One of the most important choices you’ll make when it comes to your new range hood is whether or not it will vent outside. Ducting your vent hood to the outside is the best option to keep your air clean and healthy.

But, depending on the design of your kitchen, you may be limited to where you can install the ductwork.

Before you install ductwork, be sure you have the room to run it from your range hood to the outside. If you have the space, you have a few different venting options.

Range Hood Venting Options

The ducting may run horizontally or vertically depending on your type of hood. Island hoods must vent through the ceiling, while wall hoods can vent through the wall or ceiling.

Installing Range Hood with Horizontal Duct

You have two options to vent your wall hood horizontally.

Installing Range Hood with Vertical Duct

You can also vent your wall hood through the ceiling, as in the diagram below.

Unlike wall hoods, island hoods can only vent through the ceiling.

You may be wondering: which venting option is the best?

The best ducting option for your range hood will depend on your kitchen design. But there are several things you can do to maximize the efficiency of your range hood duct.

Best Practices When Installing Range Hood Ductwork

1. Do not terminate the vent system into an attic, or another enclosed area. 

If you follow any tip in this list, follow this one. It is vital that you vent your hood outside your home, through the ceiling or wall.

It’s not healthy for smoke, cooking exhaust, humidity, and contaminants to build up in your attic. Instead, run the duct all the way to the outside. This way, you’ll get rid of the smoke and cooking exhaust for good.

The best option is to vent vertically through the roof if possible, since hot air rises. But this is not required. Vent through a side wall if you cannot vent directly above your hood.

To have a smooth installation, find a great contractor to install your ductwork.

2. Do not use more than two elbows in your ductwork. The fewer elbows, the better.

Each elbow adds some resistance to your duct system, which makes it harder for air to make it to the outside.

A couple of elbows are OK; you might need them just to navigate through your walls. But don’t use more than two to keep your hood running as efficiently as possible.

When adding elbows to your duct, keep the following in mind:

• For each elbow in your duct, reduce the total length of your duct run by 5’. For example, a 30’ straight run is about equivalent to a 20’ run with two elbows.
• When installing your duct, include at least 18″ of straight run before adding an elbow.
• Make sure there is at least 24″ of straight duct between each elbow.

3. Install your ductwork in the shortest unobstructed path to the outside of your home.

When possible, orient your ductwork so that you use the shortest run possible with the fewest elbows. This way, the unwanted air encounters the least amount of resistance and vents out of your home with ease.

Ignoring aesthetics, the shortest and straightest run of ductwork is the best for the power, efficiency, and longevity of your vent hood.

Do not use more than 30’ of ductwork. The longer your duct, the more resistance it has.

If your duct is longer than 30’, the air will really struggle to make it to the outside, even with a powerful range hood.

4. Use rigid galvanized steel or metal HVAC ducting only. Do not use plastic flexible duct.

A range hood should last you 10+ years, but flex duct simply won’t hold up that long. Rigid duct is much more durable. It’s your best option.

Rigid duct systems will also encounter less air resistance than flex duct systems, so all the greasy kitchen air will move smoothly to the outside.

Make sure that you use the appropriate sized duct to keep your duct system efficient. Duct size depends on the CFM of your range hood.

For example, if you have a 900 CFM hood, do not reduce the diameter of your duct below 8”. See the graphic below.

Once you’ve installed the appropriate duct, seal it to your hood using aluminum tape.

5. Seal the end of your duct run with a wall or roof cap.

A cap keeps dirt and debris out of your duct. It also prevents backdrafting, which is when outside air moves into your duct.

Then, use caulking to seal exterior openings around the cap.

This keeps the cap secure and prevents greasy kitchen air from leaking out the edges of your duct system.

What is a ducted range hood?

A ducted range hood moves air through a duct to the exterior of the home. A ducted hood can be installed through your cabinetry, ceiling, or straight through the wall behind the hood. Ducted range hoods are common in commercial kitchens, homes with gas stovetops, or higher-end homes. They are almost always the preferred choice for cooking ventilation.

That covers some of the most important things to consider when installing ducted range hoods. Now, we’ll discuss ductless hoods.

How do ductless range hoods work?

Ductless range hoods do not vent to the exterior of the home like ducted hoods. Since they cannot expel the air they take in, these range hoods filter the air and then recirculate it back into the kitchen. The air is then filtered through charcoal or activated carbon, which removes contaminants before it recirculates back into the kitchen.

The charcoal filters are located within the range hood on the blower. They cannot be cleaned, so they must be replaced after about 150 hours of cooking, depending on your cooking habits. If you cook intensely with a lot of grease and smoke, you may need to replace them more often.

Generally, the charcoal filters can be expensive, but here at Proline, our ductless models work effectively with inexpensive, premium quality, and easy-to-replace charcoal filters.

Which is better, a ducted or ductless range hood?

Ducted range hoods are almost always preferable over ductless range hoods, since they vent the kitchen air to the outside of your home. Ducted hoods are much more powerful and efficient than ductless hoods. They will keep your kitchen air clean and fresh for years to come.

Some homeowners who live in an apartment or can’t install ductwork in their home will use a ductless hood.

What is the difference between ducted and convertible range hoods?

The main difference between ducted and convertible range hoods is that convertible hoods can convert from ducted to ductless. Convertible hoods come with a recirculating kit or charcoal filters to convert the hood to ductless. A ducted hood, on the other hand, cannot be installed as ductless.

Ducted vs Ductless Range Hoods

While a ducted range hood is the first choice for most chefs and homeowners, both ducted and ductless hoods have their pros and cons.

For a more in-depth comparison of ducted vs ductless range hoods, check out this complete article.

