You should never run an ethernet cable through the vents in your home. The heated air in your vents can damage the wires, which will interrupt your internet service and release toxic fumes from the cable’s plastic casing. An ethernet cable inside a vent poses a fire risk. Not only do you risk destroying your home, but most insurance companies will not award insurance payments if the cause of the fire was due to an ethernet cable installed inside a vent. Similarly, running ethernet cable through vents is against most building codes and can be a violation of a lease. If you run an ethernet cable through your vent, you may risk eviction.
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Is it Safe to Run Ethernet Cable Through Vents?
It is not considered safe to run an ethernet cable inside or alongside the vents in your home. Professional installers will not run ethernet cable through vents because of the risk of damage to the cable as well as the risk of fire and other home damage. Both electrical wires and ethernet wires should never be run through vents.
Can You Run Ethernet Cable Through an Attic?
It is safe and recommended to run ethernet cable through your attic space. You can follow our steps for running ethernet through your attic to get the job done right. By running your cable through your attic you keep the cable safe from heat damage and can safely run a cable to upstairs rooms. It’s a far better solution than snaking a cable through your vents.
Can You Run an Ethernet Cable Through the Wall?
Running an ethernet cable through a wall is one of the best installation methods. Our step-by-step guide to running ethernet cable through exterior walls is a good starting point. It covers the basics of a safe, durable application. It also covers choosing the right ethernet cable in order to receive the best internet service.
7 Reasons to Never Run Ethernet Cable Through Air Ducts
There are several reasons not to run an ethernet cable through an air vent. We’ll cover them below. Keep in mind, Pepper’s Home & Garden is not operated by legal professionals and we are not offering legal advice. We are simply trying to keep you and your home safe with the correct ethernet installation tips.
Heat Damage
The plastic coating around ethernet cable is not designed to withstand high heat. Because the heated air in your vent can exceed 150℉ (65℃), it can damage the cable’s casing and the wires inside. This heat damage can destroy the cable, cutting off your internet service. This is the most common occurrence if cable is installed inside an air vent.
Sharp Edges
Air ducts are created by cutting and joining several pieces of metal duct. Both the interior and exterior of the air duct often have sharp metal edges. This can cut your ethernet cable or damage the casing. Any damage to the casing in turn makes it much easier for the cable to be destroyed by heat. Because the exterior of the duct has sharp edges, it’s also not advisable to run an ethernet cable directly alongside air ducts in your wall. Ethernet cable should be run separately from ducts.
Toxic Fumes
Heat damage to ethernet cable coating can release powerful, toxic fumes. These can be invisible or may manifest as black smoke. Either way, these fumes are harmful to you, your family, and your pets. Inhaling plastic fumes can cause damage to your airways and nervous system.
Fire Risk
The heat in your air vent can actually cause your ethernet cable to catch fire. The PVC coating on most ethernet cables has a low smoke point and can catch fire relatively easily. In order to prevent a house fire, do not run ethernet cables inside your ducts.
Voided Insurance Claims
In some cases, insurance companies will not pay for damages caused by running a network cable through your heating duct. This means that if your cable does catch fire and damage your home, you may be stuck paying for the repairs yourself. Although fire risk is most associated with PVC-jacketed cables, every ethernet cable type is a fire risk if installed inside a vent.
Violates Lease
Due to the fact that ethernet cables inside ducts carry a risk of property damage, if you perform this sort of installation in a rental, you may be subject to eviction. No matter what type of cable you use, your landlord may have grounds to terminate your lease if they find a cable in heating or return ducts.
Against Building Code
Your local building code determines what is and isn’t legal during home building and renovation. This includes electrical wiring and ethernet lines. Many building codes make it illegal to install an ethernet cable inside a vent or cold air return. In order to avoid violating building code, install your cable in a building-code-approved fashion.
Can You Run Ethernet Cable Through Air Ducts?
If you need internet service on the 2nd floor of your home, never install ethernet cable in an air duct, even if you believe it’s a cold air duct. The reasons to avoid this are:
- Heat in the duct can destroy the cable.
- Sharp edges inside the duct can also damage or destroy your cable.
- A cable exposed to heat inside a duct can release toxic fumes into your home.
- Cables inside air ducts are a cause of house fires.
- Your insurance company may not pay for fire damage if the cause is an ethernet cable in a duct.
- Your landlord may have grounds to evict you if you install ethernet cable in a duct.
- Installing ethernet cable in a duct is considered a building code violation in many places.
To be on the safe side, make sure all runs of ethernet cable in your home are not inside air ducts. Then, follow the correct process for installing an ethernet cable by running it through your attic or through a wall.
