Vent Cooking Odors Outside with a Wall-Mounted Exhaust Fan

If your kitchen lacks the ceiling height or roof access for a traditional overhead exhaust fan, installing a through-the-wall model can be a convenient alternative. Wall-mounted kitchen exhaust fans are designed to ventilate cooking fumes, smoke, grease, and odors directly to the outdoors through a duct in the wall.

Compared to roof or ceiling fans, wall-mounted fans take up less space, require shorter ductwork, and are often simpler to install as a DIY project. They also operate more quietly and can match the decor of your kitchen with customizable finishes.

How Do Through-the-Wall Exhaust Fans Work?

Through-the-wall kitchen exhaust fans function similarly to traditional overhead fans but are mounted horizontally in an exterior wall rather than vertically to the ceiling or roof. An interior cover plate fits against the interior wall while a housing sleeve passes through to the exterior side.

The fan pulls cooking exhaust through filters or a grease trap and pushes it outside through ductwork terminating in a weatherproof hood or cap. The motor and impeller blades can be mounted inside the duct or in the exterior housing.

Fan Types and Configurations

The most common types of fans used in wall-mounted kitchen exhaust fans are centrifugal blowers or axial fans. Centrifugal blowers use a spinning impeller wheel inside a cylindrical housing to draw air in parallel to the motor and expel it outward perpendicular through an exhaust vent.

Axial fans pull air directly through the fan along the axis of the motor. They can move high volumes but are less effective for kitchen ventilation since they don't build much pressure. Direct drive motors mount the fan blades directly to the motor shaft. Belt drive motors use a belt and pulleys to turn the fan.

Some wall exhaust units have a single blower while heavy duty commercial models may have a dual blower. Multiple fans can increase airflow capacity and redundancy.

Benefits of Through-the-Wall Kitchen Exhaust Fans

Installing a kitchen exhaust fan through the wall offers several advantages over ceiling or roof fans:

• Don't require attic or roof access - Easier to install in buildings without venting pathways above the kitchen.
• Quieter operation - Shorter duct runs and insulated housings reduce noise.
• Energy efficient models - DC motors and improved designs reduce power consumption.
• Easier DIY installation - Wall mounts are simpler for non-professionals than working overhead.
• Shorter ducting - Venting through the wall often requires a shorter duct pathway.

Wall-mounted fans also take up less interior space and can include features like timers, sensors, and remote controls. Installation does not require major structural modifications which makes retrofitting existing kitchens simpler.

Key Factors When Selecting a Wall Exhaust Fan

Choosing the right through-the-wall exhaust fan for your kitchen depends on several key factors:

Airflow (CFM) Capacity

One of the most important specifications of a kitchen exhaust fan is the airflow capacity measured in cubic feet per minute (CFM). The CFM rating indicates the volume of air the fan can exhaust.

Select a fan with adequate CFM for the size of your kitchen. Larger kitchens with bigger appliances like commercial ranges require more airflow. For example, a 10x10 ft home kitchen may only need a 300 CFM fan while a restaurant kitchen would need 1000 CFM or more.

Noise Rating (sones)

Excessive fan noise can make the kitchen uncomfortable, especially in open floor plan homes where the kitchen is adjacent to living areas. Look for quieter fans with lower sone ratings if noise is a concern.

Factors that reduce noise include insulation around the motor, larger ducts, rubber mounts and gaskets, and designs that allow buffered air intake. Selecting a fan that vents outside rather than into an attic space also lowers kitchen noise.

Ducting

Check the ducting size recommended or required by the exhaust fan model. 6-inch round ducting is common for household kitchens while commercial fans may need 10-inch or rectangular ducts capable of higher airflow.

Consider how the ducting will be routed from the fan to the outside termination. Shorter, straight duct runs are optimal. Avoid 90-degree turns when possible and use sweeping elbows if needed. The ducting must be air-tight and well insulated.

Additional Features

Many wall-mounted kitchen exhaust fans come with bonus features that add convenience and customization:

• Timers - Automatically turn on/off the fan at set times.
• Sensors - Sense heating activity and turn fan on automatically.
• Remote controls - Adjust fan from anywhere in the kitchen.
• Automatic shut-off - Turn off if overheating detected.
• Grease filters - Trap cooking grease from exhaust air.
• Fire suppression - Integrated wet chemical system.
• Filters - Charcoal for odor control or aluminum mesh.

