Everything to Know About Roof Vent Caps

By Cynthia Pigeon

Updated on November 7, 2023

While thermal insulation is a top priority for most homeowners, proper roof ventilation is also critical to keeping your roofing system in tip-top shape. A roof vent cap is key to achieving this goal.

In this article, we'll delve into the essential information one must know concerning these vent caps, including the importance of their function, the different models available, features, and more. If you want to know which cap is best suited to your needs, keep perusing this article so you don't miss anything.

Why Add a Roof Vent Cap?

Blog image

Source : Canva

Roof vent caps are easy to install and provide optimum air circulation. As a result, your roof is always kept dry during the colder winter months and cool during hot summer days.

A vent cap is perfect to release exhaust air from kitchen range hoods, bathroom fans, and clothes dryers. The damper mechanism opens to allow exhaust air to flow out and then closes automatically. This airtight barrier will also help you reduce your energy bills.

The damper usually has a deflector combined with a unique design. These two elements prevent it from flapping and also funnels rainfall sideways. This mechanism also prevents insects and rodents from gaining access to your attic, unlike some roof vents.

As such, if you want to keep clean air in and moisture out, reduce your energy consumption, and have a long-lasting roof, we highly suggest installing a roof vent cap.

Roof Vent Cap Models & Features

Blog image

Source : Canva

The roof vent cap you choose to install will have a significant impact on the overall ventilation and efficiency of your roofing system. To help you narrow down which model will best suit your needs, we thought it would be a good idea to highlight some of the most popular vent caps:

VMAX-CT-6 Roof Exhaust Vent Cap

The VMAX-CT-6 vent cap is considered by roofing professionals in Quebec as one of the best air exhaust solutions you can possibly install on your roof. It can be mounted on bathroom fans, dryers, kitchen range hoods, air exchangers, etc.

Its unique design prevents the cap from flapping and any air backflow; the air discharged is directed upwards to prevent odours from permeating the roof’s surface and to provide a better air distribution within the environment.

Features:

  • 6 inches in diameter;

  • 7 ¾ inches high and 7 ¼ inches wide;

  • Can be installed on a roof pitch between 2/12 to 15/12;

  • Made with structural-grade galvanized steel (can be custom-made with aluminum);

  • Anti-gust system resistant to infiltration;

  • Built-in galvanized security screen mesh;

  • Cured polyester powder paint that protects against UV rays and corrosion (5-year warranty);

  • Options: black, grey, brown, and limited special paint colour options for an additional fee;

  • Limited lifetime warranty against manufacturing defects.

Vmax-CT-10 Roof Exhaust Cap

Like the above-mentioned roof vent cap, this model's also favoured by roofing professionals.It also offers the same advantages.

In addition, the Vmax-CT-10 roof exhaust cap is distinguished by these features:

  • A 10-inch (in diametre) round pipe;

  • 3 ¼ inch X 10-inch rectangular exhaust pipes;

  • A height of 7 ¾ inches and a width of 11 ¼ inches; 

  • Can be installed on a roof with a pitch that varies between 2/12 and 15/12.

Gooseneck Exhaust Vent With or Without Collar

large vent cap

Source: Henry & Co. - Unsplash

This roof exhaust vent model is ideal to pull air from bathroom fans and dryers. It can be mounted on a sloped, shingled rooftop. Due to its deflector and exterior grill, it effectively reduces backdrafts, and prevents infiltrations, birds’ nests, and anything else that could be detrimental to its function (rodents, insects, etc.). 

Its basic features and advantages are listed below:

  • Seamless and leak-free;

  • Ideal for 4-, 5-, or 6-inch ducts;

  • Resistant to impacts and below 40°C weather;

  • CSA approved;

  • Features a 35-year warranty;

  • Made of UV- and corrosion-resistant polypropylene.

Are you looking for experts to tackle your roofing project?

Fill out our form to receive quotes from certified contractors!

VMAX-CT-4 Roof Exhaust Vent Cap

Like the CT-10 roof exhaust vent cap, this one, the CT-4, is made of galvanized steel and allows for good air circulation, protecting your roof from strong gusts of wind, rodents, UV rays, corrosion, and much more. It can be installed on bathroom fans, dryers, air exchangers, and any other exit. 

