Vents - Clam Shell, Cabin, Louvered, Hose, Cowl

Clam Shell Vents, Cabin Vents, Louvered Vents, Hose Vents, and Cowl Vents - Resources & Information

Ventilation is absolutely essential for the safety and comfort of your boat. The purpose of vents is to allowing air to pass through while keeping out unwanted elements, such as splashing water and condensation, or for providing passage for wires, cables, and blower-exhaust hose openings.

PartsVu offers a complete selection of Marine Wrenches from OEM manufacturers and trusted aftermarket suppliers. Whether you need an boat hull vents, marine cowl vent, boat side vents, and more, PartsVu has what you need to get the job done. 

Need help servicing your boat and outboard engine? PartsVu regularly publishes helpful how-to guides and other valuable maintenance information to help boaters properly service their boats and engines. Browse our outboard maintenance blog for a wide range of relevant topics and see the FAQ section below, covering everything you need to know about maintaining your boat in confidence.

Marine Vents FAQ

What should I know about Clam Shell Vents, Cabin Vents, Louvered Vents, Hose Vents, and Cowl Vents?

Here’s some info you need to know about Clam Shell Vents, Cabin Vents, Louvered Vents, Hose Vents, and Cowl Vents:

• A louvered vent is a type of ventilation system commonly used on boats to allow air to flow into and out of the boat's interior. Boat vents are typically located near the top of the hull, and consist of a series of angled slats that can be opened and closed to control the flow of air. This type of vent is designed to provide effective ventilation while also helping to keep out water and other elements.
• A marine clam shell vent is a type of ventilation system commonly used on boats. It consists of two semi-circular pieces of equipment that open and close like a clam shell to allow air to flow in and out of the boat's interior. The clamshell vent is typically located near the top of the boat's hull, and is designed to provide effective ventilation while also helping to keep out water and other elements.
• A hose vent could refer to any type of ventilation system that uses a hose to allow air to flow in and out of a space. This could include a ventilation system for a boat, a building, or any other type of enclosed space. Hose vents are often used in situations where it is necessary to provide ventilation while also preventing water or other elements from entering the space.
• A cowl vent is a type of ventilation system that is commonly used on boats. It consists of a circular or oval-shaped vent that is mounted near the top of the boat's hull. The cowl vent is designed to allow air to flow into and out of the boat's interior, while also helping to keep out water and other elements. The cowl vent is typically mounted on a pivot, so that it can be opened and closed to control the flow of air. In some cases, the cowl vent may also be equipped with a fan or other mechanism to help force air into or out of the boat's interior.
• A cabin vent is a type of ventilation system that is commonly used on boats. It is typically located near the top of the boat's cabin, and is designed to allow air to flow into and out of the boat's interior. The cabin vent is typically made of durable materials, such as metal or plastic, and is designed to withstand the harsh marine environment. It is often equipped with a mechanism, such as a pivot or a hinge, that allows the vent to be opened and closed to control the flow of air. In some cases, the cabin vent may also be equipped with a fan or other mechanism to help force air into or out of the boat's interior.

Are plastic vents or metal marine vents better for boats?

In general, most marine vents are made from non-corroding metals like aluminum, chrome, and stainless steel. Because of the inherent properties of these metals, they can stand up to corrosion from salt water, moisture in the marine environment, and continual wear and tear. Plus, these metals tend to add visual appeal that adds value to your boat.

Plastic vents are usually a good option for interior applications in the cabin or as side vents; however, caution should be used for plastic vents in areas and applications that experience high temperatures due to prolonged exposure to sunlight (ie. deck mount vents) or exhaust louvers and vents for inboard/sterndrive motors. Also, due to the nature of plastic, plastic vents will begin to degrade and crack over time much quicker than metal.

Why should boaters install an inboard gasoline boat ventilation system

Installing a ventilation system on your inboard gasoline boat is important for several reasons. First, it helps to prevent the build-up of dangerous gases, such as carbon monoxide, inside the boat's interior. These gases can be harmful to your health, and can even be deadly in high concentrations. A ventilation system helps to keep the air inside the boat fresh and safe to breathe.

Second, a ventilation system can help to prevent the build-up of moisture inside the boat, which can cause damage to the boat's interior and its equipment. Moisture can lead to the growth of mold and mildew, which can cause health problems and can damage the boat's structure and equipment. A ventilation system helps to keep the air inside the boat dry and prevent moisture build-up.

Third, a ventilation system can help to regulate the temperature inside the boat, making it more comfortable for you and your passengers. A well-ventilated boat will stay cooler in the summer and warmer in the winter, providing a more pleasant environment for you and your passengers.

Overall, installing a ventilation system on your inboard gasoline boat is an important safety measure that can help to protect your health and the condition of your boat.

What are the different types of boat ventilation? 

Maintenance Ventilation

In most climates, boats that have been closed for a period of time will become “stuffy.” The temperature differential that develops between the boat cabin and the outdoor environment will cause the humidity level inside the boat cabin to rise. When the humidity level in the closed cabin rises, moisture forms, resulting in mold, mildew and musty air. In these conditions, fabrics, boat electronics and even the boat’s fiberglass structure can be damaged. By consistently replacing trapped, stale air in the closed boat with fresh outside air, the humidity equalizes from inside to outside, resulting in effective maintenance ventilation.

Comfort Ventilation

Combining different types of vents, with one vent providing “intake” air flow while another vent providing “exhaust” air flow, creates cross flow ventilation. A cross-flow ventilation system will make the interior cabin more comfortable and pleasurable because air is constantly moving throughout the cabin. No matter what your boat size or cabin configuration is, you can increase your boating enjoyment with the addition of ventilation.

Safety Ventilation

Most boaters are unaware of the hazards that exist in the boating environment. Any number of serious ventilation problems can occur when a boat is left unattended. And even if you are underway, these problems don’t go away. Fumes and gasses, ranging from carbon monoxide to hydrogen gas from battery charging, to gasoline, propane or solvents stored below, are unpleasant, and can sometimes be dangerous. Also, any open flame devices in the cabin require proper ventilation. Ventilation helps to eliminate these hazards by providing constant air circulation resulting in effective safety ventilation.

How much ventilation is required for your boat?

Ideally, the air in the interior of a boat should be circulated once every hour. A typical 30-foot boat contains approximately 800 cubic feet of air. The general guidelines for providing maintenance ventilation are as follows:

Boat Size Recommended Ventilation

• Up to 24'. 1 Exhaust Vent*
• 24' to 40'. 1 Exhaust Vent & 1 Intake Vent
• 40'. and larger 2 Exhaust Vents & 1 Intake Vent

* For effective maintenance ventilation, one vent assumes there will be access for air to get into the cabin (i.e., cowl vent, clamshell vent or louvered panel)

It is important to evaluate the cabin layout of your boat to determine optimal locations for both intake and exhaust ventilation.