sorry.
- Careful and organized documentation is key. Best is to get a copy of the blueprints and create one electrical and one low voltage set of prints. Each room should be clearly labeled (Bedroom 1, Laundry etc) with each drop whether it is trimmed out or not clearly labeled and color coded. Use a different color pencil for each type. e.g. BR1-TV1, BR2-phone1, BR3-data1, Living-spare1 and obviously make sure both ends are the same. Make sure the labels used on the wires themselves exactly match the labels in the documentation and you choose the right labels for each wire type so they do not come off. Consider that the home will be around for a long time and the labels need to securely stay in place the entire time. My favorite are the ones printed on slick plastic/paper and then shrunk onto the cable. Some choose to also put it all in a spreadsheet for the larger installations.
- If you have a multi-story home, make absolutely sure that at a minimum you have a chase or large conduit between attic and basement and/or each accessible crawl space.
- In each room, use “mud rings” – they are generally orange and have a connection point for conduit but are open in the back.
- Heights: Most will go at “outlet height” which frequently is the length of the electricians hammer from the floor. Those for speaker controls and Home Automation switches are at switch height, and those for keypads and displays are generally 10-12” above switch height. (You don’t want to bend down to switch height to change your favorite tune).
- Locations: This is a good opportunity to engage the wife – where will the bed go? Will the computer be on a different wall? The standard practice of pulling all your wires for a room to a single location often leads to compromise. Mud Rings are cheap – get the connections right where they need to be in the room.
- For flat panel TVs, typically, the pre-wire runs go to an associated source component location with a big 2” or larger empty conduit run from the source component location to behind the flat screen. Even in bedrooms if you can.
- Use pre-construction guides for speaker locations. That gets the hole in just the right place, a spot to tie the wires, and the drywallers don’t just cover it over. If you can’t find cheap guides, carefully record the location and attach the wire to a nearby joist or stud then take very good pictures/video of the locations so you can cut holes in the right places after drywall is complete. See Chapter on whole-home audio as frequently a box is built and serves as the mounting location for a ceiling speaker.
A possible source: http://www.crutchfield.com/g_32300/In-wall-in-ceiling-Brackets.html?tp=1165
The Media Cabinet:
Yes, it is part of the pre-wire normally:
- Choose a good location for your wiring closet/media cabinet. Once you consider all the equipment you need to install, and decide on how big of a cabinet you need, you can properly place racks and cabinets to maximize access to chases and insure you minimize wire crossovers and proximity to electrical wires. A central location will minimize individual runs. Make sure you have thought through cooling – if you are going to have a lot of equipment, consider adding an A/C vent and return to this room.
- For smaller installations 6-8 TV locations, phone and 6-8 Ethernet locations, a single 30” (ish) high “between the studs” On-Q or other readily available media cabinet from your local home improvement center will work just fine. Look for one with a good fastening system (modules that will easily snap into pre-drilled slots/holes), that it has space for an electrical outlet or two on the bottom, and some nice door or cover. Consider going either a metal back and glass front or all plastic to accommodate future or imminent wireless devices
- Shoulder height for easy working is preferred. You will spend quite a bit of time punching wires here.
- For larger installations, buying 2 or three identical cabinets and putting them side by side is the “next up” option. Put cable/Satellite in one, Ethernet and Phone in one, and keep expanding as you need.. Consider putting a 1/3 height rack below the media cabinet for back room equipment (Audio sources, matrix equipment etc.)
- If you end up needing more than 2 of these boxes, you should consider graduating to a rack system entirely. Racks should be at least 24” out from the wall and feature highly organized and separated patch, routing, and source equipment sections.
- The bigger the install the more organized and precise you need to be with trimout.
- Note that if you are doing structured lighting, keep it WELL AWAY from your media cabinet .
- Make sure you have dedicated electrical for your media cabinet
- Consider cooling if you have ANY source equipment here.
Coordinate with your Electrician, LOTS to think about:
Unless you really know what you are doing, and preferably have both professional training and a license, leave the high voltage stuff to the professionals. Yes, it looks straightforward but there are just too many codes and good practice items to cover in a document like this. A decent inspector can spot an amateur job a mile away and will most certainly give any such job undue attention – for good reason. That said, there are quite a few things that should be considered and specific instructions given to the Electrician:
- Use the deepest non-metallic boxes possible in each location, especially switches, but also key outlet locations. Deeper boxes cost a little more but will provide room for future upgrades to home automation systems. (Non-metallic so that future RF switches will work properly)
- More plugs, bigger wire. An electrician looking to meet code and keep your costs down will go with 15A (14Ga) wire/circuits and fewer outlets per room. If budget allows, go 12Ga (20A, yellow) circuits everywhere. Instead of letting the Electrician randomly choose outlet locations (to code), go through and plan each one yourself alongside the Electrician.
- Consider specifying dedicated circuits to media locations (home theater, main TV location, media cabinet etc.) Clean(er) circuits will be appreciated later. Also consider power conditioning devices (and surge protection) at a minimum on those circuits but preferably home wide. Modern devices can actually clean up the power as well as providing surge protection.
