There are traditionally four main reasons for venting a roof.
Vent vs unvented roof.
These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck.
Control of ice dams moisture accumulation and heat gain can be successfully addressed by both vented and unvented attic or roof design.
Vented vs unvented attic.
Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction.
The majority of roofing experts agree that ridge vents are the most effective and cost effective roof vents available.
Moisture content in roof structure must be less than 18 prior to covering.
Unvented roofs which provides a detailed explanation of each.
In this case you can learn a lot from foam tech s article vented vs.
Unvented roofs vented roof.
While hardly anybody agrees on the best roof ventilation system everybody agrees some roof vents do hardly any good at all.
A secondary goal is to vent moisture that infiltrates the attic from the conditioned home.
In colder climates the main purpose of a vented roof is to keep the roof cold and reduce the formation of ice dams.
However the designs need to be climate sensitive.
When insulating your attic the contractor can either spray the attic floor to keep a vented attic or spray the roof deck for an unvented system.
Removing moisture from roof cavities structural members sheathing and insulation.
Vented roofs serve a number of different purposes and their roles vary from climate to climate.
Both vented and unvented attic roof designs can be used in all hygro thermal regions.
Controlling ice damming by keeping the roof cold.
Basically the term cold roof refers to a traditional roof or vented roof while hot roof refers to a roof that is not ventilated and which has foam insulation attached directly to the roof sheathing.
There are important layers between the soffit and your attic.
Learn the difference between vented soffit and non vented soffit.
I have roof vents so i have roof ventilation.
The choice of the venting approach is up to the designer.
Enhancing roofing material life span by reducing sheathing temperature.
Because the drying capacity of unvented roof assemblies is inherently lower than vented ones it is especially critical to control built in moisture during construction.
You re here to figure out which attic system is best for your home but it s also important to understand how each system works.
