Haven’t you always wanted to know more about roof ventilation?
OK, so it might not be at the top of your list of things to know. But if you are a homeowner and care about the functionality of your roof, your power bills, and your home maintenance, then you need to keep reading.
Roof ventilation is extremely important for several reasons, and this can be managed by using vents or taking other measures to allow for proper venting of a roof. If you own a home or are thinking about purchasing one then the condition of the roof can be a deal breaker, and replacing a roof can be costly so it is essential that your existing roof was properly installed.
A roof cannot perform at the very best if it is not properly ventilated. Improper installation of venting products or failing to consider ventilation when installing a roof can lead to problems in the future. The cost of replacing a roof can be high, so it is important that every aspect is perfect to avoid this cost before it becomes absolutely necessary due to advanced age.
Why is Roof Ventilation Needed?
Roof ventilation is needed so that the proper amount of air can flow through the roof area. If a home is completely airtight and no airflow is allowed it can cause problems. Moisture cannot evaporate and leave the home. This can cause condensation inside the rooms or on the ceilings. Moisture can lead to fungal growth and damage to the roof materials and drywall.
Shingles that are installed on unvented roof assemblies operate at slightly higher temperatures, roughly 2°F to 3°F warmer than shingles on vented assemblies. This can reduce their service life by roughly 10%
Ventilation can be managed in the roof and attic space by using a system of intake and outtake vents. These allow the air to flow in and out of the home while protecting these areas from moisture getting in at the same time.
Different Ventilation Methods Can be Used
The roof ventilation method and system components used can depend on a number of factors. These may include:
- The typical environment
- The pitch of the roof
- The total size of the roof
- Whether the attic space will be lived in
- The usual high and low temperatures in your area
- The size and configuration of your home
- Your budget
- The roofing contractor who is doing the job
Attic Ventilation Follows These 5 Rules
- Ensure the attic floor is completely sealed. If this is not done then you could experience ice dams and energy loss.
- Place extra insulation above the top plate of the wall before you start on roof ventilation.
- Place vents on the soffit at the farthest outside edge. This will prevent any warm air from flowing into the attic and roof area, melting any snow, and creating ice dams that can cause damage.
- Allow for a minimum of 1 inch of air space between the top of the insulation and the bottom of the roof sheathing. Some professional roofers will insist on at least 2 inches of air space in this area.
- Adding more ventilation at the eaves and less at the ridge of your roof will help to pressurize the attic slightly, and this can prevent energy loss.
Adequate attic ventilation reduces the amount of initial melting that occurs on your roof, thereby reducing the chance that ice dams will form.
Vents and Your Roof Deck
If you plan on using your attic for living space or you have high ceilings then vents may be needed from ridge to eaves on a continuous basis to provide proper roof ventilation. If your roof has any skylights, hips, dormers, or valleys then this can be hard to do or even impossible in some cases. A professional can help you decide which methods will work best.
What are Baffles?
Baffles can be a crucial part of roof ventilation. These are usually foam or another insulation material that is placed in the space at the bottom of the individual rafter bays, and it helps you to create an airtight space. Baffles may be stapled into place and then a foam sealant can be used to eliminate any gaps that allow air into areas you do not want it to go.
Should Baffles be Prefab or Site Built?
When you are considering baffles as part of your roof ventilation system this does not mean that you will not need to include vents, but you will also need to consider whether the baffles will be prefabricated or built on site. Each method will have advantages and drawbacks, and a roofing professional can help you decide.
Click here to learn more about Crane Roofing roof vents.
Is your roof ventilation system appropriate for your home and how do you know?