How To Vent A Gas Water Heater Through The Roof – The Easiest Way

How To Vent A Gas Water Heater Through The Roof

Hot water is an essential part of everyday life. Many people can’t live without a water heater. Whenever we are installing a gas water heater, building codes require that there should be a ventilator out of the room, through the attic, and out through the roof.

To do this, two critical measurements must take one on the ceiling above the water heater and one that is the distance from the attic floor to the roof. Once these measurements recorded, we are ready to begin.

Be sure there is nothing in the attic to prevent cutting a hole for the vent. You will also need to check the requirements of the water heater to determine the size of the vent pipe required.

Steps For Gas Water Heater Installation And It’s Vent Pipe

1. Mark the ceiling above the water heater to receive the pipe. Use a plumb bob to be sure the center of the tube at the ceiling and the center or the boot on the water heater are lined up.

2. Cut the hole with the jigsaw. In the attic, use the plumb bob to mark the center of the hole to be cut for the roof vent boot.

3. Drill a starter hole with the electric drill. Insert the blade of the jigsaw through the hole and cut the hole. Be careful not to oversize the hole, as this will cause a potential leak in the roof.

4. Install the pipe, securing each joint as needed. On the roof, slip the roof vent boot over the protruding pipe to be sure of the fit.

5. Install the roof vent boot so that water will flow over it where it meets the roof. This will require slipping the flange under the roofing shingles.

☠️ Warnings

Do not reduce the size of the pipe, as this can cause inadequate ventilation, resulting in carbon dioxide poisoning.


Always wear safety glasses.

Keep a tube of roofing caulk handy in case the area around the roof vent boot needs to reseal.

Gas Hot Water Heater Venting Requirements

There are plenty of requirements you need to take care of while venting the gas hot water heater, let us have a look at those requirements in the list below:

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  • You should be having proper piping facilities available, that will be the connection between your gas hot water heater and outer venting section.
  • For better placements make sure you have enough screws that will help you in fixing those pipes at the right place.
  • Along with other products you just also have some seal locks that are going to be placed on the starting of the outer gas pipeline and on the top.

This is the three most common Requirements to vent a heater. And make sure you have the ventilation kit before venting this. As your guide, we prefer two ventilation kit that is best for every heater. If you have this at your home already so you can’t buy it. But if you don’t have so you can buy it. So check them out below.

1. Mr. Heater F102848 4 Inch Vertical Vent Kit:

How To Vent A Gas Water Heater Through A Wall

Here we have vertical installation parts for all the MHU80 and HSU80 model unit heaters manufactured by Mr. Heater company. Within the package you would be able to get an adjustable roof flashing, an adapter based on your heater size, a 90-degree elbow, storm collar, vent cap, and wall fire stop.

All these products are made up of high-quality material that is going to provide you a long-term usage. Moreover, the products are placed in such a way that you would be able to use them without the help of an instruction guide.

2. Rheem RTG20184 3-5" Vertical Vent Kit:

tankless water heater venting through roof

The next option in the list of Rheem RTG20184 3-5inch termination kit within which you would be able to get an appliance adapter with an integrated condensation collector, condensate drain tube, storm collar along with Rain cap.

One of the major benefits of this vertical vent termination kit is that it is made up of high-quality material and is lightweight.

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Tankless Water Heater Venting Through Roof

Selecting the Best tankless water heater for yourself is a challenging task but along with that the next important step you need to take proper care of is how to vent a tankless water heater through the roof.

In case if you are also trying to find the answer for the same, then do follow the steps listed-below. As here we are going to have a look at thorough steps for doing so:

How To Vent Gas Water Heater In Basement

1. You would be able to take advantage of horizontal venting or up through the roof. Here we will be figuring out the steps to venting tankless water heaters through the roof.

2. Make sure you have PVC and stainless steel pipings with the help of which you can attach the water heater with the roof or above it.

3. While venting you should follow all the guidelines provided by the manufacturer. You need to take proper care that proper gases are being expelled from the heater, hence to do so keep a lot of space free around the heater.

4. At last you need to attach the venting piece, with the help of which you can carry forward whole gases out in the atmosphere. This step is really important, as it will ensure a better life of your tankless water heater.

How To Vent A Gas Water Heater Through A Wall?

All-natural gas water heaters must be vented to the outdoors to remove the byproducts of combustion produced from using the heater. The vents should go directly through an outside wall and can also bring in combustion air to the gas burner.

Most of these units require zero or minimum amount of clearance at the sides and rear, which allows them to install in a smaller area. And for better results, one can install a water heater roof vent. As when the gas water heater vent pipe installation is going on gas water heater venting options is good and safe.

A water heater vent pipe can be used for this venting with a hot water heater vent cap for safety reasons. Make sure that the ventilation direct outside the house, or else there is a chance of fire or explosion in the house.

water heater power venting Guide

How To Vent Gas Water Heater In Basement?

There are different ways to do it. If you are unfamiliar with the process. This can help you. The question is how to vent the gas water heater in the basement? The answer to this question is a power vented gas water heater, or one can direct vent water heater.

Also, one can buy a water heater power vent kit Online to make sure that the water heating vents quickly in the basement or anywhere you want.