Basic features:

  • 4-inch in diameter; 

  • 7 ¾ inches high and 5 ¼ inches wide;

  • Can be installed on roofs with a pitch between 2/12 and 15/12;

  • Anti-gust and anti-infiltration system;

  • Standard colours (black, grey, brown);

  • Same features as the VMAX-CT-6 exhaust vent cap.

VMAX-CT-AD-12 Roof Exhaust Vent Cap 

This cap was developed to provide, given its size, better manoeuvring when installing the ducts, especially in restricted spaces. As such, its height also allows it to easily resist adverse weather conditions and snow build-up, and spares it from being entirely covered. Also, its unique concept allows for the exact net of airflow to enter and exit your roof’s system without restrictions, thus eliminating backflow pressure. Here are this cap's characteristics:

  • Best suited for ducts that are between 3 and 6 inches in diameter;

  • Can be installed on flat and sloped roofs;

  • The insulated damper mechanism significantly reduces noise levels;

  • As for the rest, it has the same basic functions as the previously-mentioned vent caps.

VMAX-CTM Roof Exhaust Vent Cap

greenhouse roof vent cap

Source: Jason Shivers - Pixabay

With this model of vent cap, you can combine multiple mechanical exhaust units within the same connection, which limits the number of holes in your roofing. Much like the VMAX-CT-AD-12 vent cap, this model allows for an exact net of airflow to enter and exit, which prevents backflow pressure. Also, it was designed to reduce noise levels, and its characteristics are very much the same as the previously-mentioned models. 

The price of a roof exhaust vent cap varies based on several factors, most notably the cap itself, based on its manufacturing material, type of finish, and its dimensions. Expect to pay anywhere from $50 to $150 per unit. 

Cover photo source: Blake Wheeler - Unsplash

Get 3 quotes for your roofing project

RenoQuotes.com will put you in contact with 3 reliable contractors for your roofing renovation project. Fill in the form on our homepage (it only takes a few minutes), and you will receive quotes from trusted professionals.

Dial 1-844 828-1588 to speak with one of our customer service representatives.


Get 3 free quotes for your project!

Submit a project and get 3 free quotes!

Looking for something else?

Table of contents

4 min read

Find contractors near you

Enter your postal code



Related articles

The latest industry news, interviews, technologies, and resources.

5 min read

Editorial Team

23 Jan 2025

Essentials of Calgary Roofing: A Homeowner's Guide to Roof Maintenance and Repair

Protecting your home starts at the top, and understanding your roof is essential to this task. The unique weather patterns in certain regions pose specific challenges for homeowners. Proper knowledge of these challenges can help in making informed decisions about your roof.

Roof
6 min read

Editorial Team

03 Nov 2025

Lifespan of A Roof

Having a roof over your head is a common luxury that many homeowners may take for granted. Your roof spends its lifetime outside, coming up against all the rain, wind, sun and snow that the weather throws its way. For this reason, it is fairly likely that your roof will experience wear and tear, leading to the potential for cracks, breaks and leaks.

Roof
13 min read

Editorial Team

08 Dec 2025

Foundation Repair Project Cost: How Much to Budget in 2025?

Foundation repairs are crucial for structural maintenance. The overall cost of foundation work depends on excavation depth, soil type, and building size, and may rise significantly in 2025 based on damage severity. This article outlines solutions to help you budget effectively.

Price guide
6 min read

Christine Simard

07 Nov 2023

September 2020: 10 Home Decor and Renovation Articles to Check Out

As the month of pre-Halloween (September) comes to an end, giving way to the beautiful month of "spooky season" (October), it’s time to start getting cozy and digging out your warmer clothes as the temperature drops and leaves fall off trees. Autumn celebrations aside, it’s also time for our monthly roundup of the best design, decor and renovation articles found on the internet!

4 min read

Christine Simard

07 Nov 2023

Biophilic design: a starting guide

Over the past two years, we have often mentioned the phenomenon that is biophilic design but never really delved into the depths of this trend. With people growing more and more conscious of the need for a more sustainable future, the architecture and design world soon picked up on those issues and are now working around the inclusion of these principles in their practices.

Design and home decor