How To Vent A Gas Water Heater In The Basement [Step By Step Guide]

Gas water heaters can be a significant source of odor, mold, and potential gas leaks if they aren't properly vented. Fortunately, venting a gas water heater in a basement can be a straightforward process with the proper planning and equipment. We have researched this process thoroughly, and here is what we have found.

A gas water heater usually requires special venting procedures. Here is a brief overview of how to vent a gas water heater in a basement:

  1. Prepare a hole in the basement wall
  2. Connect the draft hood
  3. Attach the draft hood to the vent pipe
  4. Connect the vent elbow to the vent pipe
  5. Insert the storm collar into the vent elbow
  6. Install the vent cap to the outdoor area
  7. Apply a sufficient amount of sealant

Venting a gas water heater in a basement might become challenging if you don't have all of the necessary information. Continue reading as we add more details to these steps, as well as significant information on how to prevent mishaps and costly mistakes.

How Does A Gas Water Heater Work?

A gas water heater heats water in a tank through the combustion of gas in a burner located at the bottom of the tank. The hot water rises to the top, where a discharge tube pulls it out.

Goodman high efficiency furnace with bradford white residential gas water heater

A heat exchanger in the heater warms cold air drawn in from the ducting of the house. The exhaust from the furnace is blown outside the house through a vent, and the heated air is distributed throughout the house via ducts.

Gas water heaters can be installed outdoors, above ground, or in the basement and have a buried gas line that runs underground.

The gas line can be installed in a crawl space or indoors via an exterior wall. In some homes, the gas line can be run under the basement floor.

Most gas water heaters have the potential to be installed indoors, and there are certain circumstances in which an indoor installation may be recommended.

How To Vent A Gas Water Heater In A Basement?


The following are the materials and tools you'll need to vent a gas water heater in a basement:

  • Gas water heater kit
  • Drill
  • Vent pipe
  • Draft hood
  • Vent elbow
  • Storm collar
  • Vent cap
  • Screwdriver
  • Screws
  • Sealant

You can vent a gas water heater in your basement successfully by following these steps:

Step 1: Prepare A Hole In The Basement Wall

First, drill a hole in the basement wall or ceiling where the vent pipe will pass. You need a minimum of one-inch clearance from the line to the hole area.

The vent pipe should not touch the material of the wall. This is for fire safety, since the pipes can be heated to high temperatures that can cause the material to combust if it is flammable.

The hole should be large enough for vent covers and storm collars to fit and cover.

Check out this storm collar on Amazon.

Step 2: Connect The Draft Hood

Gas water heater draft hood

Install the draft hood. Place it over the top of your gas water heater in the area directly above the water heater vent.

The draft hood is usually supported by three or four short legs. Depending on the type of water heater you have, these may be screwed to the top plate. They may also have pin- or hook-shaped ends that fit into holes on the top of the heater. 

Center the draft hood above the vent hole of your heater. The legs of the draft hood should be straight for the venting system to function properly.

You should repair or replace the draft hood if it is not properly aligned to the vent or if its legs are bent or broken.

The size of the vent pipe should match the size of the draft hood as much as possible. This is an important consideration that can prevent backdraft from occurring in your venting system.

A vent pipe that is a bit larger than the draft hood is fine, but the opposite is not advised to prevent backdraft of flue gases.

Step 3: Attach The Draft Hood To The Vent Pipe

Attach the draft hood to the pipes for your vent. Sheet metal screws should be used to ensure strong connection between the two materials.

Do not seal or fasten ties with conventional duct tape. Aluminum tape is prohibited from being used on joints by some construction inspectors, since it can hide problems like corrosion or pin holes.

When connecting to a double wall or B-vent pipe, use screws only for the initial connection. B-vent pipes use different locking mechanisms depending on their size.

Smaller ones can be safely connected using twist lock fittings, while screws are necessary for larger pipes.

Step 4: Connect The Vent Elbow To The Vent Pipe

Next, connect the vent elbow to the vent pipe. The vent pipe has a unique snap ring that allows the vent pipe to go together when rotated.

