How to Run Ethernet Cable Through Walls | Along Walls

When most people get confronted with the question of how to run ethernet cables through walls, they assume that cutting into walls is a big job only professionals can do.

Did you know you can do the job professionally for a fraction of the cost, and you get to keep the tools afterward? 

You just need to stick to a few simple rules and, of course, use proper materials and tools to achieve a polished and professional finish. So let’s get into the detail of how to run ethernet cable through walls and achieve a discrete and professional-looking finish.

Running Ethernet Cable Through Walls

There are three types of installation we are interested in here. 

1. Running ethernet cable from a Wi-Fi receiver in a room, up and through the attic, and down into another room
2. Running ethernet cable from one room into an adjoining room next door
3. Running ethernet cable through an external wall to the outside of your home, maybe to an outside office or workshop

The principle of running the cable and checking for obstacles is common to each installation. However, the starting point of each is different. So let’s start off with running ethernet through the interior wall from your attic to another room. 

How to Run Ethernet Cable Through Walls in 9 Steps

Fail to plan and you’re planning to fail…Like all home improvement tasks preparation is the key. 

First, you will need to decide on the path you intend to feed your ethernet cable and assess the required cable length. You can also take a look at any physical obstacles or barriers and see that you have the skills and equipment required to route the wire through. 

Here are the 9 steps to follow to run your ethernet cable through a wall, to achieve professional-looking results. 

1. Check for Existing Ethernet Installation

Most likely you already know whether or not there are any existing ethernet installations. Regardless, check around because if an existing connection exists, you may be able to get the connectivity you need by rearranging your space.

2. Identify the Path to Run Your Cable

Whenever I think about the path to run running a cable, I like to have the answer to some basic questions. For example, if I want to lay a cable from Point A to B, what’s the length? 

You can check this by running a piece of string roughly along the path, allowing you to double-check your cable length will reach the planned socket location. 

This will also allow you to visualize where you will need to drill holes in the wall. You can mark them with a pencil. We will come back to this shortly to check for studs, live wires, or water pipes. Each room will be cut off by a wall or ceiling so just use separate pieces of string and join them together at the end to get the total length of wire needed. 

Finally decide roughly where you want your ethernet cable connectors so you know where to fix your wall connector plates.

Running Cable to A Non-Adjoining Room

As you assess the cable path, you may well find yourself trying to run a cable up into the attic and back down into a none adjoining room.

It is important to realize that you will need to run the cable up or down through the stud wall top plate and through the attic space. External walls will be off-limits as they will be insulated and you won’t be able to access the top plate for drilling, as you won’t have the headroom for access due to the roof.

We can look at how to do this in more detail in step 6.

3. Materials and Tools Check-List

At this point, I recommend you stop and recheck your equipment, prior to making any sort of physical changes such as drilling holes or cutting drywall. 

Here is a list of equipment I used last time I did a cable run of this type. 

• Drywall Saw: Ideal for cutting out holes in your drywall to locate your wall plate
• Fish tape: Handy for pulling wire through wall cavities.
• Measuring tape: Measure twice…cut one…this old saying has served me well over the years. Never guess, just measure it up to be sure. 
• Stud and Metal Finder: Handy in locating wall studs, metal conduit, pipes, or even electrical current.
• Spirit Level: This will keep things level
• Power Drill: Ideally a cordless battery-operated drill for drilling holes in walls and studs
• Drill Bits: A range of bits and cutting drills and paddle bits to cut holes in walls and wood
• Pencil or Marker: For marking drill or cutting locations
• Crimping Tool: For attaching wire connectors
• Ethernet Wall Plate: This socket is where your ethernet cable plugs into the wall.

4. Check for Wall Studs, Water Pipes, and Live Wiring

Whether you running up, down, or simply through a wall cavity you will need to check for hazards or obstacles. 

Most people might wonder, how do I see inside the walls for pipes and wiring? If you don’t already know how to check, it’s a valid question. 

Locating Wall Studs

You will usually find a stud right next to an existing wall socket. You can push a narrow screwdriver through the wall to locate the stud. If you go to the wrong side of the socket first attempt, then the repair is small. Studs are usually located 16 inches apart in the USA and 24 inches apart in the UK. So find one and you can work within the cavity space next to it.

Alternatively use a stud detector. This simple electrical device can check the wall density and will give a beep when the density increase and a stud is located. 

Locating Wires and Pipes

For wiring and pipework, there are many ways to locate them. But for the general DIY installer, I would recommend you purchase a detection device.

In fact, you can purchase a detector for wall studs, metal, electrical current, and even pipework. 

For around $30 you can buy a 5-in-1 detector from Amazon.com and save yourself a potential drama.

Most homes have attics, and you can move insulation out of the way above a wall you want to drill through. More than likely, you will have floorboards under your insulation. You can remove floorboards and look underneath. You can also make a hole in the wall top plate and drill through it.

One method is to make two holes. Shine a flashlight down one and look through the other hole. Zooming in with a camera might work better. Once you pull up some insulation, there is a good chance you can eliminate plumbing or wiring as a concern because you can often see it from the attic and avoid that section of the wall.

