By Bob Catanzarite
swhowto.com

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Chapter 1

Planning 
Chapter 2


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Buying Tools
Chapter 2

The Rough-In
Chapter 1

The Rough-In
Chapter 2

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Chapter 1

The Central Wiring Panel
Chapter2

Finishing

Coax Stripping

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Compensate for
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CATx Stripping
and Terminating
Chapter 1

CATx Stripping
and Terminating
Chapter 2

Home Network
Wiring and Setup
Chapter 1

Home Network
Wiring and Setup
Chapter 2

Home Network
Wiring and Setup
Chapter 3

Home Network
Wiring and Setup
Chapter 4

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VOIP (Voice Over Internet Protocol)

Wireless
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Chapter 1

Wireless
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Chapter 2

Pull Cords

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  2001
Bob Catanzarite

 

 

 

 

 

The Rough-In - Chapter 2

 

Now that you have all of your outlet boxes mounted you need to drill the holes in the wooden framing for the cable bundles to be pulled through.

I should mention here that by far the best way to run your cables to the outlet boxes is having all of your cables grouped together as a bundle. That means that all of the cables are pulled at the same time through the same holes. 

How big to make the holes you will be drilling is a good question to ask yourself at this point. Most homes use 2x4 wood for the framing lumber. You don't want to drill a hole so large that the hole weakens the structural integrity of the 2x4 framing. And then again you don't want your hole so small that you'll have difficulty pulling the cable bundles through those holes.  At this point you should already know how many of which types of cabling you will be running to each outlet box. Of course the hole size you need to drill will depend on the overall diameter of the cable bundle you will be pulling. So, you need to know the overall diameter of your cable bundle. The best way I can see of determining the bundle diameter is to take short sample pieces of the ACTUAL cables that you will be using and put them together into a bundle and measure the overall diameter of your cable bundle.  

Running cable bundles through floor joists can be a bit more tricky and time consuming. Because these floor joists are supporting the floor above you can't drill holes in them that are so large that they affect their structural integrity. And Engineered or laminated floor joists can pose special restrictions.  You can refer to Mark Henrichs, www.wildtracks.cihost.com/homewire/ for more on this.  As Mark suggests you should consult someone in the know (like your home builder) when it comes to these Engineered or laminated floor joists.

This assumes that at this point you have already selected and purchased YOUR cabling and have them on hand to make a sample bundle that you can measure. If your planning is running a bit behind schedule and you don't have YOUR actual cabling on hand at this point then you'll have to estimate your cable bundle diameter. The table below shows some of the individual cable diameter for the cable types that you are likely to be using to help you estimate your overall cable bundle diameter.

Cable Type Cable Diameter
CAT5 0.237"
RG6 Quad Shielded 0.298"

Now that you know your overall cable bundle diameter you can decide on a hole diameter that you need to drill. Keep in mind here that when you measured or estimated your cable bundle diameter all of your cables were being held neatly beside each other making a nice tightly grouped bundle. What is going to happen when you get around to actually pulling these cable bundles is that the individual cables will twist and shift position as they are being pulled which will make the effective overall diameter somewhat larger. Knowing exactly what 'somewhat larger' means is difficult to say.  In addition, having the pull cord (if you are going to be using pull cords) wrapped and taped around the cable bundle will again make the effective overall diameter somewhat larger. See the photos below.

        
(Click for a larger image)

I think you can see here that this idea of estimating effective overall cable bundle diameter involves a lot of assumptions. You will be a lot better of to have already done your planning and have selected and purchased your cabling so that you can measure instead of estimate!

In my case, with a cable bundle consisting of three CAT5 and two RG6U Quad Shielded cables, and the pull cord wrapped and taped, the effective overall cable bundle diameter measured just under 7/8" diameter. This was measured from the sample in the photo above on the right. Knowing this I decided to use drill size of 1 1/8". This meant that the hole I'd be pulling through would be 1/4" larger that the effective overall cable bundle diameter. This choice of drill size meant that I would not be significantly degrading the structural integrity in the 2x4 framing lumber and. at the same time,  was not trying to pull cable through a hole that was to small.

So now you have your outlet boxes mounted and you know the hole size you'll be drilling. What type of drill bit to use? The best type of drill bit to use is an auger bit. An auger bit will drill a hole that has a relatively clean and smooth inside surface with fewer burs and splinters around the outside edges of the hole. This kind of hole will make it easier to pull cable bundles through. Auger bits get to be rather expensive in the larger diameters that you will be using. A cheaper alternative to an auger bit is a blade or spade bit. A spade bit leaves a much rougher hole and is harder to control as your drilling.  I chose to use a spade bit for my installation to avoid the cost of a auger bit. I would have been better off to have paid the extra for the auger bit . But the spade bits I used did get the job done. See the photos below showing the these two types of drill bits. The auger bit is on the left an the spade bit is on the right.

   

Don't assume that you'll be able to drill your holes with a cordless drill. These large diameter drill bits take a lot of torque to get them through the framing lumber. In some areas you will be drilling through two or more 2x4's sandwiched together. You'll need a relatively powerful drill that runs on AC power and has at least a 3/8" chuck. At this point most homes will not have electricity readily available inside the home but will have a AC power outlet available somewhere on the the lot. You'll need heavy duty extension cords long enough to get that AC power from the builders outlet box to the places you'll be drilling holes. Make sure you have AC power available, have enough extension cords and have a big enough drill. And ladders of course are a necessity.

