Ventilation to the Outdoors (IRC M1503. 1): Residential range hoods should vent to the outside to effectively expel smoke, grease, and cooking odors, maintaining the home's air quality.
Wall-mounted & Under-cabinet range hoods – 100 CFM for every linear foot of cooktop. Most common types of cooktops measure 30 inches wide or 2.5'. To meet the recommended CFM requirements, you'll need a range hood with 250 CFM.
A vented range hood, aka a ducted range hood, pulls in air and leads it outside either through the exterior wall or the roof. Going through the exterior wall of your house requires less waterproofing. If you decide to vent through the roof, make sure the vent goes all the way outside and not just into the attic.
Not all range hoods need ventilation, but vented or ducted models do always vent to the outside of a home. This venting can run through an exterior wall, floor or—with the help of a professional—be installed up and out through the roof.
All ducting material from the range hood should be rigid. Flex duct is dangerous and not allowed. It? s not smooth inside and will trap grease inside the ridges and become a potential fire hazard. Flex duct also causes severe air turbulence and will significantly reduce the efficiency of the hood by 50%.
Ventilation to the Outdoors (IRC M1503. 1): Residential range hoods should vent to the outside to effectively expel smoke, grease, and cooking odors, maintaining the home's air quality. This requirement is crucial for preventing the recirculation of contaminants within the home.
A semi-rigid duct offers more durability than a flexible duct. However, the best ducting for your kitchen hood is rigid. It's the most durable option because higher quality materials are used to produce them.
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.
What is a ductless range hood? A ductless range hood is a ventilation system that does not require ductwork to be installed in your home as they filter smoke and odors instead of removing them completely. Because they don't require any ductwork, these range hoods are great for kitchens in a variety of layouts.
Ductless range hoods work just as well as ducted hoods, but they don't need to be vented outside. So, how do they work? It's simple. Using commercial-grade baffle filters, the dirty air is sucked up into the unit and then filtered and returned to your kitchen – without the toxins.
There are range hood firms that suggest that nothing under a 4-inch duct should be used. The 4-size is ideal, which is ideal for range hoods requiring a minimum of 400 CFM. We offer out stainless and aluminum kitchen hood ductwork in sizes up to 12-inch in diameter.
There are no codes enforcing gas stove ventilation, though it is highly encouraged, whether you have a 30-inch gas cooktop, 36-inch gas cooktop, or more. When you use a gas burner on a cooktop there are poisonous gasses emitted. Carbon monoxide poisoning from a gas stove is a very real possibility without a vent.
The Bottom Line
A range hood shouldn't be vented into your attic. There are many ductless options available that will work great if you don't want to add additional ducting to direct kitchen exhaust outdoors. However, if you want a ducted range, there are many ventilation systems to select as well.
Rigid duct is the ideal duct for range hoods. It is the most durable and efficient option. Rigid duct fulfills requirements proposed by the IRC (International Residential Code) for range hood ductwork.
However, ductless models are permitted as an exception to this rule. Kitchens must be vented with a minimum of 25 CFM of continuous air or 100 CFM intermittent air. This is so little CFM that you don't need a range hood to reach this threshold. In fact, residential exhaust fans can reach up to 2000 CFM.
You must 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 to the outside. This way, you'll get rid of the smoke and cooking exhaust for good.
And both are usually connected to a ducting system that removes air from the kitchen and sends it outdoors. The difference is that a vent hood is designed to draw air, while a range hood is designed to push air. A range hood uses a forced-air fan to push air out of the system.
The short answer is no. Not all range hoods need to be vented outside. However, depending on the type of range hood you have, it may be needed. Venting outdoors is the most effective option for removing smoke, steam, and odors from the kitchen.
Most residential building codes do not require a range hood above a stove or cook top, but you'd be wise to ensure your locale is not the exception. Even if it's not legally required, you should think long and hard before forgoing a hood altogether.
There are 2 basic ways to vent a wood-burning stove, (1) straight up and out the ceiling or (2) out the wall and along the side of the house.
If you have an electric cooktop, range hoods should typically be 20–24 inches above the heat source. For gas cooktops, your range hood should be around 24–30 inches above the stove. Range hoods are a great way to complement your cooktop or range and can help clear the air while you cook.
NEVER use a PVC dryer duct or any plastic duct on a range hood installation as is not fire-rated. The minimum size duct allowed on most range hoods is 125mm ranging to 200mm round. More powerful hoods require even larger duct sizes up to 250mm or 300mm round.
For a family of three/four people who cook a variety of dishes, the model should have an airflow capacity equal to 400-500 m3/h. some exotic recipes, the hood capacity should be over 500 m3/h. to low speed and keep the hood on for a further 5-10 min.
Flex ducts are more affordable, ranging from $1 to $4 per linear foot versus $7 to $13 per linear foot for metal. Since they have a simpler installation process, the cost to install or replace flexible ducts is also lower than for rigid ducts.