- Consider specifying that lighting and outlets be run on separate circuits for each room. Depending on the type of room, multiple room’s lights can be run on the same circuit. Fluorescent lights are noisy and best separated from other devices if possible, and when you blow a breaker you will not have to find a flashlight.
- If you are building a new home and have a little flexibility, consider adding some extra circuits to your plan – choose the ones that fit you and your hobbies/lifestyle – all are much easier and cheaper now:
- Christmas lights – an outlet under the eaves of each floor every 40 feet all on the same circuit wired to a lightswitch near the front door. Don’t forget to take a cat5e cable to that same location for future Home Automation control. Consider placing outlets around mantels and on “high shelves” where extra lights/decorations are frequently placed. Near each banister for lighted garland.
- A dedicated 220V outlet near your workbench (garage, shop etc) for future welder or big compressor
- Dedicated 20A or 30A 4 gang outlet to same garage/shop location. Lots of tools put a large draw on wiring.
- As for the garage in general, overwire. There are typically only one or two outlets, have them treat it with the same rules as inside the home.
- Lots more outside plugs – I have two on each side of the house. Good for kids birthday blow up houses, bush trimmers, etc.
- Landscape lighting – a dedicated 20A outlet where a transformer can be placed for landscape lighting
- In-landscape plugs for “future additions” – I ended up adding one in back for a pond pump and one in front for a water feature
- Circuit for future extra freezer/fridge – garage, butler’s pantry or storage areas
- Accent/reading lights on either side of the master bed – I added a switch and 6’ high sconce on each side retrofit.
- Extra 2 dedicated circuits for master bath Jacuzzi tub – you need one for pump and one for heater usually.
- Extra GFCI protected outlet near “critical” toilets – I’m particularly fond of the Japanese style heated jetted toilet seats myself, but perhaps that is a personal preference.
- Whole-Home Surge and Power conditioning: Usually done at your main panel, you should at least consider one of the whole-home systems on the market. Marketing claims include not only surge protection but the ability to lengthen the life of any electronic device in the home by providing it “clean” power.
- Circuit for a future whole-home attic fan – would include a switch near the fan.
- Floor heaters – Cold tile can be fixed but requires another outlet low in a bathroom and a control panel at switch level.
- Big yard/play area? Consider an extra lighting box or two that can support big floodlights under your eaves to light up that trampoline or pool on a separate switch from the normal back-porch lights.
- Don’t forget wiring for sprinklers – usually an 18ga stranded cable with 9 wires (8 zones plus ground) from the timer location to the valve box (distributed valves – of which I’m not a fan) require a different wiring setup. Make sure to install a cat5e to this location for future home automation and another to an outside eave for rain detector.
- Cold climate? Don’t forget to plan for roof edge heaters, heat tape around external pipes, and head cord for downspouts. A heated driveway (usually hot water driven) is about the best gift a guy that hates to shovel can get.
- Extra Lighting:
- Under cabinet lights especially in the kitchen and craft areas
- 3 wire Romex to each ceiling box for future ceiling fan installation (See chapter on what to avoid)
- Future electric thoughts:
- Dedicated outlet/circuit for electric car charging in the garage
- Prewire for solar panels
- Prewire for generator (This could be a chapter all in it’s own as you will need a special subpanel and switchable circuits – consult a professional for more information)
This might actually be the easiest part. There are a few things to consider however:
Prepare the spools
- Choose the pull style
- Coax is typically on rolls and you should build something to hold it so that is comes off easily – You can buy a stand like this http://www.action-electronics.com/wirecable.htm Or get a 1” galvanized pipe and some “U” pipe clamps, feed the pipe through the center hole in the roll and screw the whole thing between a couple studs. Get a long enough pipe and you can suspend 5 or 6 different spools (different colors) in your wiring closet for pulling.
- UTP (Cat5e/6) is typically sold in pull boxes that dispense the wire without kinking or twisting. They do like to float around the floor however, so consider lining them all up against a wall and duct taping them together and to the open studs of the wall
- Other station wire generally comes in rolls/spools – consider a smaller pipe but mounting to a wall like the coax.
Plan the ends
- You can certainly group wires to each room/location, but once you get down to the media cabinet/wiring room, they should be grouped by function.
- Ideally each function would be a different color wire for organization reasons. Coax and Ethernet is available in varying colors, grey, white, blue, red for instance.
- All “field wires” – the ones running to each room, should be punched down in the wiring room/media cabinet and then use patch cords to take the connection where you need to so make sure you leave enough extra wire in the wiring closet/media cabinet to accommodate sorting and terminating. Generally, we recommend, if the media cabinet is mid-wall height, to leave enough extra to touch the ground.
Keep Wire in walls
In the room itself, it is common practice to run the wire through the top ring of the mud ring, loop it and then continue “out” the bottom ring. Better to leave the loop of wire in the wall instead of having a drywaller cram it all back in himself. A small piece of electrical tape can hold it in place as necessary. Leave about a foot of wire that will hang out the mud ring to make termination easier later.