If you will be drilling through floor joists and running cables  then you'll need to consider a right angle drill. See to photo below. These can be rather expensive and renting them would be an attractive alternative. Now, you don't absolutely NEED a right angle drill to work in the floor joists. You can get by using a straight drill but all of your holes will have be drilled at a slight angle which will make it more difficult to pull thick cable bundles through.  You'll also need to use shorter drill bits when your working in floor joists.

Now, depending on how you decide to do things, you need to either pull your cable bundles or install your pull cords. If you choose to install pull cords like I did you can refer to the Pull Cord section for some more detailed help on that subject. If you are choosing to pull your cables during the rough-in then read on.

When it comes to pulling your cables as a bundle of several cables together an indispensable device to have is a Cable Reel.  Several manufacturers make Cable Reels that you can buy and some of them go by some name other than a Cable Reel. See the Links Page for some of these manufacturers.  Shown below are just two of the many different styles you can buy.

  

I chose to make my own Cable Reel. My CAT5 cable came in boxes instead of reels which seems to be the norm. Because I needed two of these 1000' CAT5 boxes and my RG6 cable came on 1000' wooden spools I was able to rig up my own form of a Cable Reel using these with the addition of a simple broom stick. Click on the drawing below to see a larger view of this makeshift Cable Reel.

    ReelStand_2.JPG (26220 bytes)
(Click for a larger image)

This worked great for me for just the price of a broomstick. I did have to transfer some of the CAT5 cable that I bought in the cable boxes to a spare wooden reel that I scrounged up so that I had three places for CAT5 cable to come from. The key thing here is that you need a Cable Reel that will dispense enough of all the cable types that you will be pulling. In my case I was pulling three CAT5's and two RG6U Quad Shield cables. So my Cable Reel had to dispense these three CAT5's and two RG6U Quad Shield cables. The one drawback to this makeshift Cable Reel was that it was rather awkward to move around from one place to another.

When your pulling your cable bundles through an attic space you need to think about how to support them. I personally believe it is fine to lay the bundles across the 2x4 that make up the ceiling rafters. I mention this because some of the information you may see in the links I have provided in the Links section will say not to do this. The reasoning I think they are using for saying this is that the pressure from the  edges of these 2x4's can disturb the twist pattern that CAT5 cabling use internally. They are right to some extent about the 2x4's disturbing the twists. The twists are key to the ability of CAT5 handle the high speed of 100Mbit/second Fast Ethernet or Gigabit Ethernet. But I believe that the disruption to these twists will be minimal. This type of concern might be a good justification for using CAT5e or enhanced CAT5 cable. CAT5e exceeds the requirements for fast ethernet and having this extra performance headroom should make the cable more forgiving of this type of minor disruption in the twist patterns. The alternative to laying the cable bundles across the 2x4 ceiling rafters would be to build trays to support the cables. These trays would be very difficult, expensive and time consuming to build. Because I installed pull cords during the rough-in and then actually pulled my cables after the home was finished, I laid my cabling across the blown in insulation that was covering the ceiling rafters in my attic. The soft insulation did not disturb the twist pattern of the CAT5 cable I used. I personal would not hesitate to, and actually did,  lay the cable directly across the 2x4 ceiling rafters even without the insulation to act as a cushion. Just keep in mind here that you need to try your best to support the cable is a manner that will minimize pressure on the CAT5 cable. In addition, both CAT5 and coax cables have minimum bend radiuses and maximum pulling forces that should be observed. See this link in the Reference section. Be gentle with with your cabling.

I mentioned earlier that I think that binding your cable bundles tightly together is a bad idea. I don't like and didn't use any nylon cable clamps or metallic staples or any type of staples for that matter. These can compress and distort the all important twist pattern in CATx cables. Compressing and distorting coax cable can be just as bad as this will disturb the physical relationship between the center conductor and the shields. But the big reason I have for not binding the cables is the difficulty you'll have IF for some reason later on you need to replace one of the cables. What I did use worked great for me. I found these pipe cleaner like things in a arts and crafts store. I believe that they are sold there for use in making floral arrangements. They were cheap and came in 12" lengths. I just lightly wrapped these pipe cleaners around the cable bundles and lightly twisted the ends of the pipe cleaner together.  See the photo below.  This did a great job of loosely binding the cable bundles to make them neater and easier to work with and if a cable has to be replaced later on the pipe cleaners will just pop open when you pull on the cable. 

So, now you have your outlet boxes installed, and either installed pull cords or actually run your cabling.  Now comes the CWP. You can either install the CWP during rough-in or do it later in the finishing step you'll be doing when the home building has been completed and you have moved in.  I chose to install the CWP during the finishing phase after I moved into my home. I did it this way because I was building my CWP entirely from pieces as opposed to buying a prefabricated and expensive CWP. Building the CWP myself from pieces was relatively  time consuming but saved a lot of money over a prefabricated CWP.  There was not enough time being allowed for me to build and install the CWP during the rough-in phase.  I have a section dedicated the the CWP that you can refer to.

 

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