Roof & Gable Vents
About Roof & Gable Vents
An under-ventilated attic is one of the most common - and most costly - building envelope failures in Canada. Excess heat and moisture accelerate shingle degradation, create ice dams, and cause moisture damage to sheathing and framing that costs tens of thousands to remediate. Yet proper ventilation is also one of the most affordable specifications you can make: a balanced ridge-vent and soffit-vent system costs a fraction of a single moisture callback. Pro Materials supplies a complete roof ventilation system from Kaycan - Ridgemaster® and Hipmaster® ridge vents, gable vents, roof deck vents, soffit vents, mount blocks, and CapMaster® pipe covers - products designed to function together as a balanced system, engineered for Canadian climate conditions from British Columbia to Newfoundland. Wholesale supply to roofing and siding contractors across Canada.
Roof & Gable Vents Buying Guide
Key factors to evaluate when specifying roof & gable vents for your project.
Balanced Roof Ventilation: Getting It Right
The 1:150 ratio
Canada's building code requires a minimum of 1 sq ft of net free ventilation area per 150 sq ft of attic floor space - though many building scientists recommend 1:100 for better performance. Half of that ventilation area should be at the intake (soffits) and half at the exhaust (ridge or gable vents) for balanced airflow. Always calculate the full attic ventilation requirement before specifying products.
Ridge vents vs. gable vents
Ridge venting is the most efficient attic exhaust system because it evacuates the full ridge length and is driven by natural convection and wind. A properly installed ridge vent with baffled soffit vents creates a uniform airflow across the entire attic floor - critical for preventing moisture pockets and hot spots. Gable vents are used where ridge venting is not practical (complex rooflines, hip roofs without ridges) or as supplemental ventilation.
Ridgemaster® selection
Ridgemaster comes in standard and wide-body profiles. The wide-body profile provides greater net free area per linear foot and is preferred on high-pitch roofs and larger homes. Both include an external baffle system that prevents wind-driven rain and snow from entering while allowing unrestricted airflow.
Hip roofs
Kaycan's Hipmaster® is specifically designed for hip-to-ridge transitions on hip roofs, solving the common problem of ventilating the hip ends where standard ridge vents can't terminate properly.
Mount blocks and pipe covers
Every plumbing stack, dryer vent, and utility penetration through the roof needs a properly flashed mount block or pipe cover. CapMaster® covers cap the pipe and integrate with the roofing system to prevent water infiltration. Specify them for every penetration on every project.
Frequently Asked Questions
How do I calculate how much ridge vent I need?
First, calculate your required net free exhaust area: attic floor area ÷ 150 ÷ 2 (since intake handles the other half). For example, a 1,500 sq ft attic needs 5 sq ft of net free exhaust area (= 720 sq in). Ridgemaster® provides approximately 18 sq in of net free area per linear foot. Divide your required square inches by 18 to get the linear footage of ridge vent required. Always verify the specific product's NFA specification on the data sheet.
What is the difference between Ridgemaster® and standard ridge vents?
Ridgemaster® is Kaycan's proprietary ridge vent system with an external external weather baffle and filter mat that prevents wind-driven rain, snow, and insects from entering the attic while providing maximum airflow. Standard contractor-grade ridge vents often lack these features, leading to attic moisture issues from storm-driven precipitation. Ridgemaster also includes a hip-to-ridge transition piece (Hipmaster®) for hip roofs.
Can I mix ridge vents with power ventilators?
Power ventilators and passive ridge vents should generally not be mixed in the same attic space. A power ventilator creates negative pressure in the attic that can reverse airflow through passive ridge vents, drawing unconditioned air and moisture in from the living space rather than exhausting attic air out. If a power ventilator is already installed, it must be sized and controlled to avoid this problem, or removed in favour of a fully passive balanced system.
Do I need both soffit vents and ridge vents?
Yes. A ridge vent without adequate soffit intake (or intake vents in the lower wall) cannot function properly. The ridge vent relies on intake air flowing in at the eaves and exiting at the ridge. Without sufficient intake, the ridge vent draws warm moist air from the living space through light fixtures and ceiling penetrations - which is far worse than no ventilation at all. Balanced intake and exhaust is the foundation of proper attic ventilation.