Plan the Run
- Avoid running wires in conduits, or in A/C vents or returns. Special plenum wire is available if you must but if the walls are open – don’t.
- Avoid running parallel to electrical wires for more than a foot or so – noise can conduct across. Always stay perpendicular to electrical wires where possible. Stay at least 18” away everywhere possible, depending on the load on an electrical wire, it puts out an emi field for about 18”. Completely avoid larger electrical cables like to the stove, A/C unit, or main feeds in SER cables. They tend to have higher loads and will cause more noise. Speaker wires and A/V cables are most susceptible, but even coax and data cables can pick up noise. Twisted wires tend to fair better with noise, an unproven trick is to put a twist on untwisted wires where they are near interferers.
- Same rules apply on how much wood to cut as with conduit –
Load Bearing members (if the member carries the weight of the structure above it):
- A hole can be up to 40% of the width of the member if it is centered.
- A notch (a cut out from the side) can be up to 25% of the width of the member.
NON-load bearing members
- A hole can be up to 60% of the width of the member
- A notch can be up to 40% of the width of the member
If your walls are 2x4 walls (actually 3.5” wide):
If it is load bearing your hole can be 40% diameter 3.5”X.4= 1.4” or a 1 3/8” hole through which 1 ¼” OD conduit will slide.
If it is non-load bearing your hole can be 60% diameter 3.5”X.6=2.1” or a 2” hole
If your walls are 2X6 walls (5.5” wide) the same math applies
Load bearing up to a 2.2” hole
Non-Load bearing up to a 3.3” hole
- Get an auger bit – a 1” will take care of most of your needs – they pull themselves through studs and caps like butter.
- DO NOT drill through or cut structural beams (Laminated or pressed for instance) or put new holes in wooden Ibeams without specific permission from the builder and an engineer. Most I beams have partially drilled holes you can knock out with a hammer but try to stay 12” away from places the I beam is supported. If you violate these rules, it is possible that some building inspector will force the builder to replace a beam – at your expense.
- Allowing wires to rub, kink, or have excessive pull pressure applied is generally very bad and can decrease the capability of that wire or damage it to uselessness. Do not let coax get bent into less than an 8” radius or it needs to be replaced. It Ethernet wire is kinked it needs to be replaced.
- If your runs are not fairly straight and easy to access, consider pre-measuring and laying each run out before you actually start the pull
- A helper in the basement (media cabinet) is a huge help getting wire off spools smoothly and into the first hole.
Secure the Wire properly and finish per code
Be sure to strap wires as is done with electrical wires. A Strap within 12” of a mud ring, within 12” of a joist penetration, every 4.5’ vertically and every 6’ horizontally is reasonable. For just a few cables, zip ties with a screw hole and a drywall screw work very well. For larger “main” runs, a piece of Romex stapled at each end to a joist that droops to form a big U makes a nice horizontal hanger for attics and in horizontal chases. Home Depot and Lowes both sell a very nice staple gun that shoots out big staples with plastic bridges just for this purchase that can greatly speed things up.
- After you finish, seal all the holes with a little spray of expanding foam for fire purposes. No holes can be left around wires through studs, top caps, or joists.
- As a final touch, stuff each mud ring with a wad of brown paper. Drywall, and more specifically tape and bed is a messy process and will easily leave your precious wires coated with a glop of dried wall mud. For some of the main media locations, all the wire will not fit, so bag it to keep it free of mud.
- Everyone has their own style, but I like to drill multiple offset holes in the top plate (the 2X4 or double 2X4 running horizontally on the top of the studs in a wall) above the media cabinet and pull each “room” through a different hole. I can then label the rooms on the front of the stud so I don’t have to do the wire labeling after each room’s pull. If you color coded your cables, you have it made. This trick also allows you to get the media cabinet in, punch down all the wires, and then put on the permanent labels right next to the punch or connector – much more convenient than 2’ up the wire where you have to dig through a big bundle to find the right wire.
- Note that if there are too many wires to do this, or if the area is load bearing, you need to skip the top plate in this area and expect to leave a drywall “hole” for the “large bundle of wires” to be brought down. In this case, it is usually convenient to bundle wires by rooms with a label and then separate them by function just under that – again so the final label can be placed right next to the connector or punch for convenience.
- BEFORE drywall, go through and video every square inch of every room. Electrical, plumbing, conduit, low voltage, stud locations – everything.
- Do the low voltage pre-wire AFTER electrical and BEFORE insulation. That puts you in complete control of keeping low voltage wires away from electrical lines. I’ve had plenty of cases where electricians really liked the holes I drilled and put their wires in the SAME holes as my speaker and A/V lines – disaster if I hadn’t caught it.
Appendix A: Links to sources, references, and products:
Other good how-to and pre-wire guides:
Products referenced in this guide:
With 20 years in the Consumer Electronics space, David pioneered wireless LAN for home use in partnership with Linksys, rotating storage for portable electronics at Cornice, and is most recently a founder and chief marketing officer of BOCS Inc, the manufacturer of a new whole home A/V distribution system for retrofit applications