The vent elbow has a 90-degree articulated point that enables it to be adjusted and bent.

Check out this vent elbow on Amazon.

Step 5: Insert The Storm Collar Into The Vent Elbow

Twist the storm collar into the vent elbow so that it is locked in place and install it through the wall.

The storm collar helps to keep rainwater from entering your home. It is also used ">inside through a subfloor or a wall penetration for insulation purposes, to cut down on air drafts.

Step 6: Install The Vent Cap In The Outdoor Area

After that, install the termination vent cap in the outdoor area. Go outside and install the remaining parts of the vent. Check that everything is connected correctly.

Step 7: Apply A Sufficient Amount Of Sealant

Apply sealant where it is needed. This includes the areas around the screw holes and the edge of the vent pipe.

Watch the video below to learn more on how you can install a venting system for your gas water heater. The video shows how to install a venting system in your garage, but the steps are the same if the heater is in your basement.

What Happens If A Gas Water Heater Is Not Vented Properly?

Man feeling dizzy and trying to balance against a wall

Carbon monoxide is a common byproduct of water heating or combustion. If you're not careful and your gas water heater is not vented correctly, this can cause carbon monoxide leakage in your house.

Carbon monoxide can cause dizziness, fatigue, nausea, chest pain, and irregular breathing. Prolonged exposure to high levels of carbon monoxide can result in gas poisoning and even death.

To keep things safe, you should follow the correct procedures when venting your gas water heater.

What Are The Different Venting Systems For A Gas Water Heater?

Here are the three types of venting systems for a gas water heater:

Atmospheric Venting

Atmospheric venting uses the force of air to vent the flue gases out of your heating system. This method uses a vertical pipe that is may be linked to your home's chimney.

The heated flue gases rise through the vertical pipeline and out into the atmosphere. The longer the vertical pipeline used, the higher the system's efficiency in venting out the flue gases.

This venting system is the cheapest among the three methods because of the low cost of installation and the fact that it doesn't need electricity to operate.

Direct Venting

Direct vent systems have sealed combustion chambers. Horizontal flue pipes that go out of the external wall are usually used to vent the flue gases outside.

The sealed chamber design offer more options with installation compared to atmospheric venting. It is also safer to use if flammable or corrosive products are nearby.

Power Venting

Power vent systems move flue gas outside by the use of mechanical fans. Using mechanical fans allows the water heater to be far away from the outlet of the flue gases.

Both horizontal and vertical pipes are used to transport the flue gases from the heater system to the outside atmosphere.

This venting system is recommended for closed homes with poor ventilation and no chimneys. The disadvantages of power venting include its dependence on electricity and the noise produced by the mechanical fans.

Advantages of Gas Hot Water Heaters

Female hand puts thermostat of electric water heater

Gas water heaters are a popular choice for homeowners because they can heat a tank of water relatively quickly and have lower operating costs than electric heaters, making them a convenient option for larger families.

A gas water heater has important safety features, like a pilot light that stays lit until the water is turned off, a hot water shutoff valve, and a gas valve that shuts off when the water is shut off.

Gas water heaters require little to no maintenance, unlike electric hot water heaters, which can become clogged with dust and minerals.

Another significant advantage of gas water heaters is that they will still operate in case of a power failure or outage.


Gas water heater in the basement

You should vent your gas water heater in the basement to ensure the safety of your water heater. The process might seem complicated, but it can be a manageable task if you have the knowledge and suitable materials and tools.

If you found this post helpful, check out our other related articles:

Gas Heater Not Working But Pilot Light On – What Could Be Wrong?

How To Clean The Flame Sensor On A Rheem Tankless Water Heater [Step By Step Guide]

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One comment

  1. For water heaters with inadequate ventilation, direct vent systems are the best option. Two distinct pipes connect to these vents: one draws in outside air to promote effective combustion in the water heaters, while the other pushes exhaust gases outside the house.

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