High Tunnel Greenhouse Vents

High Tunnel Greenhouse Vent with Automatic Opener
Automatic Supplemental Ventilation for Polyethylene High Tunnels

Improve airflow during hot and humid growing conditions with the Ken-Bar 12" High Tunnel Greenhouse Vent with Automatic Opener. Designed for installation directly into polyethylene-covered high tunnels, this end-wall ventilation system provides supplemental airflow when standard ventilation from rolled-up sides and open doors isn't enough.

Installed high on the structure near the roof or peak, the vent takes advantage of the natural chimney effect, allowing rising hot air to escape from the growing area. The automatic temperature-sensitive opener provides convenient ventilation control without requiring constant manual adjustment.

Important: High Tunnel Vents are intended for supplemental ventilation only and are not the primary mechanism for temperature control in high tunnels.

Designed for Polyethylene High Tunnel Installation

The High Tunnel Vent is designed specifically for polyethylene-covered greenhouse and high tunnel structures. Its included lockwire and base channel system allows the vent to be installed directly into the poly covering without requiring additional framing.

This makes it a practical way to add upper-level ventilation to an existing high tunnel while maintaining a clean, streamlined installation.

Automatic Temperature Control

The included temperature-sensitive opener automatically operates the vent based on the surrounding temperature. The opener can be adjusted to open at temperatures between 60°F and 77°F, allowing you to choose the temperature at which supplemental ventilation begins.

The automatic opener can also be quickly detached when manual operation or removal is desired.

Manual Operation

In addition to automatic temperature control, the vent can be operated manually using a simple pull-cable mechanism. This gives growers the flexibility to control ventilation directly when desired.

Durable, Lightweight Aluminum Construction

The High Tunnel Vent features a rigid, lightweight aluminum frame and shutter designed for greenhouse ventilation applications. Its durable construction provides a practical solution for adding supplemental airflow to polyethylene-covered growing structures.

Positioning the vent near the roof or peak allows rising warm air to exit the tunnel, complementing conventional ventilation through rolled-up sides and open end doors.

High Tunnel Vent Specifications
Construction: Rigid, lightweight aluminum frame and shutter
Installation: Directly into polyethylene high tunnel covering
Installation system: Lockwire and base channel included
Automatic opener: Included
Automatic temperature range: Adjustable from 60°F–77°F
Manual operation: Pull cable
Application: Supplemental high tunnel and greenhouse ventilation
Ideal for Hot & Humid Growing Conditions

During moderate weather, high tunnels are typically ventilated by rolling up the sides and opening doors at each end. During periods of extreme heat and humidity, however, additional upper-level ventilation can help move hot air out of the structure.

Because warm air naturally rises, a high-mounted vent provides an effective escape point for accumulated heat. The Ken-Bar High Tunnel Vent can complement your existing ventilation strategy by adding airflow at the upper portion of the tunnel.

Ideal applications include:

Polyethylene-covered high tunnels
Vegetable-growing tunnels
Small and medium greenhouse structures
End-wall ventilation
Upper-level greenhouse ventilation
Nursery growing structures
Hobby and production greenhouses
Supplemental hot-weather ventilation
Multiple Sizes Available

Ken-Bar High Tunnel Vents are available in multiple sizes to accommodate different ventilation requirements:

Vent Size Shutter Opening Approx. Assembled Dimensions
12" × 12" 12.5" × 12.5" 15" × 15" × 3" closed – 6" open
16" × 16" 16.5" × 16.5" 19" × 19" × 3" closed – 6" open
18" × 18" 18.5" × 18.5" 21" × 21" × 3" closed – 6" open
20" × 20" 20.5" × 20.5" 23" × 23" × 3" closed – 6" open
24" × 24" 24.5" × 24.5" 27" × 27" × 3" closed – 6" open
30" × 30" 30.5" × 30.5" 33" × 33" × 3" closed – 6" open
Need a Framed-Installation Model?

The model featured here is designed for direct installation into polyethylene film structures.

For rigid structures, framed installations, or polycarbonate glazing, choose a Ken-Bar High Tunnel Vent designed specifically for framed installation.

Add Automatic Upper-Level Ventilation

The Ken-Bar High Tunnel Greenhouse Vent makes it easy to add supplemental ventilation to a polyethylene-covered high tunnel. With its lightweight aluminum construction, direct-to-poly installation system, adjustable 60°F–77°F automatic opener, and manual pull-cable option, it provides flexible ventilation when growing conditions become excessively hot and humid.