Water heater exhaust vent, so make sure you don’t overuse the product, or the boiler may lead to the explosion as well. Water heater installation code requirements are a vent kit, drill machine, and a professional. If you are not sure about how to work with the drill machine.

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Water Heater Atmospheric Venting

A Comprehensive Guide On Water Heater Venting Basics!

All water heaters, whether they run on natural gas or liquid propane, they all require the system of venting. Burning gas is known as the process of combustion. It helps in the creation of heat and exhaust moisture and gases.

The ventilation system in the water heater helps in removing the byproducts from home and works as a safety measure for living beings. There are a few ventilation systems found in specific water heaters.

The Basics Of Water Heater Venting:

All ventilation systems use usually piping or ducting, which is known as flue, or chimney. It helps to bring the exhaustion of gases from the heater to throw it out from home. The ducting system is available in metal or plastic forms.

It depends upon the water heater to decide which one is suitable. The ducts are directly open to outwards, which remove the gas directly outwards. In some cases, larger appliances are needed, which improves the water heater venting system.

Installation Of The Venting System

While installing the water heater at home, make sure the installation of venting is done accurately. If there is a lack of the installation of a water heater venting system, it can cause a problem for the residents.

So take care of the water heater venting system, as it is necessary for the safety of the residents.

Proper Venting Prevents Backdrafting

Backdrafting is such a problem, which does not come in notice easier. Backdrafting is a common problem with water heaters. Backdrafting leads to stop the gases exit from the home. The gases end up in a house, and it can cause a problem for the living beings.

If you think, it happens due to the bad installation that is not the truth. The back drafting problem does not occur because of the venting design or fitting. The issue arises because of ventilation fans.

The fans help to let the gas out from the house and create vacuum effects. It helps to exhaust the gas from the water heater.

There are some water heaters, which includes fan assistance with the ventilation system, or some have a direct ventilation system. It won’t let anything wrong happen with residents.

How To Prevent Back Drafting?

Installation requires to be done perfectly. The water heater needs to be proper venting prevents back drafting. It avoids the leakage of gas from the heaters.

It is a very common tip, which one must consider. When the heater is on, never pack your home tightly. Open the windows, so that gas can be removed from the house easily.

Use exhaust fans in the house to prevent back-drafting.

So consider these points, and prevent your home and residents from back-drafting to keep them safe.

Gas Water Heater Venting Options

1. Atmospheric Venting

Most of the people do not know about the working of the water heater. They are only aware of the fact that the water heater warms the water, nothing else. But, one should be aware of the venting system of the water heater.

The reason being is, if the ventilation process is not good, then it can create a problem for the living beings in the house. Atmospheric vent water heaters are good in demand. But, one should know about the atmospheric venting system.

water heater vent cap

The atmospheric water heaters are the oldest type of water heaters. In the case of the atmospheric venting system, fuel gets heated, which heats the water. In the atmospheric venting system, the pipes are set up to remove the gas from the home.

The combustion process generates the excess of gas, which goes out of the chimney. The best thing about atmospheric venting is that there are no requirements for electricity required.

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If the power goes out, still you can heat the water. An atmospheric venting system is less expensive in comparison to other venting systems.

It is good to choose the option of atmospheric venting. But make sure, while adapting for the option, keep an eye on the installation, because lack of installation can cause an issue for the residents.

2. Power Venting

A power venting system requires a fan or a blower to exhaust the gases. The pipelines are set up horizontally, and the fans exhaust the gases by pushing them outside through the pipes.

In these types of venting systems, there is no requirement of the Chimney. There are a few locations, which do not give access to the vent or chimney. In this case, there are limited options left for the consumer.

water heater roof vent

What Is In Power Venting?

You know what the best thing about power venting is. One can fit the heater anywhere in the house they want. There is no requirement of the vertical chimney to be installed. It is a great deal to choose the power venting water heater.

But on the other hand, making the selection of this one can be proven as an expensive deal also. When the blower runs, there is a slight notice generate because of the blower or fan, which can irritate the homeowners as well. But, the noise can be controlled, if you will ask while the installation for that.

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gas water heater vent pipe installation

3. Direct Vent Water Heaters

When it comes to direct vent water heaters, with the help of fuel combustion, the water gets heated. The direct vent water heaters are well in demand. Through the pipeline or chimney, the exhausted gases directly go out of the house.

The direct vent system works very simply. It is just that the hot air is lighter in comparison to cold air. When the warm air uplifts, it directly goes out from the house through the chimney.

The best thing about the direct venting is, it does not require more specific powers. Overall, the direct vent water heater cost less than other water heating venting systems.

For an accurate combustion process, the direct vent water heater requires fresh air. Basically, from outside, the combustion air comes in through the venting pipes.

It is made with keeping the safety measures of people in mind. It is a solution to the problem of back-drafting. Plus, in a power venting system, it creates noise. But, the direct vent system does not make noise at all.

The combustion process is sealed. No chimney is required with this venting system. The direct vent water heaters are easy to install. In the end, it is for sure that, if you buy a direct vent water heater, you will not regret it at all in the future.

gas water heater vent pipe installation


It is totally up to you, whether you want to consider power venting or other options. No doubt, it will result in a higher amount but is an effectual option to choose also. If there is no option of vertical chimney or vent, this will be a suitable option to pick.


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