5. Mark and Cut Your Ethernet Cable Wall Jack

The Ethernet cable wall plate can be used as a template for marking and cutting the hole in your drywall. 

1. Simply position it next to the wall, at the same height as your other wall sockets. 
2. Check it is level and mark the screw holes. 
3. Start by cutting a small hole and work your way out until the wall plate fits. It is important not to draw around the wall plate and cut it out, as this hole will be too big. 

Leave some wiggle room in your gap so that you can easily pull the cable through without a struggle.

If you are cutting a hole for an ethernet jack, you only need to cut a hole big enough to hold the jack plate. Remember to make a small hole and get progressively bigger until the jack fits into the hole.

6. Drill a Hole in Wall or Stud Top Plate

So you have your wall plate located and cut out. Let’s look at two possible options, running the cable to an adjoining room on the other side of the wall, or to a non-adjoining room in another part of your home.

Running Cable to Adjoining Room 

If you are running cable straight through a wall simply repeat this process in the wall of the adjoining room by drilling through to that room via your wall plate entry point. 

Then repeat the cutout process for the second wall plate.

Running Cable to a Non-Adjoining Room

To run a cable up through a cavity wall, across your attic space, and down into another area of your home is a bit more involved. But let’s start with your wall plate where you will run the cable from.

Follow the wall up to the ceiling directly above your ethernet wall plate. Drill through the ceiling (not the wall) close to the wall. This will give you a hole to feed through a length of marker cable. The only purpose of this piece of cable is to give you a visual mark from the attic space of where your ethernet sock is located along the stud wall in the room below.

1. You can then go into your attic and locate this length of marker cable. 
2. Remove any insulation so that you can see the stud wall top plate located next to your marker cable.
3. Use a paddle drill or saw drill to drill vertically down into the stud wall top plate. This will drill down into the wall cavity. 
4. Use this drill hole to feed one end of your ethernet cable. 
5. Feed your ethernet cable down through the wall cavity until it reaches the floor or at least down to your wall plate hole.

Here’s a short 5-minute video produced by HomeDepot that uses some of the techniques I have described. It’s very clear and well made, so check it out as I think it will be very helpful in understanding the process. 

7. Run Your Cable Through Hole Into Wall Cavity

The fish tape is the best tool for running cable into the wall cavity. If your cable comes inside from outside, use materials with weatherproofing. 

Prevent water damage and reduce entrances for pests by sealing the hole with silicone caulk. Ensure that your cable doesn’t run near existing electrical lines, plumbing, or an electrical conduit.

8. Locate the Cable End

You can locate the end alone with fish tape. The job is easier for two people if one person pushes the cable while the other spots the end. Once you get the guide through the hole, pull enough through so the line cannot fall back into the wall cavity.

9. Connect Ethernet Cable to New Wall Jack

To connect an ethernet cable to a wall jack, you should go through some specific steps. 

You will need your crimping tool and to follow specific steps to get the wires in the correct order. First, you have to unravel all the wires and make sure not to lose the punch-down tool that comes with the jack.

You will need to check the manufacturer’s instructions on how to connect your specific cable type. The Cat 6 wire order is typical as per the diagram. Carefully ensure the punch-down tool pushes the wires into the jack to the ends of the slots. 

Whatever kind of jack you have, look for a diagram on the back that shows how the wires go.

To connect an ethernet cable to a wall jack, you should go through some specific steps. 

Trim off excess wires and add the wire cover. You can also buy a professional pushdown tool that pushes and cuts in one motion. When completed, you have assembled your jack, and all you have to do is feed the wire through the wall and attach all wall plates. 

For a new plate, use a level and make marks before drilling. Once you drill the screw holes, you want to get a level plate on the first attempt.

Running Ethernet Cable Outside Through Exterior Walls

Exterior walls follow most of the same rules as the interior walls previously shown. The primary extra considerations consist of weatherproofing, avoiding EMI exposure, and sealing holes properly to prevent water damage and keep pests out.

Ethernet cables have very low voltage, so there are no safety concerns. If you live in a place with housing rules or codes, you should find out if you can lay cable without running afoul of the rules.

Use Outdoor Ethernet Cable

Ethernet cables for outdoor use will be weatherproof. I recommend using a round cable. You don’t want to have to replace or maintain cable outside. 

As I mentioned before, 100 meters is the longest cable you can buy. The shorter you can make the cable, the better signal you enjoy. Exceeding 100 meters will lead to signal deterioration. Look for the solution that gives you the shortest cable length possible.

Mount an Outdoor Rated Box

Before mounting a box, make sure you need a box. There might already be an ethernet line running into the house that you can use or modify.

If you need a box, look for a spot that has some protection from the weather. Whether you can find a protected spot or not, buy a weatherproof box. The box protects the connection of the ethernet cable to the ISP hardline.

Many homes already have a weatherproof box installed somewhere. Ensure that you cannot use a previously installed box. If you have to buy one, pay the extra money for high quality. The connection point must not get wet or have sunlight degrade the materials.