Consider which extra capabilities would be useful in your kitchen environment or cooking style when selecting a model.

Installation Considerations

Properly installing a through-the-wall kitchen exhaust fan requires planning the ducting path, wiring electrical connections, weatherproofing, and securing the housing in the wall opening:

Electrical Requirements

The fan will require a grounded electrical connection with ample amperage and correct voltage. This usually requires running wiring through the wall cavity from the switch location to the fan housing. Hire an electrician if you are not experienced with household electrical projects.

Wall Sleeve Sizing

Measure the housing dimensions of the exhaust fan and cut a matching opening in the wall. Install a wall sleeve the same size as the fan housing so it can slide in securely. Seal any gaps in the sleeve with caulk.

Ducting and Connections

Run rigid ducting from the fan housing to a weatherproof termination outside. Use metal duct tape and mastic to seal all joints and connections. Avoid excessive turns or kinks that could restrict airflow.

Weather Sealing

Seal any openings around the housing and ducting with weather stripping, caulk, mastic, or expanding foam to prevent air leaks, moisture intrusion, or pest access.

Permits and Codes

Check your local building codes to determine if permits or licensed contractors are required. HVAC technicians usually have the skills needed for kitchen exhaust fan installation.

Replacing an Existing Wall Fan

When replacing an existing through-the-wall exhaust fan, the key steps are:

1. Turn off power and disconnect the fan electrically.
2. Remove the existing fan unit from the wall sleeve or housing.
3. Inspect the opening size and existing ductwork path.
4. Purchase a replacement fan with equal or greater CFM and same housing dimensions.
5. Install the new fan in the existing wall sleeve after wiring it.
6. Be sure to seal any gaps around the new housing.

Upgrading the electrical wiring or increasing the ducting size may also be necessary depending on the requirements of the new fan.

Maintenance Tips

Regular maintenance is important for any kitchen exhaust fan to keep it operating properly for years:

• Clean filters - Grease and charcoal filters should be cleaned monthly.
• Inspect ducts - Ensure ducting is intact and not leaking.
• Test backdraft damper - Confirm the damper is moving freely to close when the fan shuts off.
• Check/replace belts - Belt driven fans may need new belts over time.
• Lubricate - Apply machine oil to any grease fittings per manufacturer.

A well maintained fan prevents grease buildup and keeps kitchen air flowing smoothly 24/7.

Top Brands and Recommended Models

Leading brands of commercial and residential through-the-wall kitchen exhaust fans include:

• Greenheck - Reliable heavy duty restaurant kitchen fans.
• Loren Cook - Efficient inline and utility fans.
• PennBarry - Comprehensive ventilation solutions.
• Broan - Residential kitchen and bath fans.
• Fantech - Kitchen, laundry, and HVAC fans.

For a small to medium home kitchen, the Broan 509M Through Wall Exhaust Fan is an excellent choice. It offers 680 CFM airflow capacity in a compact 7-inch housing. The 4-speed motor allows variable output from 160 - 680 CFM. At just 0.8 sones, it operates quietly for its power.

For commercial kitchens, the Loren Cook CSF Series is a solid industrial wall exhaust fan, available from 750 - 15,000 CFM. The direct drive motor, corrosion resistant coating, and baked powder finish ensure durability in restaurant environments.

Costs of Wall Exhaust Fan Installation

The total cost to install a new through-the-wall kitchen exhaust fan averages $800-$1200. This includes:

• Fan unit - $100 - $800 depending on CFM, features, commercial vs. residential.
• Ducting parts - $50 - $100 for connectors, damper, cap, clamps.
• Electrical components - $50 - $150 for wiring, outdoor outlet, etc.
• Labor - $300 - $800 if hiring an HVAC or electrical contractor.

DIY installations can save significantly on labor costs but require carpentry and electrical skills. Always get permits if required by local codes.

Through-the-wall exhaust fans offer a versatile solution for kitchen ventilation in spaces where roof and ceiling access is limited. They are simpler to install than traditional overhead fans and operate quietly and efficiently.

Choosing a size appropriate for your cooking equipment, considering noise ratings, planning safe ducting, and proper installation are key to getting the most performance from your new wall-mounted exhaust fan. With some regular maintenance, these fans will keep your kitchen free of odors, smoke, and humidity for years.