Ducted Range Hood Pros

• Completely removes smoke and fumes from the kitchen

A ducted range hood pulls the smoke, grease, and unwanted contaminants through ductwork and outside your home, compared to a ductless hood which merely recirculates the air back into your kitchen.

• Keeps your walls, cabinets, and ceilings grease-free

With all the dirt and grime completely gone, your cabinets and the surrounding area will stay clean for much longer than they would with a ductless hood.

• Eliminates strong odors in the kitchen

Ducted hoods also remove strong odors from your kitchen, which is especially great if you cook Asian food or fried food.

• Does not include charcoal filters – no need to replace them!

Hoods that duct to the outside use stainless steel baffle filters or mesh filters which are dishwasher-safe. This is cost effective in the long run because you don’t have to consistently spend money on charcoal filters.

• Keeps excess heat from your cooking out of the home

While cooking, the heat generated from the burners or grill can warm up the kitchen fast. But a ducted range hood can send this hot air outside your home in no time. With a ducted hood, you can cook comfortably and have an enjoyable experience in the kitchen.

• Compatible with inline or external blowers which are much less noisy than local blowers

Inline blowers are no different than local blowers in terms of efficiency, but they are placed inside your ductwork –further away from your kitchen. This drastically reduces the noise level or sones of your vent hood.

Ducted Range Hood Cons

• Can’t be installed in every kitchen

You may not have the room for ductwork, which means you will either have to make room (this can be expensive and time intensive) or invest in a ductless hood.

• Ductwork is an added cost

Since you need a professional to install ductwork, you will have to factor its installation into your budget.

Ductless Range Hood Pros

• Can go almost anywhere

You have much more freedom in where you locate your ductless range hood. You are not bound by where ducting can go or already exists.

• Easy to change the layout of your kitchen

When remodeling, a ductless range hood can be reinstalled at another location. Plus if you’re renting, you can take it with you when you move out.

• Saves money

Since you don’t need to install ducting, you will save immense time and effort.

• Uses less energy

Ductless hoods don’t require the power to move air through ducting to the outdoors.

• Quiet

Although ductless hoods are not as powerful as ducted hoods, they are incredibly quiet. Believe it or not, the low CFM comes with an advantage – noise level – especially with an efficient blower or blowers.

Ductless Range Hood Cons

• Not as efficient as a ducted range hood

The number one disadvantage of a ductless range hood is that it is incapable of removing as many air contaminants as a range hood that vents outside. Unlike ducted hoods, ductless hoods don’t remove heat and moisture – they simply recirculate it back into your home. This means your kitchen may become quite humid while cooking – and smells may linger for a longer period of time.

• Charcoal filters are inefficient

Charcoal filters cannot filter out smoke and grease fully which could result in cooking odors and grease build up on kitchen surfaces.

• Charcoal filters require replacement

Charcoal filters need to be replaced every three to six months or after about 120 to 150 hours of cooking.

If you are contemplating installing a range hood that will vent outside, make sure you carefully consider the pros and cons. Even though ducted range hoods are preferred, they might not always be the right option.

Some homeowners may be fine with a ductless range hood if they live in an apartment, do not cook very often, enjoy low-intensity cooking, or prepare cuisine with fewer strong odors, such as vegetarian.

What type of duct is best for venting a range hood?

Rigid duct is without a doubt the best option for venting your range hood. Rigid duct is higher quality than flex duct and is made of much more durable materials.

For more information on choosing the right type of duct for your range hood, check out this article.

Do range hoods have to be vented outside?

No; range hoods without a duct, or ductless range hoods, can recirculate air back into your kitchen. However, to clean your kitchen air most efficiently, purchase a ducted range hood. Rather than relocate the cooking exhaust, it will evacuate it from your home entirely. This drastically improves your indoor air quality and is beneficial for your health and safety in the long-term.

How far can you vent a range hood?

Your range hood duct should not exceed 30’ for a straight run, 25’ for a run with one elbow, and 20’ for a run with two elbows. The shorter the duct, the better. If your ductwork is too long, your kitchen air may not reach the outside. Backdrafting can also occur, where air stays inside your duct, flows back through your hood, and into your cooking space.

How far should a range hood stick out?

A range hood should stick out at a minimum half the length of your kitchen range and typically does not extend past its full length.

Should I insulate my vent hood duct?

You can insulate your vent hood duct, but it’s not required. Insulating your duct will reduce the noise of your blower, if it’s inline with the ductwork. It’ll also help prevent smoke and greasy air from escaping into your joists and attic.

Learn more in this complete article.

Is it possible to change a range hood top duct to a rear duct if it’s a top duct only?

If you have an island range hood, this is not possible. Island range hoods can only vent through the ceiling. But, some wall and under cabinet range hoods have rotatable blowers. This means that you can rotate the blower to vent horizontally or vertically depending on your kitchen setup.

If your ductwork is already installed, it’s not recommended to change your range hood from a top duct to a rear duct. This can be an expensive and time-consuming project that requires a professional contractor.

Can a kitchen operate if half the hood vent system is not running?

It depends on what part of the hood is not running. If the lights are not working, this is often not a huge problem. However, if the motor, touch panel, or circuit board is broken, you will need to call your manufacturer for a replacement. Your hood won’t run efficiently without these parts fully intact.

How to Install a Range Hood Vent Through the Wall

For a complete walkthrough of how to install a range hood vent through the wall, check out this article.

How to Install a Range Hood Vent Through the Ceiling

Check out the full step-by-step on how to install a range hood vent through the ceiling here.

We hope this information on range hood venting options as well as ducted and ductless range hoods has been helpful for you. Thanks for reading!

This article is also intended to help people who are searching for installing ducted kitchen hood vent, kitchen exhaust vent, range hood exhaust vent, oven vent, kitchen vent, rangehood exhaust, rangehood vent, stove vents

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