Plan Your Ethernet Cable Run

Before you buy a weatherproof cable, plan and measure your run. Remember to purchase more than you need in case unforeseen obstacles arise.

More than likely, you will run the cable to the wall nearest to the ISP hardline. Avoid electrics and plumbing in the walls. I recommend scanning the walls inside the house because you can scan thin drywall easier if you have to go through drywall.

Most people try to run cable through basements, attics, or crawl spaces. You can see electrics and plumbing more easily than in drywall. From attics and basements, you can access any room you want.

Drill a Hole for Ethernet Cable

Just like before, you want to have a long enough drill bit to get through the wall. Also, some locations on exterior walls require powerful drills with heavy-duty bits. The drilling location and building materials determine which tools you need for the job.

Most of the time, a half-inch drill bit that is 12in long will work. If you are drilling directly into a room, drill from the inside out. Drilling from the outside usually works best for going into attics, basements, and crawl spaces. You have more room to maneuver outside, and you don’t need to worry about precision hole placement.

Run the Cable to the Desired Location

If you drilled into a room, you are probably in your desired location or can follow the indoor steps above to get to your desired location and move on to installing a wall jack.

From attics and basements, you can usually get to the room you want from your hole. You can attach your cable to a rod or wire and poke the metal through the hole, go to the other side and easily pull the wire through along with the cable.

In the process, try not to bend or twist the cable to avoid doing damage. Avoid insulation when possible.

Use measurements to find the spot where you can drill and run the cable into an interior wall to attach a wall jack.

Install Your Wall Jack

Once you know where the wall is where you want to put a jack, install a jack with the methods discussed above in the interior section. Your best bet is to use an RJ45 jack. Again, look for a diagram that shows the order when arranging the wires.

A standard RJ45, starting on the closest connection on the left side, goes—orange, orange-white, green, and green-white. The closest connection on the right goes brown, brown-white, blue, and blue-white. A network cable tester will tell you if the order is wrong.

Check the Wall Jack and Box are Sealed

The box should have a weatherproof design. Carefully seal the box so the weatherproofing does not fail to work.

Find the hole on the outside wall where the cable enters the home. Use silicone caulk to seal the hole. The caulk resists shrinkage very well and prevents unwanted weather and bugs from getting inside.

Choosing the Right Network Cable

The first consideration when choosing an ethernet cable is to compare the capacity of the cable versus the speed of the internet connection coming into your home. You can get this information from your internet service provider. 

There are also many sites that offer free speed tests online, so you can check how your internet is performing. You’re looking for the number of Mega Bytes Per Second (Mbps). 

You then need to match your ethernet cable to be capable of handling your internet speed and file transfers. Remember, when installing any technology into your home, make sure it is future-proof so I would also go over the basic recommendation.

If you’re not sure about the right cable the entry-level is Cat 5e, then Cat 6, but I would suggest a good place to start is to look for a Cat 6a cable. Cat 7, or Cat 8 cables are for office use or extreme capacity. Selecting the right ethernet cable is a blog post in itself, so if you need more advice on this there’s a great article on choosing an ethernet cable. 

Flat vs. Round Ethernet Cable

Round and flat cables have their functional advantages. For me, the primary difference comes down to durability and reliability. Round tables are more durable than flat cables, as they can flex in any direction. Flat cables tend to flex up and down due to the cable profile, but not side to side. 

Flat cables are perfect for low-profile use when running a cable along a wall, rail, baseboard, or underneath a carpet. They also have a broad flat profile which is great for adhesive contact when sticking them down to a surface. 

That being said Round cables are the go-to profile for running ethernet through walls. They are flexible in all directions which is ideal when bending through cavity walls. They also offer a better level of rigidity when feeding through wall cavities or drill holes. 

How Far Can You Run Ethernet Cable from a Router?

There are limitations to what can be achieved with extreme lengths of data cable. The table below illustrates the Max Data Rate you can achieve with various lengths of cable. Considering most people will want to run a length of cable no more than 50 feet sticking with a Cat 6a cable or above would be ideal for home use. 

Cable Category	Max. Bandwidth	Max. Data Rate	Shielding
Cat 5e	100MHz	1Gbps (>328 feet)	No
Cat 6	250MHz	10Gbps (>180 feet)	Shielded/unshielded
Cat 6a	500MHz	10Gbps (>180 feet)	Shielded/unshielded
Cat 7	600MHz	100Gbps (>49 feet)	Yes
Cat 7a	1GHz	100Gbps (>49 feet)	Yes
Cat 8	2GHz	40Gbps (>98 feet)	Yes

Verdict: How to Run Ethernet Cable Through Walls

Wiring a wall jack might be the most daunting part for inexperienced people who take on the task of installing an ethernet cable and/or jack.

Most of the process indoors should not prove too challenging for homeowners who don’t have wiring experience. Going through outdoor walls might overwhelm some people, but once the cable is inside, the task is manageable again.

If you face your fears of wiring a jack and fail, you can still call in a professional to get the job done, and the right materials are already in the home.

Installing Ethernet Cable FAQs

Here are the most common FAQs related to installing ethernet cables through a home’s walls.